Dao \u0111\u1ed9ng ngu\u1ed3n: Kh\u00e1i ni\u1ec7m, c\u00e1ch \u0111o l\u01b0\u1eddng v\u00e0 khi n\u00e0o n\u00f3 quan tr\u1ecdng<\/title>\n<\/head>\n<body>\n\n<div class=\"bd-post\">\n <style>\n \/* fonts: BLOG scope only (brand Standard Blog CSS Header, verbatim). *\/\n @import url('https:\/\/fonts.googleapis.com\/css2?family=Manrope:wght@400;600;700&family=Roboto:wght@600;700&display=swap');\n\n .bd-post {\n \/* brand header system values + plan palette (single source of hex) *\/\n --prose-width: 760px;\n --gap-attach: 16px;\n --gap-normal: 32px;\n --gap-section: 48px;\n --pad-compact: 16px;\n --pad-standard: 24px;\n --body-bg: #FFFFFF;\n --text-primary: #333333;\n --text-secondary: #6E6E6E;\n --heading-ink: #000000;\n --accent: #479DE2;\n --accent-text: #2A76B4;\n --accent-on-tint: #1F5F9E;\n --accent-hover: #1F4E8C;\n --accent-hot: #FD9649;\n --inverse-bg: #1E1E1E;\n --inverse-text: #FFFFFF;\n --inverse-text-2: #B8B8B8;\n --card-fill: #E3F0FB;\n --card-border: #3F76AE;\n --card-secondary: #5F5F5F;\n --btn-white: #FFFFFF;\n --btn-ink: #0D3972;\n font-family: \"Manrope\", sans-serif;\n font-size: 16px;\n font-weight: 400;\n line-height: 1.6;\n color: var(--text-primary);\n background: var(--body-bg);\n padding: 40px;\n max-width: 100%;\n box-sizing: border-box;\n }\n .bd-post a { overflow-wrap: anywhere; word-break: break-word; }\n .bd-post p, .bd-post li { overflow-wrap: break-word; }\n .bd-post .bd-post-article { max-width: var(--prose-width); margin: 0 auto; }\n\n \/* anchor permit-list: visual props only on the four content forms *\/\n .bd-post p a, .bd-post li a, .bd-post blockquote a, .bd-post td a {\n color: var(--accent-text);\n text-decoration: underline;\n text-underline-offset: 2px;\n }\n .bd-post p a:hover, .bd-post li a:hover, .bd-post td a:hover { color: var(--accent-hover); }\n\n \/* PROSE SPACING \u2014 fixed standard, brand header heading values *\/\n .bd-post h1 { font-family: \"Roboto\", sans-serif; font-weight: 600; font-size: 34px; line-height: 1.2; color: var(--heading-ink); margin: 0 0 16px; }\n .bd-post h2 { font-family: \"Roboto\", sans-serif; font-weight: 700; font-size: 34px; line-height: 1.2; color: var(--heading-ink); margin: 48px 0 16px; }\n .bd-post h3 { font-family: \"Roboto\", sans-serif; font-weight: 700; font-size: 24px; line-height: 1.25; color: var(--heading-ink); margin: 32px 0 12px; }\n .bd-post p { margin-top: 0; margin-bottom: 1em; }\n .bd-post ul, .bd-post ol { margin: 0 0 1em; padding-left: 1.5em; }\n .bd-post li { margin-bottom: 0.5em; }\n .bd-post ul li::marker, .bd-post ol li::marker { color: var(--accent-text); }\n .bd-post strong { font-weight: 700; color: var(--heading-ink); }\n\n \/* selector hygiene: box-model only via specific classes *\/\n .bd-post [class*=\"bp-\"], .bd-post [class*=\"rich-\"] { box-sizing: border-box; }\n .bd-post .bd-post-article > .rich-checklist,\n .bd-post .bd-post-article > .rich-callout,\n .bd-post .bd-post-article > .rich-steps,\n .bd-post .bd-post-article > .bp-takeaway-card { margin: var(--gap-normal) 0; }\n .bd-post .bd-post-article > .bp-specnote-card { margin: var(--gap-section) 0; }\n .bd-post .bd-post-article > .bp-cta-end { margin: var(--gap-section) 0; }\n\n \/* ===== Rich elements (content-side authored visual blocks) ===== *\/\n .bd-post .table-wrapper { overflow-x: auto; margin: var(--gap-normal) 0; }\n .bd-post table { width: 100%; border-collapse: collapse; font-size: 15px; }\n .bd-post th {\n background: var(--card-fill); color: var(--heading-ink); font-weight: 700;\n text-align: left; padding: 12px 16px;\n border: 1px solid var(--card-border); border-bottom: 2px solid var(--card-border);\n }\n .bd-post td { padding: 12px 16px; border: 1px solid var(--card-border); color: var(--text-primary); vertical-align: top; }\n .bd-post .rich-matrix tbody td:first-child { font-weight: 700; }\n .bd-post .rich-matrix { border: 1px solid var(--card-border); }\n\n .bd-post .rich-checklist { background: var(--card-fill); border: 1px solid var(--card-border); border-radius: 8px; padding: var(--pad-standard); }\n .bd-post .rich-checklist-title, .bd-post .rich-steps-title, .bd-post .bp-takeaway-title {\n font-weight: 700; font-size: 17px; color: var(--heading-ink); margin: 0 0 12px;\n }\n .bd-post .rich-icon { display: inline-flex; vertical-align: -0.2em; margin-right: 8px; color: var(--accent-on-tint); }\n .bd-post .rich-icon svg, .bd-post .rich-item-icon svg { width: 18px; height: 18px; }\n .bd-post .rich-checklist-list { list-style: none; padding-left: 0; margin: 0; }\n .bd-post .rich-checklist-list li { display: flex; align-items: flex-start; gap: 10px; margin-bottom: 10px; }\n .bd-post .rich-checklist-list li:last-child { margin-bottom: 0; }\n .bd-post .rich-item-icon { display: inline-flex; color: var(--accent-on-tint); flex: 0 0 auto; margin-top: 2px; }\n\n .bd-post .rich-callout { background: var(--card-fill); border: 1px solid var(--card-border); border-left: 4px solid var(--card-border); border-radius: 8px; padding: var(--pad-standard); display: flex; align-items: flex-start; gap: 14px; }\n .bd-post .rich-callout-icon { display: inline-flex; color: var(--accent-text); flex: 0 0 auto; }\n .bd-post .rich-callout-icon svg { width: 22px; height: 22px; }\n .bd-post .rich-callout p { margin: 0; }\n\n .bd-post .rich-steps { background: var(--card-fill); border: 1px solid var(--card-border); border-radius: 8px; padding: var(--pad-standard); }\n .bd-post .rich-steps-list { list-style: none; padding-left: 0; margin: 0; counter-reset: bdstep; }\n .bd-post .rich-steps-list li { display: flex; align-items: flex-start; gap: 12px; margin-bottom: 10px; }\n .bd-post .rich-steps-list li:last-child { margin-bottom: 0; }\n .bd-post .rich-step-num {\n flex: 0 0 auto; width: 24px; height: 24px; border-radius: 50%;\n background: var(--inverse-bg); color: var(--inverse-text);\n font-weight: 700; font-size: 13px;\n display: inline-flex; align-items: center; justify-content: center; margin-top: 1px;\n }\n\n \/* ===== BP-specnote (\u7ad94, plan) ===== *\/\n .bd-post .bp-specnote-card { background: var(--card-fill); border: 1px solid var(--card-border); border-radius: 8px; padding: var(--pad-standard); margin: var(--gap-section) 0; }\n .bd-post .bp-specnote-cells { display: flex; gap: 24px; }\n .bd-post .bp-specnote-cell { flex: 1; min-width: 0; }\n .bd-post .bp-specnote-cell + .bp-specnote-cell { border-left: 1px solid var(--card-border); padding-left: 24px; }\n .bd-post .bp-specnote-label { font-weight: 700; font-size: 15px; color: var(--accent-on-tint); margin: 0 0 4px; }\n .bd-post .bp-specnote-text { font-size: 15px; color: var(--text-primary); margin: 0; }\n .bd-post .bp-specnote-foot { font-size: 14px; color: var(--card-secondary); margin: 16px 0 0; }\n\n \/* ===== BP-takeaway (\u7ad96, plan) ===== *\/\n .bd-post .bp-takeaway-card { background: var(--card-fill); border: 2px solid var(--card-border); border-radius: 8px; padding: var(--pad-standard); }\n .bd-post .bp-takeaway-title { display: flex; align-items: center; gap: 8px; }\n .bd-post .bp-takeaway-title .bp-takeaway-icon { display: inline-flex; color: var(--accent-on-tint); }\n .bd-post .bp-takeaway-title .bp-takeaway-icon svg { width: 20px; height: 20px; }\n .bd-post .bp-takeaway-title span { margin-right: 0; }\n .bd-post .bp-takeaway-rows { display: flex; flex-direction: column; }\n .bd-post .bp-takeaway-row { display: flex; align-items: flex-start; gap: 12px; padding: 12px 0; border-top: 1px solid var(--card-border); }\n .bd-post .bp-takeaway-row:first-child { border-top: none; padding-top: 0; }\n .bd-post .bp-takeaway-row:last-child { padding-bottom: 0; }\n .bd-post .bp-takeaway-num {\n flex: 0 0 auto; width: 28px; height: 28px; border-radius: 50%;\n background: var(--inverse-bg); color: var(--inverse-text);\n font-weight: 700; font-size: 14px;\n display: inline-flex; align-items: center; justify-content: center; margin-top: 1px;\n }\n .bd-post .bp-takeaway-text { font-size: 15px; color: var(--text-primary); margin: 0; }\n\n \/* ===== End CTA (plan cta-states) ===== *\/\n .bd-post .bp-cta-end { background: var(--inverse-bg); padding: 40px 32px; display: flex; flex-direction: column; align-items: center; gap: 16px; margin: var(--gap-section) 0; }\n .bd-post .bp-cta-end-title { font-family: \"Roboto\", sans-serif; font-weight: 700; font-size: 26px; line-height: 1.2; color: var(--inverse-text); text-align: center; margin: 0; }\n .bd-post .bp-cta-end-sub { font-size: 16px; color: var(--inverse-text-2); text-align: center; max-width: 560px; margin: 0; }\n .bd-post .bp-cta-end-btn {\n display: inline-flex; align-items: center; gap: 8px;\n background: var(--accent-hot); color: var(--btn-ink);\n font-family: \"Manrope\", sans-serif; font-weight: 700; font-size: 16px; line-height: 1.2;\n padding: 12px 28px; border-radius: 8px; text-decoration: none;\n border: none; cursor: pointer;\n }\n .bd-post .bp-cta-end-btn svg { width: 16px; height: 16px; }\n .bd-post .bp-cta-end-btn:hover { background: var(--btn-white); color: var(--btn-ink); }\n\n \/* ===== References ===== *\/\n .bd-post .bd-refs-title { font-weight: 700; font-size: 15px; color: var(--text-primary); margin: 48px 0 12px; }\n .bd-post .bd-refs { font-size: 14px; color: var(--text-secondary); padding-left: 1.5em; }\n .bd-post .bd-refs li { margin-bottom: 6px; }\n .bd-post .bd-refs li a { color: var(--accent-text); text-decoration: underline; }\n .bd-post .bd-refs li a:hover { color: var(--accent-hover); }\n\n \/* ===== Motion (sanctioned set, gated) ===== *\/\n @media (prefers-reduced-motion: no-preference) {\n @supports (animation-timeline: view()) {\n .bd-post .bd-reveal { animation: bd-fade-in linear both; animation-timeline: view(); animation-range: entry 0% entry 35%; }\n @keyframes bd-fade-in { from { opacity: 0; } to { opacity: 1; } }\n }\n .bd-post h2 { transition: color .2s ease-out, transform .2s ease-out; }\n .bd-post h2:hover { color: var(--accent-text); transform: scale(1.02); }\n .bd-post .bd-post-article a { transition: color .2s ease-out, text-decoration-color .2s ease-out; }\n .bd-post .bp-specnote-card, .bd-post .bp-takeaway-card { transition: transform .2s ease-out, box-shadow .2s ease-out; }\n .bd-post .bp-specnote-card:hover, .bd-post .bp-takeaway-card:hover { transform: translateY(-2px); box-shadow: 0 6px 18px rgba(0,0,0,0.08); }\n .bd-post .bp-takeaway-row { transition: color .2s ease-out; }\n .bd-post .bp-takeaway-row:hover .bp-takeaway-text { color: var(--accent-on-tint); }\n .bd-post .bp-cta-end-btn { transition: background .2s ease-out, color .2s ease-out, transform .2s ease-out; }\n .bd-post .bp-cta-end-btn:hover { transform: translateY(-2px); }\n }\n\n @media (max-width: 767px) {\n .bd-post { padding: 16px; }\n .bd-post h1 { font-size: 22px; }\n .bd-post h2 { font-size: 26px; margin-top: 32px; }\n .bd-post h3 { font-size: 20px; margin-top: 24px; }\n .bd-post .bp-specnote-cells { flex-direction: column; gap: 0; }\n .bd-post .bp-specnote-cell + .bp-specnote-cell { border-left: none; border-top: 1px solid var(--card-border); padding-left: 0; padding-top: 16px; margin-top: 16px; }\n .bd-post .bp-cta-end { padding: 24px 16px; }\n .bd-post .bp-cta-end-title { font-size: 20px; }\n }\n <\/style>\n <article class=\"bd-post-article\">\n\n <p>B\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u1ee7a m\u1ed9t b\u1ed9 ngu\u1ed3n cho bi\u1ebft \u0111\u1ed9 g\u1ee3n l\u00e0 \u201c\u2264100 mVp-p\u201d. B\u1ea1n k\u1ebft n\u1ed1i m\u00e1y hi\u1ec7n s\u00f3ng v\u1edbi \u0111\u1ea7u ra v\u00e0 th\u1ea5y d\u1ea1ng s\u00f3ng tr\u00f4ng ho\u00e0n to\u00e0n kh\u00e1c v\u1edbi d\u1ea1ng s\u00f3ng r\u0103ng c\u01b0a 100 mV s\u1ea1ch, trong khi m\u1ed9t ng\u01b0\u1eddi \u0111am m\u00ea \u0111i\u1ec7n t\u1eed \u1edf cu\u1ed1i h\u00e0nh lang v\u1eeba \u0111o \u0111\u01b0\u1ee3c 1,4 Vp-p \u1edf m\u1ee9c 5 V tr\u00ean b\u1ed9 ngu\u1ed3n b\u00e0n m\u1edbi c\u1ee7a anh \u1ea5y v\u00e0 mu\u1ed1n bi\u1ebft li\u1ec7u n\u00f3 c\u00f3 b\u1ecb h\u1ecfng kh\u00f4ng (<a href=\"https:\/\/www.reddit.com\/r\/AskElectronics\/comments\/1gm8h7m\/what_is_acceptable_noiseripple_on_cheap\/\" target=\"_blank\" rel=\"noopener\">Reddit r\/AskElectronics<\/a>, 2025). C\u1ea3 hai b\u1ea1n \u0111\u1ec1u \u0111ang nh\u00ecn v\u00e0o c\u00f9ng m\u1ed9t trang c\u1ee7a c\u00e2u chuy\u1ec7n: t\u1eeb \u201cripple\u201d \u0111ang g\u00e1nh v\u00e1c qu\u00e1 nhi\u1ec1u \u00fd ngh\u0129a. \u0110\u1eb1ng sau n\u00f3 \u1ea9n ch\u1ee9a b\u1ed1n t\u00edn hi\u1ec7u kh\u00e1c nhau v\u1edbi b\u1ed1n nguy\u00ean nh\u00e2n kh\u00e1c nhau, b\u1ed1n v\u1ea5n \u0111\u1ec1 \u0111o l\u01b0\u1eddng kh\u00e1c nhau v\u00e0 b\u1ed1n quan ni\u1ec7m kh\u00e1c nhau v\u1ec1 m\u1ee9c \u201cch\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c\u201d. C\u1ea9m nang n\u00e0y s\u1ebd ph\u00e2n t\u00e1ch c\u00e1c y\u1ebfu t\u1ed1 \u0111\u00f3, sau \u0111\u00f3 cung c\u1ea5p cho b\u1ea1n m\u1ed9t khu\u00f4n kh\u1ed5 \u0111\u1ec3 quy\u1ebft \u0111\u1ecbnh m\u1ee9c \u0111\u1ed9 \u201cs\u1ea1ch\u201d th\u1ef1c s\u1ef1 c\u1ea7n thi\u1ebft cho \u0111\u01b0\u1eddng d\u1eabn DC c\u1ee7a b\u1ea1n.<\/p>\n <img decoding=\"async\" src=\"https:\/\/www.omch.com\/wp-content\/uploads\/2026\/09\/Power-Supply-Ripple-1.webp\" style=\"width: 512px; height: 384px; max-width: 100%; object-fit: cover; border-radius: 12px; margin: 30px auto; display: block; box-shadow: 10px 10px 60px 0px rgba(210, 221, 224, 0.35); transition: all 0.3s ease; cursor: pointer;\" onmouseover=\"this.style.transform='translateY(-5px) scale(1.03)'; this.style.boxShadow='15px 25px 80px 0px rgba(210, 221, 224, 0.45)'\" onmouseout=\"this.style.transform='translateY(0) scale(1)'; this.style.boxShadow='10px 10px 60px 0px rgba(210, 221, 224, 0.35)'\"> \n <h2>Dao \u0111\u1ed9ng ngu\u1ed3n th\u1ef1c s\u1ef1 l\u00e0 g\u00ec: B\u1ed1n t\u00edn hi\u1ec7u \u1ea9n trong \u0111\u1ea7u ra DC c\u1ee7a b\u1ea1n<\/h2>\n\n <p>Ripple l\u00e0 dao \u0111\u1ed9ng \u0111\u1ecbnh k\u1ef3 c\u00f2n l\u1ea1i c\u1ee7a \u0111i\u1ec7n \u00e1p m\u1ed9t chi\u1ec1u t\u1ea1i \u0111\u1ea7u ra c\u1ee7a b\u1ed9 ngu\u1ed3n (<a href=\"https:\/\/en.wikipedia.org\/wiki\/Ripple_(electrical)\" target=\"_blank\" rel=\"noopener\">Wikipedia, \u201cRipple (\u0111i\u1ec7n)\u201d<\/a>). \u0110\u1ecbnh ngh\u0129a \u0111\u00f3 l\u00e0 ch\u00ednh x\u00e1c nh\u01b0ng b\u1ea3n th\u00e2n n\u00f3 th\u00ec v\u00f4 d\u1ee5ng, b\u1edfi v\u00ec nh\u1eefng g\u00ec b\u1ea1n th\u1ea5y tr\u00ean m\u00e1y hi\u1ec7n s\u00f3ng kh\u00f4ng bao gi\u1edd ch\u1ec9 l\u00e0 m\u1ed9t t\u00edn hi\u1ec7u duy nh\u1ea5t. C\u00f3 b\u1ed1n th\u00e0nh ph\u1ea7n \u0111i k\u00e8m tr\u00ean \u0111\u01b0\u1eddng \u0111i\u1ec7n m\u1ed9t chi\u1ec1u \u0111\u00f3, v\u00e0 ch\u1ec9 c\u00f3 m\u1ed9t trong s\u1ed1 ch\u00fang l\u00e0 th\u1ee9 m\u00e0 c\u00e1c t\u00e0i li\u1ec7u k\u1ef9 thu\u1eadt g\u1ecdi l\u00e0 \u201cripple\u201d:<\/p>\n\n <div class=\"table-wrapper\">\n <table class=\"rich-table\">\n <thead><tr><th>Th\u00e0nh ph\u1ea7n<\/th><th>Ngu\u1ed3n<\/th><th>T\u1ea7n s\u1ed1<\/th><th>Trong th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u1ee7a b\u1ea3ng d\u1eef li\u1ec7u?<\/th><th>Ai l\u00e0 ng\u01b0\u1eddi ph\u1ea3i g\u00e1nh ch\u1ecbu h\u1eadu qu\u1ea3<\/th><\/tr><\/thead>\n <tbody>\n <tr><td>C\u1eb7n trong \u0111\u01b0\u1eddng \u1ed1ng ch\u00ednh<\/td><td>L\u1ecdc ngu\u1ed3n tuy\u1ebfn t\u00ednh \u1edf t\u1ea7n s\u1ed1 50\/60 Hz<\/td><td>50\/60 Hz + s\u00f3ng h\u00e0i<\/td><td>C\u00f3 (ngu\u1ed3n \u0111i\u1ec7n tuy\u1ebfn t\u00ednh)<\/td><td>thi\u1ebft b\u1ecb \u00e2m thanh v\u00e0 ph\u00e1t thanh (ti\u1ebfng \u00f9), c\u00e1c lo\u1ea1i kh\u00e1c hi\u1ebfm khi<\/td><\/tr>\n <tr><td>Dao \u0111\u1ed9ng chuy\u1ec3n m\u1ea1ch<\/td><td>chuy\u1ec3n m\u1ea1ch c\u01a1 b\u1ea3n th\u00f4ng qua b\u1ed9 l\u1ecdc \u0111\u1ea7u ra<\/td><td>t\u1eeb h\u00e0ng ch\u1ee5c kHz \u0111\u1ebfn d\u1ea3i t\u1ea7n s\u1ed1 MHz th\u1ea5p<\/td><td>C\u00f3 (theo h\u1ea7u h\u1ebft c\u00e1c th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u1ee7a SMPS)<\/td><td>c\u00f4ng c\u1ee5 so s\u00e1nh th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt<\/td><\/tr>\n <tr><td>C\u00e1c \u0111\u1ec9nh nhi\u1ec5u do chuy\u1ec3n m\u1ea1ch<\/td><td>hi\u1ec7n t\u01b0\u1ee3ng gh\u00e9p n\u1ed1i k\u00fd sinh c\u1ee7a c\u00e1c c\u1ea1nh chuy\u1ec3n m\u1ea1ch nhanh<\/td><td>b\u0103ng th\u00f4ng r\u1ed9ng MHz+<\/td><td>hi\u1ebfm khi<\/td><td>thi\u1ebft b\u1ecb t\u01b0\u01a1ng t\u1ef1, c\u1ea3m bi\u1ebfn, b\u00e1nh r\u0103ng ch\u00ednh x\u00e1c<\/td><\/tr>\n <tr><td>D\u00f2ng \u0111i\u1ec7n tho\u00e1ng qua v\u00e0 d\u00f2ng \u0111i\u1ec7n ti\u00eam v\u00e0o<\/td><td>c\u00e1c b\u01b0\u1edbc t\u1ea3i, ph\u1ea3n \u1ee9ng c\u1ea3m \u1ee9ng, \u0111\u1ed9ng c\u01a1\/c\u00f4ng t\u1eafc t\u01a1<\/td><td>c\u00e1c s\u1ef1 ki\u1ec7n ch\u1ec9 di\u1ec5n ra m\u1ed9t l\u1ea7n<\/td><td>kh\u00f4ng<\/td><td>thi\u1ebft b\u1ecb hi\u1ec7n tr\u01b0\u1eddng<\/td><\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <p>T\u1ea1i sao vi\u1ec7c ph\u00e2n chia n\u00e0y l\u1ea1i quan tr\u1ecdng? B\u1ed1n th\u00e0nh ph\u1ea7n n\u00e0y ch\u00eanh l\u1ec7ch v\u1ec1 t\u1ea7n s\u1ed1 t\u1eeb ba \u0111\u1ebfn b\u1ed1n b\u1eadc \u0111\u1ed9 l\u1edbn, ch\u00fang c\u1ea7n c\u00e1c thi\u1ebft l\u1eadp \u0111o l\u01b0\u1eddng kh\u00e1c nhau, g\u00e2y h\u01b0 h\u1ecfng cho c\u00e1c t\u1ea3i kh\u00e1c nhau, v\u00e0 m\u1ed9t gi\u1edbi h\u1ea1n duy nh\u1ea5t \u201c\u2264100 mVp-p\u201d ch\u1ec9 bao ph\u1ee7 ch\u00ednh x\u00e1c m\u1ed9t trong s\u1ed1 ch\u00fang. H\u1ec7 s\u1ed1 g\u1ee3n (ripple factor \u2013 t\u1ef7 l\u1ec7 RMS c\u0169 RF = V~AC \/ V~DC) c\u0169ng ch\u1ec9 m\u00f4 t\u1ea3 ph\u1ea7n dao \u0111\u1ed9ng \u0111\u1ecbnh k\u1ef3 m\u01b0\u1ee3t m\u00e0, v\u00e0 v\u00ec \u0111\u00e2y l\u00e0 t\u1ef7 l\u1ec7 RMS n\u00ean n\u00f3 lu\u00f4n tr\u00f4ng l\u1edbn h\u01a1n con s\u1ed1 mVp-p m\u00e0 m\u1ecdi ng\u01b0\u1eddi th\u01b0\u1eddng tr\u00edch d\u1eabn ng\u00e0y nay. \u0110\u00f3 l\u00e0 l\u00fd do t\u1ea1i sao hai gi\u00e1 tr\u1ecb n\u00e0y d\u01b0\u1eddng nh\u01b0 kh\u00f4ng bao gi\u1edd kh\u1edbp nhau.<\/p>\n\n <p>M\u1ed9t ch\u00fat l\u1ea1c \u0111\u1ec1, v\u00ec k\u1ebft qu\u1ea3 t\u00ecm ki\u1ebfm c\u1ee9 li\u00ean t\u1ee5c \u0111\u1ec1 c\u1eadp \u0111\u1ebfn kh\u00e1i ni\u1ec7m n\u00e0y: \u201cdao \u0111\u1ed9ng c\u1ee7a m\u00e1y ph\u00e1t \u0111i\u1ec7n\u201d \u2014 th\u00e0nh ph\u1ea7n d\u00f2ng \u0111i\u1ec7n xoay chi\u1ec1u trong \u0111\u1ea7u ra s\u1ea1c c\u1ee7a \u00f4 t\u00f4 m\u00e0 c\u00e1c k\u1ef9 thu\u1eadt vi\u00ean ki\u1ec3m tra \u0111\u1ec3 \u0111\u00e1nh gi\u00e1 t\u00ecnh tr\u1ea1ng c\u1ee7a \u0111i-\u1ed1t \u2014 l\u00e0 m\u1ed9t th\u00f4ng s\u1ed1 \u0111o l\u01b0\u1eddng kh\u00e1c thu\u1ed9c v\u1ec1 m\u1ed9t h\u1ec7 th\u1ed1ng kh\u00e1c. C\u00f9ng m\u1ed9t t\u1eeb, nh\u01b0ng thu\u1ed9c l\u0129nh v\u1ef1c kh\u00e1c; h\u01b0\u1edbng d\u1eabn n\u00e0y ch\u1ec9 t\u1eadp trung v\u00e0o c\u00e1c b\u1ed9 ngu\u1ed3n.<\/p>\n\n <h2>C\u00e1ch \u0111o \u0111\u1ed9 g\u1ee3n c\u1ee7a ngu\u1ed3n \u0111i\u1ec7n: L\u1ea5y \u0111\u01b0\u1ee3c con s\u1ed1 \u0111\u00e1ng tin c\u1eady<\/h2>\n\n <p>H\u1ea7u h\u1ebft c\u00e1c gi\u00e1 tr\u1ecb \u201cripple x\u1ea5u\u201d \u0111\u1ec1u l\u00e0 k\u1ebft qu\u1ea3 \u0111o kh\u00f4ng ch\u00ednh x\u00e1c. C\u00f3 ba th\u00f4ng s\u1ed1 quy\u1ebft \u0111\u1ecbnh li\u1ec7u con s\u1ed1 \u0111\u00f3 c\u00f3 \u00fd ngh\u0129a g\u00ec hay kh\u00f4ng:<\/p>\n\n <ul>\n <li><strong>Kh\u1edbp n\u1ed1i:<\/strong> S\u1eed d\u1ee5ng gh\u00e9p n\u1ed1i AC \u0111\u1ec3 ng\u0103n ch\u1eb7n th\u00e0nh ph\u1ea7n DC v\u00e0 ch\u1ec9 khu\u1ebfch \u0111\u1ea1i th\u00e0nh ph\u1ea7n d\u01b0. C\u00f3 m\u1ed9t s\u1ed1 l\u01b0\u1ee3ng \u0111\u00e1ng ng\u1ea1c nhi\u00ean c\u00e1c t\u00e0i li\u1ec7u h\u01b0\u1edbng d\u1eabn l\u1ea1i qu\u00ean \u0111\u1ec1 c\u1eadp \u0111\u1ebfn \u0111i\u1ec1u n\u00e0y (<a href=\"https:\/\/www.eevblog.com\/forum\/beginners\/measure-power-supply-ripple-with-this-technique\/\" target=\"_blank\" rel=\"noopener\">Di\u1ec5n \u0111\u00e0n EEVblog<\/a>, 2021).<\/li>\n <li><strong>B\u0103ng th\u00f4ng:<\/strong> Gi\u1edbi h\u1ea1n 20 MHz tr\u00ean nhi\u1ec1u m\u00e1y hi\u1ec7n s\u00f3ng xu\u1ea5t ph\u00e1t t\u1eeb c\u00e1c ti\u00eau chu\u1ea9n ki\u1ec3m tra c\u0169. Gi\u1edbi h\u1ea1n n\u00e0y che gi\u1ea5u c\u00e1c th\u00e0nh ph\u1ea7n t\u1ea7n s\u1ed1 cao, c\u00f3 d\u1ea1ng \u0111\u1ec9nh nh\u1ecdn c\u1ee7a c\u00e1c b\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch hi\u1ec7n \u0111\u1ea1i. N\u1ebfu b\u1ea1n \u0111ang so s\u00e1nh v\u1edbi b\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt, h\u00e3y s\u1eed d\u1ee5ng c\u00f9ng b\u0103ng th\u00f4ng m\u00e0 nh\u00e0 s\u1ea3n xu\u1ea5t \u0111\u00e3 d\u00f9ng (th\u01b0\u1eddng l\u00e0 20 MHz); n\u1ebfu b\u1ea1n \u0111ang t\u00ecm ki\u1ebfm m\u1ed9t s\u1ef1 c\u1ed1 th\u1ef1c t\u1ebf, h\u00e3y m\u1edf r\u1ed9ng b\u0103ng th\u00f4ng t\u1ed1i \u0111a. S\u1ef1 th\u1eadt c\u00f3 th\u1ec3 tr\u00f4ng r\u1ea5t \u0111\u00e1ng s\u1ee3.<\/li>\n <li><strong>K\u1ebft n\u1ed1i \u0111\u1ea7u d\u00f2:<\/strong> D\u00e2y n\u1ed1i \u0111\u1ea5t d\u00e0i tr\u00ean \u0111\u1ea7u d\u00f2 ti\u00eau chu\u1ea9n \u0111\u00f3ng vai tr\u00f2 nh\u01b0 m\u1ed9t \u0103ng-ten. V\u00f2ng l\u1eb7p n\u1ed1i \u0111\u1ea5t c\u1ee7a n\u00f3 thu nh\u1eadn c\u00e1c tr\u01b0\u1eddng t\u1eeb do d\u00f2ng \u0111i\u1ec7n chuy\u1ec3n m\u1ea1ch t\u1ea1o ra v\u00e0 hi\u1ec3n th\u1ecb c\u00e1c \u0111\u1ec9nh gi\u1ea3. Ch\u00ednh v\u00ec l\u00fd do \u0111\u00f3 m\u00e0 c\u00e2u n\u00f3i \u201cT\u00f4i \u0111\u00e3 th\u00eam t\u1ee5 \u0111i\u1ec7n nh\u01b0ng \u0111\u1ed9 g\u1ee3n v\u1eabn cao\u201d th\u01b0\u1eddng l\u00e0 do v\u1ea5n \u0111\u1ec1 \u1edf \u0111\u1ea7u d\u00f2, ch\u1ee9 kh\u00f4ng ph\u1ea3i do b\u1ed9 ngu\u1ed3n (<a href=\"https:\/\/electronics.stackexchange.com\/questions\/707711\/switching-power-supply-has-high-ripple-voltage-no-matter-how-many-capacitors-are\" target=\"_blank\" rel=\"noopener\">StackExchange v\u1ec1 \u0110i\u1ec7n t\u1eed<\/a>, 2024). S\u1eed d\u1ee5ng k\u1ebft n\u1ed1i \u0111\u1ea7u v\u00e0 th\u00e2n, n\u1ed1i \u0111\u1ea5t b\u1eb1ng k\u1eb9p gi\u1ea5y ho\u1eb7c \u0111\u1ea7u n\u1ed1i \u0111\u1ed3ng tr\u1ee5c 50 \u03a9 g\u1ea7n t\u1ee5 \u0111i\u1ec7n \u0111\u1ea7u ra (<a href=\"https:\/\/www.analog.com\/en\/resources\/app-notes\/an-1144.html\" target=\"_blank\" rel=\"noopener\">Analog Devices AN-1144<\/a>).<\/li>\n <\/ul>\n\n \n <div class=\"rich-checklist\">\n <p class=\"rich-checklist-title\"><span class=\"rich-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"m3 17 2 2 4-4\"\/><path d=\"m3 7 2 2 4-4\"\/><path d=\"M13 6h8\"\/><path d=\"M13 12h8\"\/><path d=\"M13 18h8\"\/><\/svg><\/span>Tr\u01b0\u1edbc khi tin t\u01b0\u1edfng v\u00e0o m\u1ed9t k\u1ebft qu\u1ea3 \u0111o s\u00f3ng g\u1ee3n<\/p>\n <ul class=\"rich-checklist-list\">\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>K\u1ebft n\u1ed1i c\u1eb7p AC cho k\u00eanh m\u00e1y hi\u1ec7n s\u00f3ng<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>R\u00fat ng\u1eafn \u0111\u01b0\u1eddng d\u1eabn n\u1ed1i \u0111\u1ea5t (ki\u1ec3u \u0111\u1ea7u v\u00e0 th\u00e2n, ki\u1ec3u k\u1eb9p gi\u1ea5y ho\u1eb7c \u0111\u1ea7u n\u1ed1i 50 \u03a9 t\u1ea1i t\u1ee5 \u0111i\u1ec7n \u0111\u1ea7u ra)<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>N\u1ebfu b\u1ea1n \u0111ang so s\u00e1nh v\u1edbi th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt, h\u00e3y \u0111\u1ea3m b\u1ea3o b\u0103ng th\u00f4ng c\u1ee7a nh\u00e0 cung c\u1ea5p ph\u00f9 h\u1ee3p v\u1edbi th\u00f4ng s\u1ed1 \u0111\u00f3<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>H\u00e3y m\u1edf to\u00e0n b\u1ed9 b\u0103ng th\u00f4ng n\u1ebfu b\u1ea1n \u0111ang theo d\u00f5i c\u00e1c \u0111\u1ec9nh \u0111\u1ed9t bi\u1ebfn<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>H\u00e3y quan s\u00e1t nhi\u1ec1u chu k\u1ef3 chuy\u1ec3n m\u1ea1ch, ch\u1ee9 kh\u00f4ng ch\u1ec9 m\u1ed9t chu k\u1ef3<\/li>\n <\/ul>\n <\/div>\n\n <p>C\u00f3 m\u1ed9t lo\u1ea1i nh\u1ea1c c\u1ee5 c\u1ea7n c\u00f3 c\u1ea3nh b\u00e1o ri\u00eang.<\/p>\n\n <p>\u0110\u00f3 l\u00e0 th\u1ee9 m\u00e0 h\u1ea7u h\u1ebft m\u1ecdi ng\u01b0\u1eddi th\u01b0\u1eddng ch\u1ecdn \u0111\u1ea7u ti\u00ean:<\/p>\n\n \n <div class=\"rich-callout\">\n <span class=\"rich-callout-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"m21.73 18-8-14a2 2 0 0 0-3.48 0l-8 14A2 2 0 0 0 4 20h16a2 2 0 0 0 1.73-2Z\"\/><path d=\"M12 9v4\"\/><path d=\"M12 17h.01\"\/><\/svg><\/span>\n <p>M\u1ed9t \u0111\u1ed3ng h\u1ed3 v\u1ea1n n\u0103ng \u1edf ch\u1ebf \u0111\u1ed9 \u0111o \u0111i\u1ec7n \u00e1p xoay chi\u1ec1u (AC) kh\u00f4ng th\u1ec3 cung c\u1ea5p cho b\u1ea1n th\u00f4ng s\u1ed1 v\u1ec1 \u0111\u1ed9 g\u1ee3n. D\u1ea3i t\u1ea7n s\u1ed1 v\u00e0 ph\u01b0\u01a1ng ph\u00e1p t\u00ednh trung b\u00ecnh RMS c\u1ee7a n\u00f3 l\u00e0m m\u1edd \u0111i c\u00e1c \u0111\u1ec9nh \u0111i\u1ec7n \u00e1p do chuy\u1ec3n m\u1ea1ch v\u00e0 \u0111\u1ed9 g\u1ee3n, bi\u1ebfn ch\u00fang th\u00e0nh m\u1ed9t con s\u1ed1 v\u00f4 ngh\u0129a. Ch\u1ec9 n\u00ean s\u1eed d\u1ee5ng n\u00f3 nh\u01b0 m\u1ed9t c\u00e1ch ki\u1ec3m tra s\u01a1 b\u1ed9 \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh \u201cc\u00f3 d\u00f2ng \u0111i\u1ec7n hay kh\u00f4ng\u201d.<\/p>\n <\/div>\n\n <p>M\u1eb9o \u201chai t\u1ee5 \u0111i\u1ec7n \u1edf \u0111\u1ea7u d\u00e2y c\u00e1p\u201d \u0111ang lan truy\u1ec1n tr\u00ean c\u00e1c n\u1ec1n t\u1ea3ng video l\u00e0 m\u1ed9t quy\u1ebft \u0111\u1ecbnh t\u00f9y theo t\u1eebng tr\u01b0\u1eddng h\u1ee3p: n\u00f3 m\u00f4 ph\u1ecfng m\u1ed9t t\u1ea3i \u0111\u01b0\u1ee3c k\u1ebft n\u1ed1i, \u0111i\u1ec1u n\u00e0y th\u1ef1c t\u1ebf h\u01a1n so v\u1edbi vi\u1ec7c ch\u1ec9 s\u1eed d\u1ee5ng ngu\u1ed3n \u0111i\u1ec7n tr\u1ea7n, nh\u01b0ng n\u00f3 c\u0169ng l\u1ecdc b\u1edbt m\u1ed9t s\u1ed1 th\u00f4ng tin m\u00e0 b\u1ea1n th\u1ef1c s\u1ef1 c\u1ea7n quan s\u00e1t (<a href=\"https:\/\/www.eevblog.com\/forum\/beginners\/measure-power-supply-ripple-with-this-technique\/\" target=\"_blank\" rel=\"noopener\">Di\u1ec5n \u0111\u00e0n EEVblog<\/a>, 2021). Tr\u01b0\u1edbc ti\u00ean, h\u00e3y quy\u1ebft \u0111\u1ecbnh xem b\u1ea1n \u0111ang theo \u0111u\u1ed5i t\u00edn hi\u1ec7u n\u00e0o trong b\u1ed1n t\u00edn hi\u1ec7u \u0111\u00f3. Sau \u0111\u00f3, h\u00e3y ch\u1ecdn ph\u01b0\u01a1ng \u00e1n giao d\u1ecbch cho ph\u00e9p t\u00edn hi\u1ec7u \u0111\u00f3 \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n.<\/p>\n\n <h2>M\u1ee9c \u0111\u1ed9 dao \u0111\u1ed9ng c\u1ee7a ngu\u1ed3n \u0111i\u1ec7n n\u00e0o l\u00e0 ch\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c? \u0110i\u1ec1u n\u00e0y ph\u1ee5 thu\u1ed9c v\u00e0o t\u1ea3i<\/h2>\n\n <p>H\u00e3y h\u1ecfi \u201cm\u1ee9c dao \u0111\u1ed9ng n\u00e0o l\u00e0 ch\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c\u201d v\u00e0 b\u1ea1n s\u1ebd nh\u1eadn \u0111\u01b0\u1ee3c nh\u1eefng c\u00e2u tr\u1ea3 l\u1eddi m\u00e2u thu\u1eabn nhau: miliv\u00f4n tuy\u1ec7t \u0111\u1ed1i (ti\u00eau chu\u1ea9n ATX cho ph\u00e9p 120 mVp-p tr\u00ean \u0111\u01b0\u1eddng +12 V v\u00e0 50 mVp-p tr\u00ean c\u00e1c \u0111\u01b0\u1eddng 5 V\/3,3 V, theo <a href=\"https:\/\/www.tomshardware.com\/reviews\/how-we-test-psu,4042-5.html\" target=\"_blank\" rel=\"noopener\">Tom\u2019s Hardware<\/a>), t\u1ef7 l\u1ec7 ph\u1ea7n tr\u0103m (1% l\u00e0 m\u1ed9t quy t\u1eafc kinh nghi\u1ec7m ph\u1ed5 bi\u1ebfn; theo c\u00e1c c\u1ea9m nang c\u1ee7a ARRL, tr\u01b0\u1edbc \u0111\u00e2y th\u01b0\u1eddng khuy\u1ebfn ngh\u1ecb t\u1ef7 l\u1ec7 cao h\u01a1n 5% \u0111\u1ed1i v\u1edbi b\u1ed9 ph\u00e1t CW v\u00e0 3% \u0111\u1ed1i v\u1edbi ngu\u1ed3n c\u1ea5p c\u1ef1c d\u01b0\u01a1ng c\u1ee7a b\u1ed9 khu\u1ebfch \u0111\u1ea1i tuy\u1ebfn t\u00ednh, theo <a href=\"https:\/\/wsjtx.groups.io\/g\/main\/topic\/acceptable_pa_power_supply\/71775932\" target=\"_blank\" rel=\"noopener\">WSJT-X tr\u00ean groups.io<\/a>, 2021), v\u00e0 h\u1ec7 s\u1ed1 dao \u0111\u1ed9ng. Kh\u00f4ng c\u00f3 y\u1ebfu t\u1ed1 n\u00e0o trong s\u1ed1 \u0111\u00f3 l\u00e0 sai; m\u1ed7i y\u1ebfu t\u1ed1 \u0111o l\u01b0\u1eddng m\u1ed9t \u0111\u1ea1i l\u01b0\u1ee3ng kh\u00e1c nhau \u0111\u1ed1i v\u1edbi t\u1eebng lo\u1ea1i t\u1ea3i kh\u00e1c nhau. Khung ph\u00e2n t\u00edch duy nh\u1ea5t c\u00f3 th\u1ec3 \u0111\u1ee9ng v\u1eefng tr\u01b0\u1edbc th\u1ef1c t\u1ebf l\u00e0 c\u00e1ch ti\u1ebfp c\u1eadn d\u1ef1a tr\u00ean lo\u1ea1i t\u1ea3i m\u00e0 b\u1ea1n \u0111ang c\u1ea5p ngu\u1ed3n.<\/p>\n\n <h3>B\u1ed1n m\u1ee9c t\u1ea3i: Ai quan t\u00e2m, v\u00e0 m\u1ee9c \u0111\u1ed9 quan t\u00e2m ra sao?<\/h3>\n\n <ul>\n <li><strong>C\u01a1 ch\u1ebf k\u00edch ho\u1ea1t v\u00e0 kh\u1ea3 n\u0103ng ch\u1ed1ng nhi\u1ec5u (cu\u1ed9n d\u00e2y r\u01a1le, \u0111\u00e8n, m\u00e1y b\u01a1m, t\u1ee7 c\u00f4ng t\u1eafc t\u01a1):<\/strong> S\u1ef1 dao \u0111\u1ed9ng \u1edf \u0111\u00e2y v\u1ec1 c\u01a1 b\u1ea3n l\u00e0 kh\u00f4ng \u0111\u00e1ng k\u1ec3. C\u00e1c t\u1ea3i n\u00e0y c\u00f3 bi\u00ean \u0111\u1ed9 ho\u1ea1t \u0111\u1ed9ng r\u1ea5t l\u1edbn; m\u1ed9t dao \u0111\u1ed9ng 100 mV tr\u00ean \u0111\u01b0\u1eddng ray 24 V l\u00e0 chuy\u1ec7n nh\u1ecf \u0111\u1ed1i v\u1edbi ch\u00fang.<\/li>\n <li><strong>Logic s\u1ed1:<\/strong> H\u1ea7u h\u1ebft c\u00e1c bo m\u1ea1ch logic \u0111\u1ec1u c\u00f3 c\u01a1 ch\u1ebf \u0111i\u1ec1u ch\u1ec9nh n\u1ed9i b\u1ed9 ri\u00eang, gi\u00fap h\u1ea5p th\u1ee5 dao \u0111\u1ed9ng tr\u00ean \u0111\u01b0\u1eddng c\u1ea5p ngu\u1ed3n tr\u01b0\u1edbc khi n\u00f3 t\u00e1c \u0111\u1ed9ng \u0111\u1ebfn chip b\u00e1n d\u1eabn. \u0110i\u1ec1u th\u1ef1c s\u1ef1 g\u00e2y h\u1ea1i cho bo m\u1ea1ch logic l\u00e0 hi\u1ec7n t\u01b0\u1ee3ng s\u1ee5t \u00e1p t\u1ea1m th\u1eddi t\u1ea1i \u0111i\u1ec3m t\u1ea3i. \u0110\u00f3 l\u00e0 m\u1ed9t v\u1ea5n \u0111\u1ec1 t\u1ea1m th\u1eddi, ch\u1ee9 kh\u00f4ng ph\u1ea3i v\u1ea5n \u0111\u1ec1 li\u00ean quan \u0111\u1ebfn th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt v\u1ec1 dao \u0111\u1ed9ng.<\/li>\n <li><strong>\u0110o l\u01b0\u1eddng t\u01b0\u01a1ng t\u1ef1 v\u00e0 thu th\u1eadp d\u1eef li\u1ec7u:<\/strong> M\u1ea1ch v\u00f2ng 4\u201320 mA, b\u1ed9 truy\u1ec1n t\u00edn hi\u1ec7u, b\u1ed9 ti\u1ec1n x\u1eed l\u00fd ADC. \u1ede \u0111\u00e2y, \u0111\u1ed9 g\u1ee3n tr\u1ef1c ti\u1ebfp \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn gi\u1edbi h\u1ea1n sai s\u1ed1. M\u1ed9t nguy\u00ean t\u1eafc kinh nghi\u1ec7m \u0111\u01b0\u1ee3c c\u00e1c k\u1ef9 s\u01b0 th\u1ef1c t\u1ebf \u0111\u1ec1 c\u1eadp l\u00e0 m\u1ee9c 30 mV c\u00f3 th\u1ec3 ch\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c cho c\u00e1c \u1ee9ng d\u1ee5ng th\u00f4ng th\u01b0\u1eddng, nh\u01b0ng l\u1ea1i qu\u00e1 cao \u0111\u1ed1i v\u1edbi m\u1ea1ch logic ch\u00ednh x\u00e1c \u0111i\u1ec7n \u00e1p th\u1ea5p \u1edf m\u1ee9c 1,8 V (<a href=\"https:\/\/electronics.stackexchange.com\/questions\/501187\/output-voltage-ripple-considerations\" target=\"_blank\" rel=\"noopener\">StackExchange v\u1ec1 \u0110i\u1ec7n t\u1eed<\/a>, 2020); c\u00e1ch suy lu\u1eadn n\u00e0y c\u0169ng \u00e1p d\u1ee5ng \u0111\u01b0\u1ee3c cho b\u1ea5t k\u1ef3 m\u1ea1ch \u0111\u1ea7u v\u00e0o t\u01b0\u01a1ng t\u1ef1 n\u00e0o m\u00e0 \u0111i\u1ec7n \u00e1p tham chi\u1ebfu v\u00e0 t\u00edn hi\u1ec7u c\u00f9ng chia s\u1ebb c\u00f9ng m\u1ed9t c\u1ef1c.<\/li>\n <li><strong>T\u1ea7n s\u1ed1 v\u00f4 tuy\u1ebfn (RF) v\u00e0 \u00e2m thanh:<\/strong> d\u1ea3i t\u1ea7n kh\u00f3 kh\u0103n nh\u1ea5t, n\u01a1i hi\u1ec7n t\u01b0\u1ee3ng g\u1ee3n s\u00f3ng v\u00e0 nhi\u1ec5u bi\u1ebfn th\u00e0nh ti\u1ebfng \u00f9 v\u00e0 c\u00e1c \u0111\u1ec9nh nhi\u1ec5u. \u0110\u00e2y ch\u00ednh l\u00e0 th\u1ebf gi\u1edbi c\u1ee7a c\u00e1c t\u1ef7 l\u1ec7 ph\u1ea7n tr\u0103m ARRL n\u00eau tr\u00ean.<\/li>\n <\/ul>\n\n <h3>T\u1ea1i sao ba thang \u0111o \u201cc\u00f3 th\u1ec3 ch\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c\u201d n\u00e0y l\u1ea1i kh\u00f4ng bao gi\u1edd tr\u00f9ng kh\u1edbp v\u1edbi nhau<\/h3>\n\n <p>Millivolt, ph\u1ea7n tr\u0103m v\u00e0 h\u1ec7 s\u1ed1 dao \u0111\u1ed9ng \u0111o l\u01b0\u1eddng c\u00e1c \u0111\u1ea1i l\u01b0\u1ee3ng kh\u00e1c nhau tr\u00ean c\u00e1c \u0111\u01b0\u1eddng ngu\u1ed3n kh\u00e1c nhau. Dao \u0111\u1ed9ng 100 mV t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi 2% tr\u00ean \u0111\u01b0\u1eddng ngu\u1ed3n 5 V v\u00e0 0,4% tr\u00ean \u0111\u01b0\u1eddng ngu\u1ed3n 24 V. C\u00f9ng m\u1ed9t gi\u00e1 tr\u1ecb v\u1eadt l\u00fd l\u1ea1i \u0111\u01b0a ra nh\u1eefng k\u1ebft lu\u1eadn tr\u00e1i ng\u01b0\u1ee3c t\u00f9y thu\u1ed9c v\u00e0o thang \u0111o m\u00e0 b\u1ea1n tham chi\u1ebfu. H\u1ec7 s\u1ed1 dao \u0111\u1ed9ng c\u00e0ng l\u00e0m t\u00ecnh h\u00ecnh t\u1ed3i t\u1ec7 h\u01a1n: v\u00ec \u0111\u00e2y l\u00e0 t\u1ef7 l\u1ec7 RMS, m\u1ed9t ngu\u1ed3n \u0111i\u1ec7n tr\u00f4ng c\u00f3 v\u1ebb l\u00fd t\u01b0\u1edfng v\u1edbi gi\u00e1 tr\u1ecb \u201c0,07\u201d (7%) theo thang \u0111o n\u00e0y l\u1ea1i tr\u1edf n\u00ean \u0111\u00e1ng lo ng\u1ea1i khi so s\u00e1nh v\u1edbi \u0111\u01b0\u1eddng \u0111i\u1ec7n c\u00f3 bi\u00ean \u0111\u1ed9 \u0111\u1ec9nh-\u0111\u1ec9nh 50 mVp-p. Tr\u01b0\u1edbc khi so s\u00e1nh b\u1ea5t k\u1ef3 hai con s\u1ed1 n\u00e0o, h\u00e3y \u0111\u1eb7t ch\u00fang tr\u00ean c\u00f9ng m\u1ed9t \u0111\u01b0\u1eddng \u0111i\u1ec7n, c\u00f9ng m\u1ed9t thang \u0111o v\u00e0 trong c\u00f9ng \u0111i\u1ec1u ki\u1ec7n. H\u1ea7u h\u1ebft c\u00e1c \u201cl\u1eddi khuy\u00ean m\u00e2u thu\u1eabn\u201d s\u1ebd bi\u1ebfn m\u1ea5t khi b\u1ea1n l\u00e0m nh\u01b0 v\u1eady.<\/p>\n\n <h3>M\u1ed9t ma tr\u1eadn l\u00e0m vi\u1ec7c d\u00e0nh ri\u00eang cho h\u1ec7 th\u1ed1ng Rails c\u1ee7a b\u1ea1n<\/h3>\n\n <p><strong>To\u00e0n b\u1ed9 khung l\u00fd thuy\u1ebft g\u00f3i g\u1ecdn trong m\u1ed9t c\u00e2u: m\u1ed9t thanh ray ho\u00e0n to\u00e0n ph\u00f9 h\u1ee3p v\u1edbi t\u1ee7 r\u01a1le l\u1ea1i c\u00f3 th\u1ec3 l\u00e0 nguy\u00ean nh\u00e2n khi\u1ebfn b\u1ed9 truy\u1ec1n t\u00edn hi\u1ec7u 4\u201320 mA ho\u1ea1t \u0111\u1ed9ng kh\u00f4ng \u1ed5n \u0111\u1ecbnh. H\u00e3y x\u00e1c \u0111\u1ecbnh lo\u1ea1i t\u1ea3i tr\u01b0\u1edbc, sau \u0111\u00f3 m\u1edbi b\u00e0n \u0111\u1ebfn v\u1ea5n \u0111\u1ec1 v\u1ec1 miliv\u00f4n.<\/strong><\/p>\n\n \n <div class=\"table-wrapper\">\n <table class=\"rich-table rich-matrix\">\n <thead><tr><th>Lo\u1ea1i t\u1ea3i<\/th><th>D\u1ea3i \u0111\u1ed9 nh\u1ea1y<\/th><th>D\u1ea5u hi\u1ec7u c\u1ea7n theo d\u00f5i<\/th><th>\u201c\u0110\u1ee7 r\u1ed3i\u201d tr\u00f4ng nh\u01b0 th\u1ebf n\u00e0y<\/th><th>H\u00e0nh \u0111\u1ed9ng<\/th><\/tr><\/thead>\n <tbody>\n <tr><td>Cu\u1ed9n d\u00e2y r\u01a1le, \u0111\u00e8n, c\u00f4ng t\u1eafc t\u01a1, t\u1ee7 c\u00f4ng t\u1eafc t\u01a1<\/td><td>mi\u1ec5n d\u1ecbch<\/td><td>kh\u00f4ng c\u00f3<\/td><td>b\u1ea5t k\u1ef3 gi\u00e1 tr\u1ecb n\u00e0o \u0111\u00e3 \u0111\u01b0\u1ee3c c\u00f4ng b\u1ed1<\/td><td>Th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt h\u1ea7u nh\u01b0 kh\u00f4ng quan tr\u1ecdng (h\u00e3y ch\u1ecdn d\u1ef1a tr\u00ean gi\u00e1 c\u1ea3 v\u00e0 \u0111\u1ed9 b\u1ec1n)<\/td><\/tr>\n <tr><td>B\u1ea3ng m\u1ea1ch MCU\/b\u1ea3ng m\u1ea1ch logic<\/td><td>th\u1ea5p<\/td><td>s\u1ee5t \u00e1p nh\u1ea5t th\u1eddi, kh\u00f4ng ph\u1ea3i dao \u0111\u1ed9ng<\/td><td>trong ph\u1ea1m vi \u0111\u1ea7u v\u00e0o c\u1ee7a b\u1ed9 \u0111i\u1ec1u ch\u1ec9nh tr\u00ean bo m\u1ea1ch<\/td><td>H\u00e3y ki\u1ec3m tra quy \u0111\u1ecbnh \u0111\u1ecba ph\u01b0\u01a1ng, ch\u1ee9 kh\u00f4ng ph\u1ea3i quy \u0111\u1ecbnh c\u1ee7a \u0111\u01b0\u1eddng s\u1eaft<\/td><\/tr>\n <tr><td>M\u1ea1ch v\u00f2ng 4\u201320 mA, b\u1ed9 truy\u1ec1n t\u00edn hi\u1ec7u, b\u1ed9 ti\u1ec1n x\u1eed l\u00fd ADC<\/td><td>cao<\/td><td>s\u00f3ng g\u1ee3n + ti\u1ebfng \u1ed3n<\/td><td>c\u1ea5p \u0111\u1ed9 h\u00e0ng ch\u1ee5c mVp-p ho\u1eb7c cao h\u01a1n, \u0111\u00e3 \u0111\u01b0\u1ee3c ki\u1ec3m ch\u1ee9ng \u1edf d\u00f2ng t\u1ea3i c\u1ee7a b\u1ea1n<\/td><td>Y\u00eau c\u1ea7u th\u00f4ng s\u1ed1 t\u1ed1i \u0111a (kh\u00f4ng ph\u1ea3i gi\u00e1 tr\u1ecb \u0111i\u1ec3n h\u00ecnh), b\u0103ng th\u00f4ng v\u00e0 \u0111i\u1ec1u ki\u1ec7n t\u1ea3i<\/td><\/tr>\n <tr><td>C\u00e1c m\u1ea1ch RF \/ \u00e2m thanh<\/td><td>c\u1ef1c \u0111oan<\/td><td>s\u00f3ng g\u1ee3n + ti\u1ebfng \u1ed3n, t\u1ea5t c\u1ea3 nh\u1eefng th\u1ee9 \u0111\u00f3<\/td><td>th\u1ea5p nh\u1ea5t trong ph\u1ea1m vi ng\u00e2n s\u00e1ch cho ph\u00e9p<\/td><td>h\u00e3y thi\u1ebft k\u1ebf m\u1ed9t m\u1ea1ch \u1ed5n \u00e1p sau (LDO ho\u1eb7c LC) thay v\u00ec ch\u1ec9 d\u1ef1a v\u00e0o c\u00e1c th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt<\/td><\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <p>M\u1ed9t l\u01b0u \u00fd v\u1ec1 t\u00ednh trung th\u1ef1c: kh\u00f4ng c\u00f3 ng\u01b0\u1ee1ng chung ch\u00ednh th\u1ee9c n\u00e0o cho c\u00e1c d\u1ea3i n\u00e0y, b\u1edfi v\u00ec b\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u1ee7a t\u1eebng l\u00f4 h\u00e0ng m\u1edbi l\u00e0 ngu\u1ed3n tham kh\u1ea3o ch\u00ednh x\u00e1c nh\u1ea5t; do \u0111\u00f3, b\u1ea3ng ma tr\u1eadn ch\u1ec9 gi\u00fap b\u1ea1n x\u00e1c \u0111\u1ecbnh v\u1ecb tr\u00ed c\u1ea7n xem x\u00e9t, ch\u1ee9 kh\u00f4ng ph\u1ea3i l\u00e0 m\u1ed9t con s\u1ed1 \u0111\u1ec3 tin t\u01b0\u1edfng m\u00f9 qu\u00e1ng. V\u00e0 h\u00e3y nh\u1edb r\u1eb1ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt th\u01b0\u1eddng kh\u00f4ng \u0111\u1ec1 c\u1eadp \u0111\u1ebfn y\u1ebfu t\u1ed1 l\u00e3o h\u00f3a. Khi c\u00e1c t\u1ee5 \u0111i\u1ec7n \u0111\u1ea7u ra l\u00e3o h\u00f3a, gi\u00e1 tr\u1ecb ESR s\u1ebd t\u0103ng l\u00ean v\u00e0 kh\u1ea3 n\u0103ng l\u1ecdc suy gi\u1ea3m; do \u0111\u00f3, m\u1ed9t ngu\u1ed3n \u0111i\u1ec7n \u0111\u00e3 \u0111\u1ea1t ti\u00eau chu\u1ea9n v\u00e0o n\u0103m \u0111\u1ea7u ti\u00ean c\u00f3 th\u1ec3 tr\u1edf n\u00ean \u1ed3n \u00e0o h\u01a1n v\u00e0o n\u0103m th\u1ee9 n\u0103m. H\u00e3y g\u1ecdi \u0111\u00f3 l\u00e0 ch\u1ebf \u0111\u1ed9 h\u1ecfng h\u00f3c \u201ctr\u01b0\u1edbc \u0111\u00e2y v\u1eabn \u1ed5n\u201d.<\/p>\n\n <h2>\u0110\u1ecdc t\u00e0i li\u1ec7u k\u1ef9 thu\u1eadt Ripple: Nh\u1eefng \u0111i\u1ec1u m\u00e0 c\u00e1c s\u1ed1 li\u1ec7u trong b\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt cho bi\u1ebft v\u00e0 kh\u00f4ng cho bi\u1ebft<\/h2>\n\n <p>M\u1ed9t th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt nh\u01b0 \u201cDao \u0111\u1ed9ng v\u00e0 nhi\u1ec5u: 120 mVp-p\u201d c\u00f3 v\u1ebb t\u01b0\u01a1ng \u0111\u01b0\u01a1ng gi\u1eefa c\u00e1c nh\u00e0 cung c\u1ea5p. Tuy nhi\u00ean, th\u1ef1c t\u1ebf kh\u00f4ng ph\u1ea3i v\u1eady, cho \u0111\u1ebfn khi b\u1ea1n n\u1eafm r\u00f5 c\u00e1c \u0111i\u1ec1u ki\u1ec7n c\u1ee5 th\u1ec3.<\/p>\n\n <h3>H\u00ecnh \u1ea3nh n\u00e0y l\u00e0 \u1ea3nh ch\u1ee5p m\u1ed9t thi\u1ebft l\u1eadp th\u1eed nghi\u1ec7m<\/h3>\n\n <p>H\u00e3y l\u1ea5y m\u1ed9t d\u00f2ng s\u1ea3n ph\u1ea9m ngu\u1ed3n \u0111i\u1ec7n 75 W g\u1eafn tr\u00ean thanh DIN ph\u1ed5 bi\u1ebfn l\u00e0m v\u00ed d\u1ee5: d\u00f2ng Mean Well NDR-75 ghi r\u00f5 m\u1ee9c dao \u0111\u1ed9ng 80 mVp-p \u1edf \u0111i\u1ec7n \u00e1p \u0111\u1ea7u ra 12 V, 120 mVp-p \u1edf 24 V, v\u00e0 150 mVp-p \u1edf m\u1ee9c 48 V. \u0110i\u1ec1u m\u00e0 b\u1ea3ng th\u00f4ng s\u1ed1 c\u1ee7a nh\u00e0 ph\u00e2n ph\u1ed1i kh\u00f4ng th\u1ec3 hi\u1ec7n, v\u00e0 th\u01b0\u1eddng \u0111\u01b0\u1ee3c ghi r\u00f5 b\u1eb1ng ch\u1eef nh\u1ecf trong b\u1ea3ng d\u1eef li\u1ec7u \u0111\u1ea7y \u0111\u1ee7, ch\u00ednh l\u00e0 ph\u01b0\u01a1ng ph\u00e1p \u0111o l\u01b0\u1eddng: d\u1ea3i t\u1ea7n (th\u01b0\u1eddng l\u00e0 20 MHz), \u0111i\u1ec1u ki\u1ec7n t\u1ea3i (th\u01b0\u1eddng l\u00e0 t\u1ea3i \u0111\u1ea7y \u0111\u1ee7), v\u00e0 ph\u01b0\u01a1ng ph\u00e1p k\u1ebft th\u00fac (k\u1ef9 thu\u1eadt c\u00e1p \u0111\u1ed3ng tr\u1ee5c 50 \u03a9 trong t\u00e0i li\u1ec7u h\u01b0\u1edbng d\u1eabn \u1ee9ng d\u1ee5ng c\u1ee7a Analog Devices, <a href=\"https:\/\/www.analog.com\/en\/resources\/app-notes\/an-1144.html\" target=\"_blank\" rel=\"noopener\">M\u1ed9t ngh\u00ecn m\u1ed9t tr\u0103m b\u1ed1n m\u01b0\u01a1i b\u1ed1n<\/a>). Hai b\u1ed9 ngu\u1ed3n \u0111\u1ec1u c\u00f3 th\u1ec3 kh\u1eb3ng \u0111\u1ecbnh m\u1ed9t c\u00e1ch ch\u00ednh x\u00e1c r\u1eb1ng ch\u00fang c\u00f3 \u201c120 mVp-p\u201d nh\u01b0ng l\u1ea1i ho\u1ea1t \u0111\u1ed9ng kh\u00e1c nhau khi ch\u1ecbu d\u00f2ng t\u1ea3i, b\u1edfi v\u00ec m\u1ed9t b\u1ed9 \u0111\u01b0\u1ee3c \u0111o \u1edf t\u1ea3i 50% c\u00f2n b\u1ed9 kia \u1edf t\u1ea3i 100%, ho\u1eb7c m\u1ed9t b\u1ed9 ho\u1ea1t \u0111\u1ed9ng \u1edf t\u1ea7n s\u1ed1 20 MHz c\u00f2n b\u1ed9 kia ho\u1ea1t \u0111\u1ed9ng \u1edf ch\u1ebf \u0111\u1ed9 m\u1edf r\u1ed9ng t\u1ed1i \u0111a.<\/p>\n\n \n <div class=\"bp-specnote-card\">\n <div class=\"bp-specnote-cells\">\n <div class=\"bp-specnote-cell\">\n <p class=\"bp-specnote-label\">typ<\/p>\n <p class=\"bp-specnote-text\">M\u1ed9t m\u1eabu th\u1eed th\u1eadt tuy\u1ec7t v\u1eddi v\u00e0o m\u1ed9t ng\u00e0y \u0111\u1eb9p tr\u1eddi.<\/p>\n <\/div>\n <div class=\"bp-specnote-cell\">\n <p class=\"bp-specnote-label\">v\u01b0\u1ee3t qu\u00e1<\/p>\n <p class=\"bp-specnote-text\">Cam k\u1ebft m\u00e0 b\u1ea1n c\u00f3 th\u1ec3 y\u00eau c\u1ea7u nh\u00e0 cung c\u1ea5p ph\u1ea3i tu\u00e2n th\u1ee7.<\/p>\n <\/div>\n <\/div>\n <p class=\"bp-specnote-foot\">Ch\u1ec9 in c\u00e1c gi\u00e1 tr\u1ecb \u0111i\u1ec3n h\u00ecnh th\u00f4i sao? Kh\u00f4ng c\u00f3 g\u00ec \u0111\u01b0\u1ee3c \u0111\u1ea3m b\u1ea3o c\u1ea3.<\/p>\n <\/div>\n\n <h3>\u0110i\u1ec3m kh\u00e1c bi\u1ec7t th\u1ef1c s\u1ef1 gi\u1eefa c\u00e1c m\u1eb7t h\u00e0ng gi\u00e1 r\u1ebb v\u00e0 cao c\u1ea5p<\/h3>\n\n <p>\u0110\u00e2y l\u00e0 xu h\u01b0\u1edbng \u0111\u00e1ng l\u01b0u \u00fd: v\u1ec1 \u0111\u1ed9 g\u1ee3n dao \u0111\u1ed9ng c\u01a1 b\u1ea3n, c\u00e1c b\u1ed9 ngu\u1ed3n gi\u00e1 r\u1ebb v\u00e0 th\u01b0\u01a1ng hi\u1ec7u n\u1ed5i ti\u1ebfng c\u00f9ng ph\u00e2n kh\u00fac \u0111\u1ec1u n\u1eb1m trong c\u00f9ng m\u1ed9t kho\u1ea3ng gi\u00e1 tr\u1ecb t\u00ednh b\u1eb1ng mili-v\u00f4n: m\u1ee9c 80 \u0111\u1ebfn 150 mVp-p tr\u00ean c\u00e1c \u0111\u01b0\u1eddng ngu\u1ed3n 12\u201348 V l\u00e0 ph\u1ed5 bi\u1ebfn tr\u00ean th\u1ecb tr\u01b0\u1eddng. S\u1ef1 ch\u00eanh l\u1ec7ch xu\u1ea5t hi\u1ec7n \u1edf ba t\u00edn hi\u1ec7u c\u00f2n l\u1ea1i. C\u00e1c \u0111\u1ec9nh nhi\u1ec5u kh\u00f4ng \u0111\u01b0\u1ee3c quy \u0111\u1ecbnh (ho\u1eb7c b\u1ecb lo\u1ea1i tr\u1eeb b\u1eb1ng c\u00e1c gi\u1edbi h\u1ea1n b\u0103ng th\u00f4ng); ph\u1ea3n \u1ee9ng qu\u00e1 \u0111\u1ed9 kh\u00f4ng n\u1eb1m trong h\u00e0ng dao \u0111\u1ed9ng; v\u00e0 t\u00ednh minh b\u1ea1ch v\u1ec1 \u0111i\u1ec1u ki\u1ec7n (li\u1ec7u nh\u00e0 cung c\u1ea5p c\u00f3 ti\u1ebft l\u1ed9 c\u00f4ng th\u1ee9c s\u1ea3n xu\u1ea5t hay kh\u00f4ng) r\u1ea5t \u0111a d\u1ea1ng. V\u00ec v\u1eady, khi s\u1ef1 ch\u00eanh l\u1ec7ch gi\u00e1 mang l\u1ea1i gi\u00e1 tr\u1ecb th\u1ef1c s\u1ef1, \u0111\u00f3 th\u01b0\u1eddng l\u00e0 s\u1ef1 kh\u00e1c bi\u1ec7t gi\u1eefa ti\u00eau chu\u1ea9n \"t\u1ed1i \u0111a\" v\u00e0 \"\u0111i\u1ec3n h\u00ecnh\", t\u00ednh nh\u1ea5t qu\u00e1n gi\u1eefa c\u00e1c l\u00f4 h\u00e0ng, \u0111i\u1ec1u ki\u1ec7n th\u1eed nghi\u1ec7m trung th\u1ef1c, v\u00e0 ch\u1ebf \u0111\u1ed9 b\u1ea3o h\u00e0nh \u0111i k\u00e8m v\u1edbi con s\u1ed1 \u0111\u00f3, ch\u1ee9 kh\u00f4ng ph\u1ea3i l\u00e0 con s\u1ed1 dao \u0111\u1ed9ng th\u1ea5p h\u01a1n.<\/p>\n\n <h3>N\u0103m c\u00e2u h\u1ecfi c\u1ea7n \u0111\u1eb7t ra cho b\u1ea5t k\u1ef3 nh\u00e0 cung c\u1ea5p b\u1ed9 ngu\u1ed3n n\u00e0o<\/h3>\n\n \n <div class=\"rich-checklist\">\n <p class=\"rich-checklist-title\"><span class=\"rich-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"m3 17 2 2 4-4\"\/><path d=\"m3 7 2 2 4-4\"\/><path d=\"M13 6h8\"\/><path d=\"M13 12h8\"\/><path d=\"M13 18h8\"\/><\/svg><\/span>N\u0103m c\u00e2u h\u1ecfi c\u1ea7n l\u01b0u \u00fd tr\u01b0\u1edbc khi so s\u00e1nh c\u00e1c th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u1ee7a Ripple<\/p>\n <ul class=\"rich-checklist-list\">\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>\u0110\u00e2y l\u00e0 typ hay max?<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>N\u00f3 \u0111\u01b0\u1ee3c \u0111o \u1edf b\u0103ng th\u00f4ng n\u00e0o (20 MHz hay b\u0103ng th\u00f4ng m\u1edf)?<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>\u1ede m\u1ee9c t\u1ea3i n\u00e0o (\u0111\u1ea7y, m\u1ed9t n\u1eeda hay kh\u00f4ng x\u00e1c \u0111\u1ecbnh)?<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>C\u00f3 ti\u00eau chu\u1ea9n ri\u00eang v\u1ec1 nhi\u1ec5u kh\u00f4ng, hay \u201c\u0111\u1ed9 dao \u0111\u1ed9ng v\u00e0 nhi\u1ec5u\u201d \u0111\u01b0\u1ee3c g\u1ed9p chung l\u1ea1i v\u1edbi nhau?<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>Khi t\u1ea3i th\u1ef1c t\u1ebf thay \u0111\u1ed5i theo t\u1eebng b\u01b0\u1edbc th\u00ec t\u00edn hi\u1ec7u \u0111\u1ea7u ra s\u1ebd nh\u01b0 th\u1ebf n\u00e0o, v\u00e0 c\u00f3 th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt v\u1ec1 hi\u1ec7n t\u01b0\u1ee3ng qu\u00e1 \u0111\u1ed9 kh\u00f4ng?<\/li>\n <\/ul>\n <\/div>\n\n <p>V\u00e0 ranh gi\u1edbi m\u00e0 ch\u1eb3ng ai in ra: <strong>khi vi\u1ec7c l\u1ecdc d\u1eef li\u1ec7u kh\u00f4ng th\u1ec3 kh\u1eafc ph\u1ee5c \u0111\u01b0\u1ee3c v\u1ea5n \u0111\u1ec1.<\/strong> N\u1ebfu b\u1ea1n \u0111\u00e3 th\u1eed s\u1eed d\u1ee5ng t\u1ee5 \u0111i\u1ec7n \u0111\u1ea7u ra m\u00e0 m\u1ee9c \u201cripple\u201d v\u1eabn cao, th\u00ec g\u1ea7n nh\u01b0 ch\u1eafc ch\u1eafn l\u00e0 b\u1ea1n \u0111ang x\u1eed l\u00fd c\u00e1c \u0111\u1ec9nh nhi\u1ec5u, ch\u1ee9 kh\u00f4ng ph\u1ea3i ripple. C\u00e1c t\u1ee5 \u0111i\u1ec7n \u1edf \u0111\u1ea7u ra c\u00f3 th\u1ec3 l\u00e0m m\u1ecbn th\u00e0nh ph\u1ea7n \u0111\u1ecbnh k\u1ef3 nh\u01b0ng s\u1ebd kh\u00f4ng lo\u1ea1i b\u1ecf \u0111\u01b0\u1ee3c c\u00e1c \u0111\u1ec9nh nhi\u1ec5u c\u00f3 d\u1ea3i t\u1ea7n tr\u00f9ng l\u1eb7p v\u1edbi t\u00edn hi\u1ec7u chuy\u1ec3n m\u1ea1ch (<a href=\"https:\/\/electronics.stackexchange.com\/questions\/707711\/switching-power-supply-has-high-ripple-voltage-no-matter-how-many-capacitors-are\" target=\"_blank\" rel=\"noopener\">StackExchange v\u1ec1 \u0110i\u1ec7n t\u1eed<\/a>, 2024). \u0110\u1ed1i v\u1edbi c\u00e1c t\u1ea3i y\u00eau c\u1ea7u \u0111\u1ed9 ch\u00ednh x\u00e1c cao, c\u00e2u tr\u1ea3 l\u1eddi trung th\u1ef1c th\u01b0\u1eddng l\u00e0 s\u1eed d\u1ee5ng b\u1ed9 \u0111i\u1ec1u ch\u1ec9nh sau (m\u1ed9t b\u1ed9 l\u1ecdc LC ho\u1eb7c b\u1ed9 \u0111i\u1ec1u ch\u1ec9nh \u0111i\u1ec7n \u00e1p tuy\u1ebfn t\u00ednh LDO \u0111\u1eb7t sau b\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch) thay v\u00ec m\u1ed9t b\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch \u0111\u1eaft ti\u1ec1n h\u01a1n v\u1edbi th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt \u1ea5n t\u01b0\u1ee3ng h\u01a1n.<\/p>\n\n <h2>Kh\u1eafc ph\u1ee5c s\u1ef1 c\u1ed1 t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng: Ngu\u1ed3n 24 V \u201cb\u1ecb nhi\u1ec5u\u201d \u0111\u00e3 l\u00e0m h\u1ecfng c\u1ea3m bi\u1ebfn c\u1ee7a t\u00f4i \u2014 \u0110\u00f3 c\u00f3 ph\u1ea3i l\u00e0 hi\u1ec7n t\u01b0\u1ee3ng g\u1ee3n s\u00f3ng hay kh\u00f4ng?<\/h2>\n\n <p>Khi m\u1ed9t b\u1ed9 truy\u1ec1n t\u00edn hi\u1ec7u 4\u201320 mA li\u00ean t\u1ee5c b\u1ecb ch\u00e1y ho\u1eb7c gi\u00e1 tr\u1ecb \u0111o analog b\u1ecb l\u1ec7ch, ph\u1ea3n \u1ee9ng b\u1ea3n n\u0103ng c\u1ee7a ng\u01b0\u1eddi l\u00e0m vi\u1ec7c t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng l\u00e0 ho\u00e0n to\u00e0n \u0111\u00fang: h\u00e3y nghi ng\u1edd ngu\u1ed3n \u0111i\u1ec7n tr\u01b0\u1edbc ti\u00ean. \u201c\u0110i\u1ec1u \u0111\u1ea7u ti\u00ean t\u00f4i s\u1ebd ki\u1ec3m tra l\u00e0 ngu\u1ed3n \u0111i\u1ec7n \u2014 \u0111\u1ea3m b\u1ea3o \u0111\u00f3 l\u00e0 ngu\u1ed3n 24 VDC s\u1ea1ch v\u00e0 \u1ed5n \u0111\u1ecbnh, kh\u00f4ng c\u00f3 \u0111\u1ed9t bi\u1ebfn hay nhi\u1ec5u; ngu\u1ed3n \u0111i\u1ec7n kh\u00f4ng \u1ed5n \u0111\u1ecbnh c\u00f3 th\u1ec3 l\u00e0m h\u1ecfng c\u1ea3m bi\u1ebfn r\u1ea5t nhanh,\u201d nh\u01b0 m\u1ed9t k\u1ef9 thu\u1eadt vi\u00ean tr\u00ean di\u1ec5n \u0111\u00e0n r\/PLC \u0111\u00e3 chia s\u1ebb khi ch\u1ea9n \u0111o\u00e1n m\u1ed9t b\u1ed9 truy\u1ec1n t\u00edn hi\u1ec7u \u00e1p su\u1ea5t \u0111\u00e3 l\u00e0m h\u1ecfng hai b\u1ed9 thay th\u1ebf ch\u1ec9 trong v\u00e0i ng\u00e0y (<a href=\"https:\/\/www.reddit.com\/r\/PLC\/comments\/1kragst\/420_ma_pressure_transmitter_help\/\" target=\"_blank\" rel=\"noopener\">Reddit r\/PLC<\/a>, 2025). Nh\u01b0ng h\u00e3y l\u01b0u \u00fd nh\u1eefng y\u1ebfu t\u1ed1 m\u00e0 danh s\u00e1ch ki\u1ec3m tra trong ch\u1ee7 \u0111\u1ec1 \u0111\u00f3 th\u1ef1c s\u1ef1 nh\u1eafm \u0111\u1ebfn: c\u00e1c \u0111\u1ec9nh \u0111i\u1ec7n \u00e1p khi c\u00f4ng t\u1eafc t\u01a1 v\u00e0 \u0111\u1ed9ng c\u01a1 kh\u1edfi \u0111\u1ed9ng, n\u1ed1i \u0111\u1ea5t v\u00e0 li\u00ean k\u1ebft, r\u00f2 r\u1ec9 t\u1eeb b\u1ed9 bi\u1ebfn t\u1ea7n (VFD), ch\u1ee9 kh\u00f4ng ph\u1ea3i th\u00f4ng s\u1ed1 g\u1ee3n s\u00f3ng. \u0110\u00f3 ch\u00ednh l\u00e0 s\u1ef1 ph\u00e2n bi\u1ec7t b\u1ed1n t\u00edn hi\u1ec7u \u0111ang \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng trong th\u1ef1c t\u1ebf.<\/p>\n\n <ol>\n <li><strong>X\u00e1c \u0111\u1ecbnh ph\u1ea1m vi c\u1ee7a \u0111\u01b0\u1eddng ray qua c\u00e1c s\u1ef1 ki\u1ec7n chuy\u1ec3n m\u1ea1ch:<\/strong> H\u00e3y xem x\u00e9t nh\u1eefng g\u00ec x\u1ea3y ra ngay l\u1eadp t\u1ee9c khi m\u1ed9t r\u01a1le ho\u1eb7c \u0111\u1ed9ng c\u01a1 trong t\u1ee7 \u0111i\u1ec7n ho\u1ea1t \u0111\u1ed9ng, ch\u1ee9 kh\u00f4ng ch\u1ec9 d\u1ef1a v\u00e0o d\u1ea1ng s\u00f3ng \u1ed5n \u0111\u1ecbnh.<\/li>\n <li><strong>Ki\u1ec3m tra \u0111i\u1ec7n \u00e1p tham chi\u1ebfu 0 V:<\/strong> Li\u1ec7u c\u1ef1c \u00e2m c\u1ee7a ngu\u1ed3n c\u00f3 \u0111\u01b0\u1ee3c n\u1ed1i v\u1edbi m\u1ed9t \u0111i\u1ec3m n\u1ed1i \u0111\u1ea5t \u0111ang d\u1eabn d\u00f2ng \u0111i\u1ec7n t\u1eeb c\u00e1c thi\u1ebft b\u1ecb kh\u00e1c kh\u00f4ng? Gi\u00e1 tr\u1ecb \u201c0 V\u201d thay \u0111\u1ed5i khi c\u00f3 t\u1ea3i l\u00e0 do v\u1ea5n \u0111\u1ec1 ti\u00eam d\u00f2ng, ch\u1ee9 kh\u00f4ng ph\u1ea3i do v\u1ea5n \u0111\u1ec1 dao \u0111\u1ed9ng.<\/li>\n <li><strong>H\u00e3y ch\u00fa \u00fd \u0111\u1ebfn c\u00e1c ngu\u1ed3n b\u00ean ngo\u00e0i:<\/strong> \u0110\u1ed9ng c\u01a1 \u0111i\u1ec1u khi\u1ec3n b\u1eb1ng bi\u1ebfn t\u1ea7n (VFD), ho\u1ea1t \u0111\u1ed9ng h\u00e0n g\u1ea7n \u0111\u00f3, \u0111i\u1ec3m n\u1ed1i \u0111\u1ea5t b\u1ecb \u0103n m\u00f2n tr\u00ean d\u00e2y chuy\u1ec1n s\u1ea3n xu\u1ea5t. M\u1ed9t tr\u01b0\u1eddng h\u1ee3p li\u00ean quan \u0111\u1ebfn r\/PLC \u0111\u00e3 x\u00e1c \u0111\u1ecbnh nguy\u00ean nh\u00e2n khi\u1ebfn c\u00e1c c\u1ea3m bi\u1ebfn li\u00ean t\u1ee5c h\u1ecfng l\u00e0 do \u0111i\u1ec3m n\u1ed1i \u0111\u1ea5t b\u1ecb \u0103n m\u00f2n tr\u00ean \u0111\u1ed9ng c\u01a1 b\u01a1m \u0111i\u1ec1u khi\u1ec3n b\u1eb1ng bi\u1ebfn t\u1ea7n (VFD), v\u1ed1n \u0111\u01b0\u1ee3c k\u1ebft n\u1ed1i v\u1eadt l\u00fd v\u1edbi c\u00f9ng m\u1ed9t b\u1ec3 ch\u1ee9a (<a href=\"https:\/\/www.reddit.com\/r\/PLC\/comments\/1kragst\/420_ma_pressure_transmitter_help\/\" target=\"_blank\" rel=\"noopener\">Reddit r\/PLC<\/a>, 2025).<\/li>\n <li><strong>Ti\u1ebfn h\u00e0nh th\u00ed nghi\u1ec7m c\u00e1ch ly:<\/strong> C\u1ea5p ngu\u1ed3n cho c\u1ea3m bi\u1ebfn nghi ng\u1edd t\u1eeb m\u1ed9t ngu\u1ed3n \u0111i\u1ec7n ri\u00eang bi\u1ec7t, d\u00e0nh ri\u00eang cho m\u1ee5c \u0111\u00edch n\u00e0y (ho\u1eb7c th\u00f4ng qua b\u1ed9 c\u00e1ch ly t\u00edn hi\u1ec7u). N\u1ebfu c\u1ea3m bi\u1ebfn v\u1eabn ho\u1ea1t \u0111\u1ed9ng b\u00ecnh th\u01b0\u1eddng \u1edf \u0111\u00f3, th\u00ec ngu\u1ed3n \u0111i\u1ec7n kh\u00f4ng ph\u1ea3i l\u00e0 nguy\u00ean nh\u00e2n g\u00e2y ra s\u1ef1 c\u1ed1; n\u1ebfu c\u1ea3m bi\u1ebfn c\u0169ng ng\u1eebng ho\u1ea1t \u0111\u1ed9ng \u1edf \u0111\u00f3, h\u00e3y ki\u1ec3m tra c\u1ea3m bi\u1ebfn v\u00e0 m\u1ea1ch \u0111i\u1ec1u khi\u1ec3n.<\/li>\n <\/ol>\n\n \n <div class=\"rich-steps\">\n <p class=\"rich-steps-title\"><span class=\"rich-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><circle cx=\"6\" cy=\"19\" r=\"3\"\/><path d=\"M9 19h8.5a3.5 3.5 0 0 0 0-7h-11a3.5 3.5 0 0 1 0-7H15\"\/><circle cx=\"18\" cy=\"5\" r=\"3\"\/><\/svg><\/span>Ph\u00e2n lo\u1ea1i t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng: c\u00f3 hi\u1ec7n t\u01b0\u1ee3ng g\u1ee3n s\u00f3ng hay kh\u00f4ng?<\/p>\n <ol class=\"rich-steps-list\">\n <li><span class=\"rich-step-num\">1<\/span>Xem x\u00e9t trong to\u00e0n b\u1ed9 qu\u00e1 tr\u00ecnh chuy\u1ec3n m\u1ea1ch, kh\u00f4ng ch\u1ec9 \u1edf tr\u1ea1ng th\u00e1i \u1ed5n \u0111\u1ecbnh<\/li>\n <li><span class=\"rich-step-num\">2<\/span>Ki\u1ec3m tra xem \u0111i\u1ec7n \u00e1p tham chi\u1ebfu 0 V c\u00f3 b\u1ecb dao \u0111\u1ed9ng theo c\u00e1c t\u1ea3i kh\u00e1c hay kh\u00f4ng<\/li>\n <li><span class=\"rich-step-num\">3<\/span>T\u00ecm ki\u1ebfm c\u00e1c ngu\u1ed3n g\u00e2y r\u00f2 r\u1ec9 b\u00ean ngo\u00e0i (bi\u1ebfn t\u1ea7n, m\u1ed1i h\u00e0n, c\u00e1c \u0111i\u1ec3m n\u1ed1i b\u1ecb \u0103n m\u00f2n)<\/li>\n <li><span class=\"rich-step-num\">4<\/span>H\u00e3y t\u00e1ch ri\u00eang c\u1ea3m bi\u1ebfn ra kh\u1ecfi ngu\u1ed3n \u0111i\u1ec7n chuy\u00ean d\u1ee5ng v\u00e0 theo d\u00f5i<\/li>\n <\/ol>\n <\/div>\n\n <p>Ng\u01b0\u1ee3c l\u1ea1i, ranh gi\u1edbi n\u00e0y c\u0169ng c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c hi\u1ec3u theo h\u01b0\u1edbng kh\u00e1c: r\u1ea5t nhi\u1ec1u c\u1ea3m bi\u1ebfn h\u1ecfng ho\u00e0n to\u00e0n kh\u00f4ng li\u00ean quan \u0111\u1ebfn b\u1ed9 ngu\u1ed3n. C\u00e1c v\u00f2ng l\u1eb7p \u0111\u1ea5t, hi\u1ec7n t\u01b0\u1ee3ng r\u00f2 r\u1ec9 ch\u1ebf \u0111\u1ed9 chung c\u1ee7a bi\u1ebfn t\u1ea7n (VFD), vi\u1ec7c h\u00e0n trong khi h\u1ec7 th\u1ed1ng \u0111ang t\u1eaft m\u00e1y, v\u00e0 ch\u00ednh c\u1ea3m bi\u1ebfn \u0111\u00f3 \u0111\u1ec1u ng\u1ee5y trang d\u01b0\u1edbi d\u1ea1ng \u201cngu\u1ed3n \u0111i\u1ec7n b\u1ea9n\u201d. B\u1ed1n b\u01b0\u1edbc n\u00e0y t\u1ed3n t\u1ea1i ch\u00ednh x\u00e1c \u0111\u1ec3 ng\u0103n b\u1ea1n thay th\u1ebf m\u1ed9t b\u1ed9 ngu\u1ed3n c\u00f2n t\u1ed1t b\u1eb1ng m\u1ed9t b\u1ed9 ngu\u1ed3n t\u1ed1t h\u01a1n r\u1ed3i cho r\u1eb1ng c\u00f4ng vi\u1ec7c \u0111\u00e3 ho\u00e0n t\u1ea5t. \u0110\u00f3 ch\u00ednh l\u00e0 tr\u01b0\u1eddng h\u1ee3p \u0111i\u1ec3n h\u00ecnh c\u1ee7a vi\u1ec7c \u201cs\u1eeda ch\u1eefa\u201d t\u1ed1n k\u00e9m nh\u01b0ng kh\u00f4ng gi\u1ea3i quy\u1ebft \u0111\u01b0\u1ee3c v\u1ea5n \u0111\u1ec1.<\/p>\n\n <h2>D\u00e0nh cho c\u00e1c nh\u00e0 ph\u00e2n ph\u1ed1i: H\u00e3y b\u00e1n d\u1ecbch v\u1ee5 ch\u1ea9n \u0111o\u00e1n, ch\u1ee9 kh\u00f4ng ph\u1ea3i m\u1ee9c \u0111i\u1ec7n \u00e1p millivolt th\u1ea5p nh\u1ea5t<\/h2>\n\n <p>N\u1ebfu b\u1ea1n kinh doanh b\u1ed9 ngu\u1ed3n, t\u1ea5t c\u1ea3 nh\u1eefng \u0111i\u1ec1u n\u00eau tr\u00ean \u0111\u1ec1u c\u00f3 th\u1ec3 t\u00f3m g\u1ecdn th\u00e0nh m\u1ed9t th\u1ef1c t\u1ebf th\u01b0\u01a1ng m\u1ea1i: kh\u00e1ch h\u00e0ng g\u1ecdi \u0111i\u1ec7n than phi\u1ec1n v\u1ec1 c\u1ea3m bi\u1ebfn b\u1ecb ch\u00e1y ho\u1eb7c v\u00f2ng \u0111i\u1ec1u khi\u1ec3n b\u1ecb l\u1ec7ch kh\u00f4ng ph\u1ea3i \u0111ang h\u1ecfi b\u1ed9 ngu\u1ed3n n\u00e0o c\u00f3 ch\u1ec9 s\u1ed1 g\u1ee3n s\u00f3ng th\u1ea5p nh\u1ea5t. H\u1ecd \u0111ang h\u1ecfi li\u1ec7u b\u1ed9 ngu\u1ed3n h\u1ecd \u0111ang d\u00f9ng c\u00f3 ph\u1ea3i l\u00e0 nguy\u00ean nh\u00e2n g\u00e2y ra s\u1ef1 c\u1ed1 hay kh\u00f4ng, v\u00e0 n\u00ean mua s\u1ea3n ph\u1ea9m n\u00e0o thay th\u1ebf. C\u00e1c linh ki\u1ec7n m\u00e0 b\u1ea1n b\u00e1n li\u00ean quan \u0111\u1ebfn c\u1ea3 hai kh\u00eda c\u1ea1nh c\u1ee7a c\u00e2u h\u1ecfi \u0111\u00f3.<\/p>\n\n <p>V\u00ec v\u1eady, logic b\u00e1n h\u00e0ng ph\u1ea3i tu\u00e2n theo logic k\u1ef9 thu\u1eadt. \u0110\u1ed1i v\u1edbi c\u00e1c t\u1ea3i thu\u1ed9c lo\u1ea1i mi\u1ec5n nhi\u1ec5m (r\u01a1le, \u0111\u00e8n, t\u1ee7 ti\u1ebfp \u0111i\u1ec3m \u2013 chi\u1ebfm ph\u1ea7n l\u1edbn th\u1ecb tr\u01b0\u1eddng s\u1eeda ch\u1eefa v\u00e0 b\u1ea3o tr\u00ec), \u0111\u1ed9 g\u1ee3n kh\u00f4ng ph\u1ea3i l\u00e0 \u0111i\u1ec3m b\u00e1n h\u00e0ng. H\u00e3y c\u1ea1nh tranh v\u1ec1 gi\u00e1 c\u1ea3, t\u00ednh s\u1eb5n c\u00f3 v\u00e0 \u0111\u1ed9 b\u1ec1n, v\u00e0 \u0111\u1eebng l\u00e3ng ph\u00ed c\u00e1c b\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt ch\u1ea5t l\u01b0\u1ee3ng cao cho nh\u1eefng kh\u00e1ch h\u00e0ng s\u1ebd kh\u00f4ng bao gi\u1edd nh\u1eadn ra s\u1ef1 kh\u00e1c bi\u1ec7t. \u0110\u1ed1i v\u1edbi c\u00e1c t\u1ea3i nh\u1ea1y c\u1ea3m (v\u00f2ng l\u1eb7p 4\u201320 mA, b\u1ed9 truy\u1ec1n t\u00edn hi\u1ec7u, th\u1ebb analog, b\u1ed9 m\u00e3 h\u00f3a), h\u00e3y b\u00e1n s\u1ef1 minh b\u1ea1ch v\u1ec1 th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt thay v\u00ec gi\u00e1 tr\u1ecb millivolt th\u1ea5p nh\u1ea5t. Cung c\u1ea5p gi\u00e1 tr\u1ecb t\u1ed1i \u0111a (ch\u1ee9 kh\u00f4ng ph\u1ea3i gi\u00e1 tr\u1ecb \u0111i\u1ec3n h\u00ecnh), b\u0103ng th\u00f4ng \u0111\u01b0\u1ee3c \u0111o v\u00e0 \u0111i\u1ec1u ki\u1ec7n t\u1ea3i; gi\u1ea3i th\u00edch nh\u1eefng g\u00ec con s\u1ed1 \u0111\u00f3 kh\u00f4ng bao g\u1ed3m (nhi\u1ec5u, hi\u1ec7n t\u01b0\u1ee3ng qu\u00e1 \u0111\u1ed9). \u0110\u00f3 l\u00e0 s\u1ef1 kh\u00e1c bi\u1ec7t gi\u1eefa m\u1ed9t giao d\u1ecbch h\u00e0ng h\u00f3a th\u00f4ng th\u01b0\u1eddng v\u00e0 m\u1ed9t giao d\u1ecbch t\u01b0 v\u1ea5n, v\u00e0 \u0111\u00f3 l\u00e0 ph\u1ea7n c\u1ee7a cu\u1ed9c tr\u00f2 chuy\u1ec7n m\u00e0 gi\u00e1 ni\u00eam y\u1ebft trong danh m\u1ee5c kh\u00f4ng th\u1ec3 l\u00e0m lu m\u1edd.<\/p>\n\n <p>C\u00f9ng m\u1ed9t logic n\u00e0y c\u0169ng gi\u00fap b\u1ea3o v\u1ec7 d\u1ecbch v\u1ee5 h\u1eadu m\u00e3i c\u1ee7a b\u1ea1n: khi kh\u00e1ch h\u00e0ng b\u00e1o c\u00e1o s\u1ef1 c\u1ed1, h\u00e3y ti\u1ebfn h\u00e0nh ki\u1ec3m tra s\u01a1 b\u1ed9 t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng tr\u01b0\u1edbc khi \u0111\u1ec1 xu\u1ea5t cung c\u1ea5p thi\u1ebft b\u1ecb thay th\u1ebf. M\u1ed9t c\u1ea3m bi\u1ebfn b\u1ecb h\u1ecfng do c\u00e1c \u0111\u1ee3t t\u0103ng \u00e1p \u0111\u1ed9t ng\u1ed9t v\u00e0 hi\u1ec7n t\u01b0\u1ee3ng qu\u00e1 \u00e1p t\u1ea1m th\u1eddi s\u1ebd khi\u1ebfn thi\u1ebft b\u1ecb thay th\u1ebf c\u0169ng b\u1ecb h\u1ecfng theo. C\u00e2u tr\u1ea3 l\u1eddi trung th\u1ef1c ki\u1ec3u \u201cv\u1ea5n \u0111\u1ec1 kh\u00f4ng n\u1eb1m \u1edf b\u1ed9 ngu\u1ed3n, \u0111\u00e2y l\u00e0 nh\u1eefng g\u00ec c\u1ea7n ki\u1ec3m tra\u201d ch\u00ednh l\u00e0 \u0111i\u1ec1u khi\u1ebfn kh\u00e1ch h\u00e0ng mu\u1ed1n li\u00ean h\u1ec7 l\u1ea1i v\u1edbi nh\u00e0 ph\u00e2n ph\u1ed1i. V\u00e0 h\u00e3y nh\u1edb r\u1eb1ng to\u00e0n b\u1ed9 chu\u1ed7i thi\u1ebft b\u1ecb \u0111\u1ec1u n\u1eb1m tr\u00ean c\u00f9ng m\u1ed9t k\u1ec7: b\u1ed9 ngu\u1ed3n, c\u1ea3m bi\u1ebfn v\u00e0 r\u01a1le \u0111i\u1ec1u khi\u1ec3n t\u1ea3i \u0111\u1ec1u thu\u1ed9c c\u00f9ng m\u1ed9t \u0111\u01a1n h\u00e0ng, c\u00f9ng m\u1ed9t t\u1ee7 thi\u1ebft b\u1ecb, v\u00e0 th\u01b0\u1eddng c\u00f3 c\u00f9ng m\u1ed9t ch\u1ea9n \u0111o\u00e1n.<\/p>\n\n \n <div class=\"bp-takeaway-card\">\n <p class=\"bp-takeaway-title\"><span class=\"bp-takeaway-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><circle cx=\"12\" cy=\"12\" r=\"10\"\/><circle cx=\"12\" cy=\"12\" r=\"6\"\/><circle cx=\"12\" cy=\"12\" r=\"2\"\/><\/svg><\/span>Ba quy t\u1eafc<\/p>\n <div class=\"bp-takeaway-rows\">\n <div class=\"bp-takeaway-row\"><span class=\"bp-takeaway-num\">1<\/span><p class=\"bp-takeaway-text\">C\u00e1c y\u1ebfu t\u1ed1 \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn h\u1ec7 mi\u1ec5n d\u1ecbch: gi\u00e1 b\u00e1n, \u0111\u1ed9 b\u1ec1n, t\u00ednh s\u1eb5n c\u00f3.<\/p><\/div>\n <div class=\"bp-takeaway-row\"><span class=\"bp-takeaway-num\">2<\/span><p class=\"bp-takeaway-text\">T\u1ea3i nh\u1ea1y c\u1ea3m: cung c\u1ea5p th\u00f4ng tin v\u1ec1 gi\u00e1 tr\u1ecb t\u1ed1i \u0111a, b\u0103ng th\u00f4ng v\u00e0 c\u00e1c \u0111i\u1ec1u ki\u1ec7n t\u1ea3i.<\/p><\/div>\n <div class=\"bp-takeaway-row\"><span class=\"bp-takeaway-num\">3<\/span><p class=\"bp-takeaway-text\">S\u1ef1 c\u1ed1 t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng: \u01b0u ti\u00ean ki\u1ec3m tra s\u01a1 b\u1ed9 tr\u01b0\u1edbc, thay th\u1ebf sau.<\/p><\/div>\n <\/div>\n <\/div>\n\n <p><em>N\u1ebfu b\u1ea1n c\u1ea7n so s\u00e1nh c\u00e1c b\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch g\u1eafn tr\u00ean thanh DIN trong d\u1ea3i c\u00f4ng su\u1ea5t t\u1eeb 15 W \u0111\u1ebfn 480 W, ho\u1eb7c mu\u1ed1n c\u00f3 ng\u01b0\u1eddi c\u00f9ng b\u1ea1n xem x\u00e9t v\u00e0 l\u1ef1a ch\u1ecdn, OMCH\u2019s <a href=\"https:\/\/www.omch.com\/vi\/switch-mode-power-supply\/\" target=\"_blank\" rel=\"noopener\">D\u00f2ng s\u1ea3n ph\u1ea9m b\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch<\/a> v\u00e0 <a href=\"https:\/\/www.omch.com\/vi\/product-selection\/\" target=\"_blank\" rel=\"noopener\">h\u1ed7 tr\u1ee3 l\u1ef1a ch\u1ecdn s\u1ea3n ph\u1ea9m<\/a> l\u00e0 \u0111i\u1ec3m kh\u1edfi \u0111\u1ea7u thi\u1ebft th\u1ef1c.<\/em><\/p>\n\n \n <div class=\"bp-cta-end\">\n <p class=\"bp-cta-end-title\">C\u00f3 th\u1eafc m\u1eafc v\u1ec1 th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt? H\u00e3y h\u1ecfi tr\u01b0\u1edbc khi mua.<\/p>\n <p class=\"bp-cta-end-sub\">H\u00e3y g\u1eedi cho ch\u00fang t\u00f4i lo\u1ea1i t\u1ea3i v\u00e0 d\u00f2ng \u0111i\u1ec7n ti\u00eau th\u1ee5 c\u1ee7a \u1ee9ng d\u1ee5ng c\u1ee7a b\u1ea1n. C\u00e1c k\u1ef9 s\u01b0 t\u01b0 v\u1ea5n c\u1ee7a ch\u00fang t\u00f4i s\u1ebd \u0111\u1ec1 xu\u1ea5t b\u1ed9 ngu\u1ed3n g\u1eafn tr\u00ean thanh DIN ho\u1eb7c b\u1ed9 ngu\u1ed3n c\u00f3 v\u1ecf b\u1ecdc ph\u00f9 h\u1ee3p v\u00e0 cung c\u1ea5p cho b\u1ea1n c\u00e1c th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt ch\u00ednh x\u00e1c m\u00e0 b\u1ea1n c\u00f3 th\u1ec3 tin c\u1eady.<\/p>\n <a class=\"bp-cta-end-btn\" href=\"https:\/\/www.omch.com\/vi\/contact\/\" target=\"_self\">G\u1eedi y\u00eau c\u1ea7u t\u01b0 v\u1ea5n l\u1ef1a ch\u1ecdn<svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M5 12h14\"\/><path d=\"m12 5 7 7-7 7\"\/><\/svg><\/a>\n <\/div>\n\n <p class=\"bd-refs-title\">T\u00e0i li\u1ec7u tham kh\u1ea3o<\/p>\n <ol class=\"bd-refs\">\n <li>Wikipedia. \u201cRipple (\u0111i\u1ec7n).\u201d <a href=\"https:\/\/en.wikipedia.org\/wiki\/Ripple_(electrical)\" target=\"_blank\" rel=\"noopener\">https:\/\/en.wikipedia.org\/wiki\/Ripple_(electrical)<\/a><\/li>\n <li>Analog Devices. \u201cAN-1144: \u0110o dao \u0111\u1ed9ng \u0111\u1ea7u ra v\u00e0 hi\u1ec7n t\u01b0\u1ee3ng chuy\u1ec3n m\u1ea1ch t\u1ea1m th\u1eddi trong b\u1ed9 \u0111i\u1ec1u ch\u1ec9nh chuy\u1ec3n m\u1ea1ch.\u201d <a href=\"https:\/\/www.analog.com\/en\/resources\/app-notes\/an-1144.html\" target=\"_blank\" rel=\"noopener\">https:\/\/www.analog.com\/en\/resources\/app-notes\/an-1144.html<\/a><\/li>\n <li>Tom\u2019s Hardware. \u201c\u0110i\u1ec7n \u00e1p dao \u0111\u1ed9ng \u2014 C\u00e1ch ch\u00fang t\u00f4i ki\u1ec3m tra c\u00e1c b\u1ed9 ngu\u1ed3n.\u201d <a href=\"https:\/\/www.tomshardware.com\/reviews\/how-we-test-psu,4042-5.html\" target=\"_blank\" rel=\"noopener\">https:\/\/www.tomshardware.com\/reviews\/how-we-test-psu,4042-5.html<\/a><\/li>\n <li>Di\u1ec5n \u0111\u00e0n EEVblog. \u201c\u0110o dao \u0111\u1ed9ng ngu\u1ed3n b\u1eb1ng k\u1ef9 thu\u1eadt n\u00e0y.\u201d <a href=\"https:\/\/www.eevblog.com\/forum\/beginners\/measure-power-supply-ripple-with-this-technique\/\" target=\"_blank\" rel=\"noopener\">https:\/\/www.eevblog.com\/forum\/beginners\/measure-power-supply-ripple-with-this-technique\/<\/a><\/li>\n <li>Electronics StackExchange. \u201cB\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch c\u00f3 \u0111i\u1ec7n \u00e1p dao \u0111\u1ed9ng cao b\u1ea5t k\u1ec3 th\u00eam bao nhi\u00eau t\u1ee5 \u0111i\u1ec7n. \u201d <a href=\"https:\/\/electronics.stackexchange.com\/questions\/707711\/\" target=\"_blank\" rel=\"noopener\">https:\/\/electronics.stackexchange.com\/questions\/707711\/<\/a><\/li>\n <li>Electronics StackExchange. \u201cC\u00e1c y\u1ebfu t\u1ed1 c\u1ea7n xem x\u00e9t v\u1ec1 dao \u0111\u1ed9ng \u0111i\u1ec7n \u00e1p \u0111\u1ea7u ra.\u201d <a href=\"https:\/\/electronics.stackexchange.com\/questions\/501187\/\" target=\"_blank\" rel=\"noopener\">https:\/\/electronics.stackexchange.com\/questions\/501187\/<\/a><\/li>\n <li>Reddit r\/PLC. \u201cH\u1ed7 tr\u1ee3 v\u1ec1 b\u1ed9 truy\u1ec1n \u00e1p su\u1ea5t 4\u201320 mA.\u201d <a href=\"https:\/\/www.reddit.com\/r\/PLC\/comments\/1kragst\/420_ma_pressure_transmitter_help\/\" target=\"_blank\" rel=\"noopener\">https:\/\/www.reddit.com\/r\/PLC\/comments\/1kragst\/420_ma_pressure_transmitter_help\/<\/a><\/li>\n <li>Reddit r\/AskElectronics. \u201cM\u1ee9c nhi\u1ec5u\/dao \u0111\u1ed9ng n\u00e0o \u0111\u01b0\u1ee3c ch\u1ea5p nh\u1eadn tr\u00ean c\u00e1c b\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch gi\u00e1 r\u1ebb?\u201d <a href=\"https:\/\/www.reddit.com\/r\/AskElectronics\/comments\/1gm8h7m\/\" target=\"_blank\" rel=\"noopener\">https:\/\/www.reddit.com\/r\/AskElectronics\/comments\/1gm8h7m\/<\/a><\/li>\n <li>WSJT-X Groups.io. \u201cM\u1ee9c dao \u0111\u1ed9ng \u0111i\u1ec7n \u00e1p ngu\u1ed3n PA n\u00e0o \u0111\u01b0\u1ee3c ch\u1ea5p nh\u1eadn?\u201d <a href=\"https:\/\/wsjtx.groups.io\/g\/main\/topic\/acceptable_pa_power_supply\/71775932\" target=\"_blank\" rel=\"noopener\">https:\/\/wsjtx.groups.io\/g\/main\/topic\/acceptable_pa_power_supply\/71775932<\/a><\/li>\n <li>OMCH. \u201cB\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch.\u201d <a href=\"https:\/\/www.omch.com\/vi\/switch-mode-power-supply\/\" target=\"_blank\" rel=\"noopener\">https:\/\/www.omch.com\/switch-mode-power-supply\/<\/a><\/li>\n <li>OMCH. \u201cL\u1ef1a ch\u1ecdn s\u1ea3n ph\u1ea9m.\u201d <a href=\"https:\/\/www.omch.com\/vi\/product-selection\/\" target=\"_blank\" rel=\"noopener\">https:\/\/www.omch.com\/product-selection\/<\/a><\/li>\n <li>OMCH. Trang ch\u1ee7. <a href=\"https:\/\/www.omch.com\/vi\/\" target=\"_blank\" rel=\"noopener\">https:\/\/www.omch.com\/<\/a><\/li>\n <\/ol>\n <\/article>\n<\/div>\n\n<\/body><\/html>","protected":false},"excerpt":{"rendered":"<p>Dao \u0111\u1ed9ng ngu\u1ed3n \u0111i\u1ec7n: N\u00f3 l\u00e0 g\u00ec, c\u00e1ch \u0111o l\u01b0\u1eddng v\u00e0 khi n\u00e0o n\u00f3 quan tr\u1ecdng B\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u1ee7a b\u1ed9 ngu\u1ed3n cho bi\u1ebft dao \u0111\u1ed9ng l\u00e0 \u201c\u2264100 mVp-p.\u201d B\u1ea1n k\u1ebft n\u1ed1i m\u00e1y hi\u1ec7n s\u00f3ng v\u1edbi \u0111\u1ea7u ra v\u00e0 th\u1ea5y d\u1ea1ng s\u00f3ng ho\u00e0n to\u00e0n kh\u00f4ng gi\u1ed1ng v\u1edbi s\u00f3ng r\u0103ng c\u01b0a 100 mV s\u1ea1ch, trong khi m\u1ed9t ng\u01b0\u1eddi \u0111am m\u00ea \u0111i\u1ec7n t\u1eed \u1edf ph\u00f2ng b\u00ean c\u1ea1nh v\u1eeba \u0111o \u0111\u01b0\u1ee3c 1,4 Vp-p \u1edf 5 [\u2026]<\/p>","protected":false},"author":4,"featured_media":12316,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_seopress_robots_primary_cat":"none","_seopress_titles_title":"Power Supply Ripple: What It Is & How to Measure It","_seopress_titles_desc":"Learn what power supply ripple is, how to measure ripple voltage correctly with an oscilloscope, and when ripple matters for different loads.","_seopress_robots_index":"","footnotes":""},"categories":[79],"tags":[],"class_list":["post-12313","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-mmlblog"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/posts\/12313","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/comments?post=12313"}],"version-history":[{"count":1,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/posts\/12313\/revisions"}],"predecessor-version":[{"id":12318,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/posts\/12313\/revisions\/12318"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/media\/12316"}],"wp:attachment":[{"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/media?parent=12313"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/categories?post=12313"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/tags?post=12313"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

{"id":12313,"date":"2026-09-11T06:36:01","date_gmt":"2026-09-11T06:36:01","guid":{"rendered":"https:\/\/www.omch.com\/?p=12313"},"modified":"2026-09-11T06:36:02","modified_gmt":"2026-09-11T06:36:02","slug":"power-supply-ripple","status":"publish","type":"post","link":"https:\/\/www.omch.com\/vi\/power-supply-ripple\/","title":{"rendered":"Dao \u0111\u1ed9ng ngu\u1ed3n: Kh\u00e1i ni\u1ec7m, c\u00e1ch \u0111o l\u01b0\u1eddng v\u00e0 khi n\u00e0o n\u00f3 quan tr\u1ecdng"},"content":{"rendered":"\n\n \n \n Dao \u0111\u1ed9ng ngu\u1ed3n: Kh\u00e1i ni\u1ec7m, c\u00e1ch \u0111o l\u01b0\u1eddng v\u00e0 khi n\u00e0o n\u00f3 quan tr\u1ecdng<\/title>\n<\/head>\n<body>\n\n<div class=\"bd-post\">\n <style>\n \/* fonts: BLOG scope only (brand Standard Blog CSS Header, verbatim). *\/\n @import url('https:\/\/fonts.googleapis.com\/css2?family=Manrope:wght@400;600;700&family=Roboto:wght@600;700&display=swap');\n\n .bd-post {\n \/* brand header system values + plan palette (single source of hex) *\/\n --prose-width: 760px;\n --gap-attach: 16px;\n --gap-normal: 32px;\n --gap-section: 48px;\n --pad-compact: 16px;\n --pad-standard: 24px;\n --body-bg: #FFFFFF;\n --text-primary: #333333;\n --text-secondary: #6E6E6E;\n --heading-ink: #000000;\n --accent: #479DE2;\n --accent-text: #2A76B4;\n --accent-on-tint: #1F5F9E;\n --accent-hover: #1F4E8C;\n --accent-hot: #FD9649;\n --inverse-bg: #1E1E1E;\n --inverse-text: #FFFFFF;\n --inverse-text-2: #B8B8B8;\n --card-fill: #E3F0FB;\n --card-border: #3F76AE;\n --card-secondary: #5F5F5F;\n --btn-white: #FFFFFF;\n --btn-ink: #0D3972;\n font-family: \"Manrope\", sans-serif;\n font-size: 16px;\n font-weight: 400;\n line-height: 1.6;\n color: var(--text-primary);\n background: var(--body-bg);\n padding: 40px;\n max-width: 100%;\n box-sizing: border-box;\n }\n .bd-post a { overflow-wrap: anywhere; word-break: break-word; }\n .bd-post p, .bd-post li { overflow-wrap: break-word; }\n .bd-post .bd-post-article { max-width: var(--prose-width); margin: 0 auto; }\n\n \/* anchor permit-list: visual props only on the four content forms *\/\n .bd-post p a, .bd-post li a, .bd-post blockquote a, .bd-post td a {\n color: var(--accent-text);\n text-decoration: underline;\n text-underline-offset: 2px;\n }\n .bd-post p a:hover, .bd-post li a:hover, .bd-post td a:hover { color: var(--accent-hover); }\n\n \/* PROSE SPACING \u2014 fixed standard, brand header heading values *\/\n .bd-post h1 { font-family: \"Roboto\", sans-serif; font-weight: 600; font-size: 34px; line-height: 1.2; color: var(--heading-ink); margin: 0 0 16px; }\n .bd-post h2 { font-family: \"Roboto\", sans-serif; font-weight: 700; font-size: 34px; line-height: 1.2; color: var(--heading-ink); margin: 48px 0 16px; }\n .bd-post h3 { font-family: \"Roboto\", sans-serif; font-weight: 700; font-size: 24px; line-height: 1.25; color: var(--heading-ink); margin: 32px 0 12px; }\n .bd-post p { margin-top: 0; margin-bottom: 1em; }\n .bd-post ul, .bd-post ol { margin: 0 0 1em; padding-left: 1.5em; }\n .bd-post li { margin-bottom: 0.5em; }\n .bd-post ul li::marker, .bd-post ol li::marker { color: var(--accent-text); }\n .bd-post strong { font-weight: 700; color: var(--heading-ink); }\n\n \/* selector hygiene: box-model only via specific classes *\/\n .bd-post [class*=\"bp-\"], .bd-post [class*=\"rich-\"] { box-sizing: border-box; }\n .bd-post .bd-post-article > .rich-checklist,\n .bd-post .bd-post-article > .rich-callout,\n .bd-post .bd-post-article > .rich-steps,\n .bd-post .bd-post-article > .bp-takeaway-card { margin: var(--gap-normal) 0; }\n .bd-post .bd-post-article > .bp-specnote-card { margin: var(--gap-section) 0; }\n .bd-post .bd-post-article > .bp-cta-end { margin: var(--gap-section) 0; }\n\n \/* ===== Rich elements (content-side authored visual blocks) ===== *\/\n .bd-post .table-wrapper { overflow-x: auto; margin: var(--gap-normal) 0; }\n .bd-post table { width: 100%; border-collapse: collapse; font-size: 15px; }\n .bd-post th {\n background: var(--card-fill); color: var(--heading-ink); font-weight: 700;\n text-align: left; padding: 12px 16px;\n border: 1px solid var(--card-border); border-bottom: 2px solid var(--card-border);\n }\n .bd-post td { padding: 12px 16px; border: 1px solid var(--card-border); color: var(--text-primary); vertical-align: top; }\n .bd-post .rich-matrix tbody td:first-child { font-weight: 700; }\n .bd-post .rich-matrix { border: 1px solid var(--card-border); }\n\n .bd-post .rich-checklist { background: var(--card-fill); border: 1px solid var(--card-border); border-radius: 8px; padding: var(--pad-standard); }\n .bd-post .rich-checklist-title, .bd-post .rich-steps-title, .bd-post .bp-takeaway-title {\n font-weight: 700; font-size: 17px; color: var(--heading-ink); margin: 0 0 12px;\n }\n .bd-post .rich-icon { display: inline-flex; vertical-align: -0.2em; margin-right: 8px; color: var(--accent-on-tint); }\n .bd-post .rich-icon svg, .bd-post .rich-item-icon svg { width: 18px; height: 18px; }\n .bd-post .rich-checklist-list { list-style: none; padding-left: 0; margin: 0; }\n .bd-post .rich-checklist-list li { display: flex; align-items: flex-start; gap: 10px; margin-bottom: 10px; }\n .bd-post .rich-checklist-list li:last-child { margin-bottom: 0; }\n .bd-post .rich-item-icon { display: inline-flex; color: var(--accent-on-tint); flex: 0 0 auto; margin-top: 2px; }\n\n .bd-post .rich-callout { background: var(--card-fill); border: 1px solid var(--card-border); border-left: 4px solid var(--card-border); border-radius: 8px; padding: var(--pad-standard); display: flex; align-items: flex-start; gap: 14px; }\n .bd-post .rich-callout-icon { display: inline-flex; color: var(--accent-text); flex: 0 0 auto; }\n .bd-post .rich-callout-icon svg { width: 22px; height: 22px; }\n .bd-post .rich-callout p { margin: 0; }\n\n .bd-post .rich-steps { background: var(--card-fill); border: 1px solid var(--card-border); border-radius: 8px; padding: var(--pad-standard); }\n .bd-post .rich-steps-list { list-style: none; padding-left: 0; margin: 0; counter-reset: bdstep; }\n .bd-post .rich-steps-list li { display: flex; align-items: flex-start; gap: 12px; margin-bottom: 10px; }\n .bd-post .rich-steps-list li:last-child { margin-bottom: 0; }\n .bd-post .rich-step-num {\n flex: 0 0 auto; width: 24px; height: 24px; border-radius: 50%;\n background: var(--inverse-bg); color: var(--inverse-text);\n font-weight: 700; font-size: 13px;\n display: inline-flex; align-items: center; justify-content: center; margin-top: 1px;\n }\n\n \/* ===== BP-specnote (\u7ad94, plan) ===== *\/\n .bd-post .bp-specnote-card { background: var(--card-fill); border: 1px solid var(--card-border); border-radius: 8px; padding: var(--pad-standard); margin: var(--gap-section) 0; }\n .bd-post .bp-specnote-cells { display: flex; gap: 24px; }\n .bd-post .bp-specnote-cell { flex: 1; min-width: 0; }\n .bd-post .bp-specnote-cell + .bp-specnote-cell { border-left: 1px solid var(--card-border); padding-left: 24px; }\n .bd-post .bp-specnote-label { font-weight: 700; font-size: 15px; color: var(--accent-on-tint); margin: 0 0 4px; }\n .bd-post .bp-specnote-text { font-size: 15px; color: var(--text-primary); margin: 0; }\n .bd-post .bp-specnote-foot { font-size: 14px; color: var(--card-secondary); margin: 16px 0 0; }\n\n \/* ===== BP-takeaway (\u7ad96, plan) ===== *\/\n .bd-post .bp-takeaway-card { background: var(--card-fill); border: 2px solid var(--card-border); border-radius: 8px; padding: var(--pad-standard); }\n .bd-post .bp-takeaway-title { display: flex; align-items: center; gap: 8px; }\n .bd-post .bp-takeaway-title .bp-takeaway-icon { display: inline-flex; color: var(--accent-on-tint); }\n .bd-post .bp-takeaway-title .bp-takeaway-icon svg { width: 20px; height: 20px; }\n .bd-post .bp-takeaway-title span { margin-right: 0; }\n .bd-post .bp-takeaway-rows { display: flex; flex-direction: column; }\n .bd-post .bp-takeaway-row { display: flex; align-items: flex-start; gap: 12px; padding: 12px 0; border-top: 1px solid var(--card-border); }\n .bd-post .bp-takeaway-row:first-child { border-top: none; padding-top: 0; }\n .bd-post .bp-takeaway-row:last-child { padding-bottom: 0; }\n .bd-post .bp-takeaway-num {\n flex: 0 0 auto; width: 28px; height: 28px; border-radius: 50%;\n background: var(--inverse-bg); color: var(--inverse-text);\n font-weight: 700; font-size: 14px;\n display: inline-flex; align-items: center; justify-content: center; margin-top: 1px;\n }\n .bd-post .bp-takeaway-text { font-size: 15px; color: var(--text-primary); margin: 0; }\n\n \/* ===== End CTA (plan cta-states) ===== *\/\n .bd-post .bp-cta-end { background: var(--inverse-bg); padding: 40px 32px; display: flex; flex-direction: column; align-items: center; gap: 16px; margin: var(--gap-section) 0; }\n .bd-post .bp-cta-end-title { font-family: \"Roboto\", sans-serif; font-weight: 700; font-size: 26px; line-height: 1.2; color: var(--inverse-text); text-align: center; margin: 0; }\n .bd-post .bp-cta-end-sub { font-size: 16px; color: var(--inverse-text-2); text-align: center; max-width: 560px; margin: 0; }\n .bd-post .bp-cta-end-btn {\n display: inline-flex; align-items: center; gap: 8px;\n background: var(--accent-hot); color: var(--btn-ink);\n font-family: \"Manrope\", sans-serif; font-weight: 700; font-size: 16px; line-height: 1.2;\n padding: 12px 28px; border-radius: 8px; text-decoration: none;\n border: none; cursor: pointer;\n }\n .bd-post .bp-cta-end-btn svg { width: 16px; height: 16px; }\n .bd-post .bp-cta-end-btn:hover { background: var(--btn-white); color: var(--btn-ink); }\n\n \/* ===== References ===== *\/\n .bd-post .bd-refs-title { font-weight: 700; font-size: 15px; color: var(--text-primary); margin: 48px 0 12px; }\n .bd-post .bd-refs { font-size: 14px; color: var(--text-secondary); padding-left: 1.5em; }\n .bd-post .bd-refs li { margin-bottom: 6px; }\n .bd-post .bd-refs li a { color: var(--accent-text); text-decoration: underline; }\n .bd-post .bd-refs li a:hover { color: var(--accent-hover); }\n\n \/* ===== Motion (sanctioned set, gated) ===== *\/\n @media (prefers-reduced-motion: no-preference) {\n @supports (animation-timeline: view()) {\n .bd-post .bd-reveal { animation: bd-fade-in linear both; animation-timeline: view(); animation-range: entry 0% entry 35%; }\n @keyframes bd-fade-in { from { opacity: 0; } to { opacity: 1; } }\n }\n .bd-post h2 { transition: color .2s ease-out, transform .2s ease-out; }\n .bd-post h2:hover { color: var(--accent-text); transform: scale(1.02); }\n .bd-post .bd-post-article a { transition: color .2s ease-out, text-decoration-color .2s ease-out; }\n .bd-post .bp-specnote-card, .bd-post .bp-takeaway-card { transition: transform .2s ease-out, box-shadow .2s ease-out; }\n .bd-post .bp-specnote-card:hover, .bd-post .bp-takeaway-card:hover { transform: translateY(-2px); box-shadow: 0 6px 18px rgba(0,0,0,0.08); }\n .bd-post .bp-takeaway-row { transition: color .2s ease-out; }\n .bd-post .bp-takeaway-row:hover .bp-takeaway-text { color: var(--accent-on-tint); }\n .bd-post .bp-cta-end-btn { transition: background .2s ease-out, color .2s ease-out, transform .2s ease-out; }\n .bd-post .bp-cta-end-btn:hover { transform: translateY(-2px); }\n }\n\n @media (max-width: 767px) {\n .bd-post { padding: 16px; }\n .bd-post h1 { font-size: 22px; }\n .bd-post h2 { font-size: 26px; margin-top: 32px; }\n .bd-post h3 { font-size: 20px; margin-top: 24px; }\n .bd-post .bp-specnote-cells { flex-direction: column; gap: 0; }\n .bd-post .bp-specnote-cell + .bp-specnote-cell { border-left: none; border-top: 1px solid var(--card-border); padding-left: 0; padding-top: 16px; margin-top: 16px; }\n .bd-post .bp-cta-end { padding: 24px 16px; }\n .bd-post .bp-cta-end-title { font-size: 20px; }\n }\n <\/style>\n <article class=\"bd-post-article\">\n\n <p>B\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u1ee7a m\u1ed9t b\u1ed9 ngu\u1ed3n cho bi\u1ebft \u0111\u1ed9 g\u1ee3n l\u00e0 \u201c\u2264100 mVp-p\u201d. B\u1ea1n k\u1ebft n\u1ed1i m\u00e1y hi\u1ec7n s\u00f3ng v\u1edbi \u0111\u1ea7u ra v\u00e0 th\u1ea5y d\u1ea1ng s\u00f3ng tr\u00f4ng ho\u00e0n to\u00e0n kh\u00e1c v\u1edbi d\u1ea1ng s\u00f3ng r\u0103ng c\u01b0a 100 mV s\u1ea1ch, trong khi m\u1ed9t ng\u01b0\u1eddi \u0111am m\u00ea \u0111i\u1ec7n t\u1eed \u1edf cu\u1ed1i h\u00e0nh lang v\u1eeba \u0111o \u0111\u01b0\u1ee3c 1,4 Vp-p \u1edf m\u1ee9c 5 V tr\u00ean b\u1ed9 ngu\u1ed3n b\u00e0n m\u1edbi c\u1ee7a anh \u1ea5y v\u00e0 mu\u1ed1n bi\u1ebft li\u1ec7u n\u00f3 c\u00f3 b\u1ecb h\u1ecfng kh\u00f4ng (<a href=\"https:\/\/www.reddit.com\/r\/AskElectronics\/comments\/1gm8h7m\/what_is_acceptable_noiseripple_on_cheap\/\" target=\"_blank\" rel=\"noopener\">Reddit r\/AskElectronics<\/a>, 2025). C\u1ea3 hai b\u1ea1n \u0111\u1ec1u \u0111ang nh\u00ecn v\u00e0o c\u00f9ng m\u1ed9t trang c\u1ee7a c\u00e2u chuy\u1ec7n: t\u1eeb \u201cripple\u201d \u0111ang g\u00e1nh v\u00e1c qu\u00e1 nhi\u1ec1u \u00fd ngh\u0129a. \u0110\u1eb1ng sau n\u00f3 \u1ea9n ch\u1ee9a b\u1ed1n t\u00edn hi\u1ec7u kh\u00e1c nhau v\u1edbi b\u1ed1n nguy\u00ean nh\u00e2n kh\u00e1c nhau, b\u1ed1n v\u1ea5n \u0111\u1ec1 \u0111o l\u01b0\u1eddng kh\u00e1c nhau v\u00e0 b\u1ed1n quan ni\u1ec7m kh\u00e1c nhau v\u1ec1 m\u1ee9c \u201cch\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c\u201d. C\u1ea9m nang n\u00e0y s\u1ebd ph\u00e2n t\u00e1ch c\u00e1c y\u1ebfu t\u1ed1 \u0111\u00f3, sau \u0111\u00f3 cung c\u1ea5p cho b\u1ea1n m\u1ed9t khu\u00f4n kh\u1ed5 \u0111\u1ec3 quy\u1ebft \u0111\u1ecbnh m\u1ee9c \u0111\u1ed9 \u201cs\u1ea1ch\u201d th\u1ef1c s\u1ef1 c\u1ea7n thi\u1ebft cho \u0111\u01b0\u1eddng d\u1eabn DC c\u1ee7a b\u1ea1n.<\/p>\n <img decoding=\"async\" src=\"https:\/\/www.omch.com\/wp-content\/uploads\/2026\/09\/Power-Supply-Ripple-1.webp\" style=\"width: 512px; height: 384px; max-width: 100%; object-fit: cover; border-radius: 12px; margin: 30px auto; display: block; box-shadow: 10px 10px 60px 0px rgba(210, 221, 224, 0.35); transition: all 0.3s ease; cursor: pointer;\" onmouseover=\"this.style.transform='translateY(-5px) scale(1.03)'; this.style.boxShadow='15px 25px 80px 0px rgba(210, 221, 224, 0.45)'\" onmouseout=\"this.style.transform='translateY(0) scale(1)'; this.style.boxShadow='10px 10px 60px 0px rgba(210, 221, 224, 0.35)'\"> \n <h2>Dao \u0111\u1ed9ng ngu\u1ed3n th\u1ef1c s\u1ef1 l\u00e0 g\u00ec: B\u1ed1n t\u00edn hi\u1ec7u \u1ea9n trong \u0111\u1ea7u ra DC c\u1ee7a b\u1ea1n<\/h2>\n\n <p>Ripple l\u00e0 dao \u0111\u1ed9ng \u0111\u1ecbnh k\u1ef3 c\u00f2n l\u1ea1i c\u1ee7a \u0111i\u1ec7n \u00e1p m\u1ed9t chi\u1ec1u t\u1ea1i \u0111\u1ea7u ra c\u1ee7a b\u1ed9 ngu\u1ed3n (<a href=\"https:\/\/en.wikipedia.org\/wiki\/Ripple_(electrical)\" target=\"_blank\" rel=\"noopener\">Wikipedia, \u201cRipple (\u0111i\u1ec7n)\u201d<\/a>). \u0110\u1ecbnh ngh\u0129a \u0111\u00f3 l\u00e0 ch\u00ednh x\u00e1c nh\u01b0ng b\u1ea3n th\u00e2n n\u00f3 th\u00ec v\u00f4 d\u1ee5ng, b\u1edfi v\u00ec nh\u1eefng g\u00ec b\u1ea1n th\u1ea5y tr\u00ean m\u00e1y hi\u1ec7n s\u00f3ng kh\u00f4ng bao gi\u1edd ch\u1ec9 l\u00e0 m\u1ed9t t\u00edn hi\u1ec7u duy nh\u1ea5t. C\u00f3 b\u1ed1n th\u00e0nh ph\u1ea7n \u0111i k\u00e8m tr\u00ean \u0111\u01b0\u1eddng \u0111i\u1ec7n m\u1ed9t chi\u1ec1u \u0111\u00f3, v\u00e0 ch\u1ec9 c\u00f3 m\u1ed9t trong s\u1ed1 ch\u00fang l\u00e0 th\u1ee9 m\u00e0 c\u00e1c t\u00e0i li\u1ec7u k\u1ef9 thu\u1eadt g\u1ecdi l\u00e0 \u201cripple\u201d:<\/p>\n\n <div class=\"table-wrapper\">\n <table class=\"rich-table\">\n <thead><tr><th>Th\u00e0nh ph\u1ea7n<\/th><th>Ngu\u1ed3n<\/th><th>T\u1ea7n s\u1ed1<\/th><th>Trong th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u1ee7a b\u1ea3ng d\u1eef li\u1ec7u?<\/th><th>Ai l\u00e0 ng\u01b0\u1eddi ph\u1ea3i g\u00e1nh ch\u1ecbu h\u1eadu qu\u1ea3<\/th><\/tr><\/thead>\n <tbody>\n <tr><td>C\u1eb7n trong \u0111\u01b0\u1eddng \u1ed1ng ch\u00ednh<\/td><td>L\u1ecdc ngu\u1ed3n tuy\u1ebfn t\u00ednh \u1edf t\u1ea7n s\u1ed1 50\/60 Hz<\/td><td>50\/60 Hz + s\u00f3ng h\u00e0i<\/td><td>C\u00f3 (ngu\u1ed3n \u0111i\u1ec7n tuy\u1ebfn t\u00ednh)<\/td><td>thi\u1ebft b\u1ecb \u00e2m thanh v\u00e0 ph\u00e1t thanh (ti\u1ebfng \u00f9), c\u00e1c lo\u1ea1i kh\u00e1c hi\u1ebfm khi<\/td><\/tr>\n <tr><td>Dao \u0111\u1ed9ng chuy\u1ec3n m\u1ea1ch<\/td><td>chuy\u1ec3n m\u1ea1ch c\u01a1 b\u1ea3n th\u00f4ng qua b\u1ed9 l\u1ecdc \u0111\u1ea7u ra<\/td><td>t\u1eeb h\u00e0ng ch\u1ee5c kHz \u0111\u1ebfn d\u1ea3i t\u1ea7n s\u1ed1 MHz th\u1ea5p<\/td><td>C\u00f3 (theo h\u1ea7u h\u1ebft c\u00e1c th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u1ee7a SMPS)<\/td><td>c\u00f4ng c\u1ee5 so s\u00e1nh th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt<\/td><\/tr>\n <tr><td>C\u00e1c \u0111\u1ec9nh nhi\u1ec5u do chuy\u1ec3n m\u1ea1ch<\/td><td>hi\u1ec7n t\u01b0\u1ee3ng gh\u00e9p n\u1ed1i k\u00fd sinh c\u1ee7a c\u00e1c c\u1ea1nh chuy\u1ec3n m\u1ea1ch nhanh<\/td><td>b\u0103ng th\u00f4ng r\u1ed9ng MHz+<\/td><td>hi\u1ebfm khi<\/td><td>thi\u1ebft b\u1ecb t\u01b0\u01a1ng t\u1ef1, c\u1ea3m bi\u1ebfn, b\u00e1nh r\u0103ng ch\u00ednh x\u00e1c<\/td><\/tr>\n <tr><td>D\u00f2ng \u0111i\u1ec7n tho\u00e1ng qua v\u00e0 d\u00f2ng \u0111i\u1ec7n ti\u00eam v\u00e0o<\/td><td>c\u00e1c b\u01b0\u1edbc t\u1ea3i, ph\u1ea3n \u1ee9ng c\u1ea3m \u1ee9ng, \u0111\u1ed9ng c\u01a1\/c\u00f4ng t\u1eafc t\u01a1<\/td><td>c\u00e1c s\u1ef1 ki\u1ec7n ch\u1ec9 di\u1ec5n ra m\u1ed9t l\u1ea7n<\/td><td>kh\u00f4ng<\/td><td>thi\u1ebft b\u1ecb hi\u1ec7n tr\u01b0\u1eddng<\/td><\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <p>T\u1ea1i sao vi\u1ec7c ph\u00e2n chia n\u00e0y l\u1ea1i quan tr\u1ecdng? B\u1ed1n th\u00e0nh ph\u1ea7n n\u00e0y ch\u00eanh l\u1ec7ch v\u1ec1 t\u1ea7n s\u1ed1 t\u1eeb ba \u0111\u1ebfn b\u1ed1n b\u1eadc \u0111\u1ed9 l\u1edbn, ch\u00fang c\u1ea7n c\u00e1c thi\u1ebft l\u1eadp \u0111o l\u01b0\u1eddng kh\u00e1c nhau, g\u00e2y h\u01b0 h\u1ecfng cho c\u00e1c t\u1ea3i kh\u00e1c nhau, v\u00e0 m\u1ed9t gi\u1edbi h\u1ea1n duy nh\u1ea5t \u201c\u2264100 mVp-p\u201d ch\u1ec9 bao ph\u1ee7 ch\u00ednh x\u00e1c m\u1ed9t trong s\u1ed1 ch\u00fang. H\u1ec7 s\u1ed1 g\u1ee3n (ripple factor \u2013 t\u1ef7 l\u1ec7 RMS c\u0169 RF = V~AC \/ V~DC) c\u0169ng ch\u1ec9 m\u00f4 t\u1ea3 ph\u1ea7n dao \u0111\u1ed9ng \u0111\u1ecbnh k\u1ef3 m\u01b0\u1ee3t m\u00e0, v\u00e0 v\u00ec \u0111\u00e2y l\u00e0 t\u1ef7 l\u1ec7 RMS n\u00ean n\u00f3 lu\u00f4n tr\u00f4ng l\u1edbn h\u01a1n con s\u1ed1 mVp-p m\u00e0 m\u1ecdi ng\u01b0\u1eddi th\u01b0\u1eddng tr\u00edch d\u1eabn ng\u00e0y nay. \u0110\u00f3 l\u00e0 l\u00fd do t\u1ea1i sao hai gi\u00e1 tr\u1ecb n\u00e0y d\u01b0\u1eddng nh\u01b0 kh\u00f4ng bao gi\u1edd kh\u1edbp nhau.<\/p>\n\n <p>M\u1ed9t ch\u00fat l\u1ea1c \u0111\u1ec1, v\u00ec k\u1ebft qu\u1ea3 t\u00ecm ki\u1ebfm c\u1ee9 li\u00ean t\u1ee5c \u0111\u1ec1 c\u1eadp \u0111\u1ebfn kh\u00e1i ni\u1ec7m n\u00e0y: \u201cdao \u0111\u1ed9ng c\u1ee7a m\u00e1y ph\u00e1t \u0111i\u1ec7n\u201d \u2014 th\u00e0nh ph\u1ea7n d\u00f2ng \u0111i\u1ec7n xoay chi\u1ec1u trong \u0111\u1ea7u ra s\u1ea1c c\u1ee7a \u00f4 t\u00f4 m\u00e0 c\u00e1c k\u1ef9 thu\u1eadt vi\u00ean ki\u1ec3m tra \u0111\u1ec3 \u0111\u00e1nh gi\u00e1 t\u00ecnh tr\u1ea1ng c\u1ee7a \u0111i-\u1ed1t \u2014 l\u00e0 m\u1ed9t th\u00f4ng s\u1ed1 \u0111o l\u01b0\u1eddng kh\u00e1c thu\u1ed9c v\u1ec1 m\u1ed9t h\u1ec7 th\u1ed1ng kh\u00e1c. C\u00f9ng m\u1ed9t t\u1eeb, nh\u01b0ng thu\u1ed9c l\u0129nh v\u1ef1c kh\u00e1c; h\u01b0\u1edbng d\u1eabn n\u00e0y ch\u1ec9 t\u1eadp trung v\u00e0o c\u00e1c b\u1ed9 ngu\u1ed3n.<\/p>\n\n <h2>C\u00e1ch \u0111o \u0111\u1ed9 g\u1ee3n c\u1ee7a ngu\u1ed3n \u0111i\u1ec7n: L\u1ea5y \u0111\u01b0\u1ee3c con s\u1ed1 \u0111\u00e1ng tin c\u1eady<\/h2>\n\n <p>H\u1ea7u h\u1ebft c\u00e1c gi\u00e1 tr\u1ecb \u201cripple x\u1ea5u\u201d \u0111\u1ec1u l\u00e0 k\u1ebft qu\u1ea3 \u0111o kh\u00f4ng ch\u00ednh x\u00e1c. C\u00f3 ba th\u00f4ng s\u1ed1 quy\u1ebft \u0111\u1ecbnh li\u1ec7u con s\u1ed1 \u0111\u00f3 c\u00f3 \u00fd ngh\u0129a g\u00ec hay kh\u00f4ng:<\/p>\n\n <ul>\n <li><strong>Kh\u1edbp n\u1ed1i:<\/strong> S\u1eed d\u1ee5ng gh\u00e9p n\u1ed1i AC \u0111\u1ec3 ng\u0103n ch\u1eb7n th\u00e0nh ph\u1ea7n DC v\u00e0 ch\u1ec9 khu\u1ebfch \u0111\u1ea1i th\u00e0nh ph\u1ea7n d\u01b0. C\u00f3 m\u1ed9t s\u1ed1 l\u01b0\u1ee3ng \u0111\u00e1ng ng\u1ea1c nhi\u00ean c\u00e1c t\u00e0i li\u1ec7u h\u01b0\u1edbng d\u1eabn l\u1ea1i qu\u00ean \u0111\u1ec1 c\u1eadp \u0111\u1ebfn \u0111i\u1ec1u n\u00e0y (<a href=\"https:\/\/www.eevblog.com\/forum\/beginners\/measure-power-supply-ripple-with-this-technique\/\" target=\"_blank\" rel=\"noopener\">Di\u1ec5n \u0111\u00e0n EEVblog<\/a>, 2021).<\/li>\n <li><strong>B\u0103ng th\u00f4ng:<\/strong> Gi\u1edbi h\u1ea1n 20 MHz tr\u00ean nhi\u1ec1u m\u00e1y hi\u1ec7n s\u00f3ng xu\u1ea5t ph\u00e1t t\u1eeb c\u00e1c ti\u00eau chu\u1ea9n ki\u1ec3m tra c\u0169. Gi\u1edbi h\u1ea1n n\u00e0y che gi\u1ea5u c\u00e1c th\u00e0nh ph\u1ea7n t\u1ea7n s\u1ed1 cao, c\u00f3 d\u1ea1ng \u0111\u1ec9nh nh\u1ecdn c\u1ee7a c\u00e1c b\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch hi\u1ec7n \u0111\u1ea1i. N\u1ebfu b\u1ea1n \u0111ang so s\u00e1nh v\u1edbi b\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt, h\u00e3y s\u1eed d\u1ee5ng c\u00f9ng b\u0103ng th\u00f4ng m\u00e0 nh\u00e0 s\u1ea3n xu\u1ea5t \u0111\u00e3 d\u00f9ng (th\u01b0\u1eddng l\u00e0 20 MHz); n\u1ebfu b\u1ea1n \u0111ang t\u00ecm ki\u1ebfm m\u1ed9t s\u1ef1 c\u1ed1 th\u1ef1c t\u1ebf, h\u00e3y m\u1edf r\u1ed9ng b\u0103ng th\u00f4ng t\u1ed1i \u0111a. S\u1ef1 th\u1eadt c\u00f3 th\u1ec3 tr\u00f4ng r\u1ea5t \u0111\u00e1ng s\u1ee3.<\/li>\n <li><strong>K\u1ebft n\u1ed1i \u0111\u1ea7u d\u00f2:<\/strong> D\u00e2y n\u1ed1i \u0111\u1ea5t d\u00e0i tr\u00ean \u0111\u1ea7u d\u00f2 ti\u00eau chu\u1ea9n \u0111\u00f3ng vai tr\u00f2 nh\u01b0 m\u1ed9t \u0103ng-ten. V\u00f2ng l\u1eb7p n\u1ed1i \u0111\u1ea5t c\u1ee7a n\u00f3 thu nh\u1eadn c\u00e1c tr\u01b0\u1eddng t\u1eeb do d\u00f2ng \u0111i\u1ec7n chuy\u1ec3n m\u1ea1ch t\u1ea1o ra v\u00e0 hi\u1ec3n th\u1ecb c\u00e1c \u0111\u1ec9nh gi\u1ea3. Ch\u00ednh v\u00ec l\u00fd do \u0111\u00f3 m\u00e0 c\u00e2u n\u00f3i \u201cT\u00f4i \u0111\u00e3 th\u00eam t\u1ee5 \u0111i\u1ec7n nh\u01b0ng \u0111\u1ed9 g\u1ee3n v\u1eabn cao\u201d th\u01b0\u1eddng l\u00e0 do v\u1ea5n \u0111\u1ec1 \u1edf \u0111\u1ea7u d\u00f2, ch\u1ee9 kh\u00f4ng ph\u1ea3i do b\u1ed9 ngu\u1ed3n (<a href=\"https:\/\/electronics.stackexchange.com\/questions\/707711\/switching-power-supply-has-high-ripple-voltage-no-matter-how-many-capacitors-are\" target=\"_blank\" rel=\"noopener\">StackExchange v\u1ec1 \u0110i\u1ec7n t\u1eed<\/a>, 2024). S\u1eed d\u1ee5ng k\u1ebft n\u1ed1i \u0111\u1ea7u v\u00e0 th\u00e2n, n\u1ed1i \u0111\u1ea5t b\u1eb1ng k\u1eb9p gi\u1ea5y ho\u1eb7c \u0111\u1ea7u n\u1ed1i \u0111\u1ed3ng tr\u1ee5c 50 \u03a9 g\u1ea7n t\u1ee5 \u0111i\u1ec7n \u0111\u1ea7u ra (<a href=\"https:\/\/www.analog.com\/en\/resources\/app-notes\/an-1144.html\" target=\"_blank\" rel=\"noopener\">Analog Devices AN-1144<\/a>).<\/li>\n <\/ul>\n\n \n <div class=\"rich-checklist\">\n <p class=\"rich-checklist-title\"><span class=\"rich-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"m3 17 2 2 4-4\"\/><path d=\"m3 7 2 2 4-4\"\/><path d=\"M13 6h8\"\/><path d=\"M13 12h8\"\/><path d=\"M13 18h8\"\/><\/svg><\/span>Tr\u01b0\u1edbc khi tin t\u01b0\u1edfng v\u00e0o m\u1ed9t k\u1ebft qu\u1ea3 \u0111o s\u00f3ng g\u1ee3n<\/p>\n <ul class=\"rich-checklist-list\">\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>K\u1ebft n\u1ed1i c\u1eb7p AC cho k\u00eanh m\u00e1y hi\u1ec7n s\u00f3ng<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>R\u00fat ng\u1eafn \u0111\u01b0\u1eddng d\u1eabn n\u1ed1i \u0111\u1ea5t (ki\u1ec3u \u0111\u1ea7u v\u00e0 th\u00e2n, ki\u1ec3u k\u1eb9p gi\u1ea5y ho\u1eb7c \u0111\u1ea7u n\u1ed1i 50 \u03a9 t\u1ea1i t\u1ee5 \u0111i\u1ec7n \u0111\u1ea7u ra)<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>N\u1ebfu b\u1ea1n \u0111ang so s\u00e1nh v\u1edbi th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt, h\u00e3y \u0111\u1ea3m b\u1ea3o b\u0103ng th\u00f4ng c\u1ee7a nh\u00e0 cung c\u1ea5p ph\u00f9 h\u1ee3p v\u1edbi th\u00f4ng s\u1ed1 \u0111\u00f3<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>H\u00e3y m\u1edf to\u00e0n b\u1ed9 b\u0103ng th\u00f4ng n\u1ebfu b\u1ea1n \u0111ang theo d\u00f5i c\u00e1c \u0111\u1ec9nh \u0111\u1ed9t bi\u1ebfn<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>H\u00e3y quan s\u00e1t nhi\u1ec1u chu k\u1ef3 chuy\u1ec3n m\u1ea1ch, ch\u1ee9 kh\u00f4ng ch\u1ec9 m\u1ed9t chu k\u1ef3<\/li>\n <\/ul>\n <\/div>\n\n <p>C\u00f3 m\u1ed9t lo\u1ea1i nh\u1ea1c c\u1ee5 c\u1ea7n c\u00f3 c\u1ea3nh b\u00e1o ri\u00eang.<\/p>\n\n <p>\u0110\u00f3 l\u00e0 th\u1ee9 m\u00e0 h\u1ea7u h\u1ebft m\u1ecdi ng\u01b0\u1eddi th\u01b0\u1eddng ch\u1ecdn \u0111\u1ea7u ti\u00ean:<\/p>\n\n \n <div class=\"rich-callout\">\n <span class=\"rich-callout-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"m21.73 18-8-14a2 2 0 0 0-3.48 0l-8 14A2 2 0 0 0 4 20h16a2 2 0 0 0 1.73-2Z\"\/><path d=\"M12 9v4\"\/><path d=\"M12 17h.01\"\/><\/svg><\/span>\n <p>M\u1ed9t \u0111\u1ed3ng h\u1ed3 v\u1ea1n n\u0103ng \u1edf ch\u1ebf \u0111\u1ed9 \u0111o \u0111i\u1ec7n \u00e1p xoay chi\u1ec1u (AC) kh\u00f4ng th\u1ec3 cung c\u1ea5p cho b\u1ea1n th\u00f4ng s\u1ed1 v\u1ec1 \u0111\u1ed9 g\u1ee3n. D\u1ea3i t\u1ea7n s\u1ed1 v\u00e0 ph\u01b0\u01a1ng ph\u00e1p t\u00ednh trung b\u00ecnh RMS c\u1ee7a n\u00f3 l\u00e0m m\u1edd \u0111i c\u00e1c \u0111\u1ec9nh \u0111i\u1ec7n \u00e1p do chuy\u1ec3n m\u1ea1ch v\u00e0 \u0111\u1ed9 g\u1ee3n, bi\u1ebfn ch\u00fang th\u00e0nh m\u1ed9t con s\u1ed1 v\u00f4 ngh\u0129a. Ch\u1ec9 n\u00ean s\u1eed d\u1ee5ng n\u00f3 nh\u01b0 m\u1ed9t c\u00e1ch ki\u1ec3m tra s\u01a1 b\u1ed9 \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh \u201cc\u00f3 d\u00f2ng \u0111i\u1ec7n hay kh\u00f4ng\u201d.<\/p>\n <\/div>\n\n <p>M\u1eb9o \u201chai t\u1ee5 \u0111i\u1ec7n \u1edf \u0111\u1ea7u d\u00e2y c\u00e1p\u201d \u0111ang lan truy\u1ec1n tr\u00ean c\u00e1c n\u1ec1n t\u1ea3ng video l\u00e0 m\u1ed9t quy\u1ebft \u0111\u1ecbnh t\u00f9y theo t\u1eebng tr\u01b0\u1eddng h\u1ee3p: n\u00f3 m\u00f4 ph\u1ecfng m\u1ed9t t\u1ea3i \u0111\u01b0\u1ee3c k\u1ebft n\u1ed1i, \u0111i\u1ec1u n\u00e0y th\u1ef1c t\u1ebf h\u01a1n so v\u1edbi vi\u1ec7c ch\u1ec9 s\u1eed d\u1ee5ng ngu\u1ed3n \u0111i\u1ec7n tr\u1ea7n, nh\u01b0ng n\u00f3 c\u0169ng l\u1ecdc b\u1edbt m\u1ed9t s\u1ed1 th\u00f4ng tin m\u00e0 b\u1ea1n th\u1ef1c s\u1ef1 c\u1ea7n quan s\u00e1t (<a href=\"https:\/\/www.eevblog.com\/forum\/beginners\/measure-power-supply-ripple-with-this-technique\/\" target=\"_blank\" rel=\"noopener\">Di\u1ec5n \u0111\u00e0n EEVblog<\/a>, 2021). Tr\u01b0\u1edbc ti\u00ean, h\u00e3y quy\u1ebft \u0111\u1ecbnh xem b\u1ea1n \u0111ang theo \u0111u\u1ed5i t\u00edn hi\u1ec7u n\u00e0o trong b\u1ed1n t\u00edn hi\u1ec7u \u0111\u00f3. Sau \u0111\u00f3, h\u00e3y ch\u1ecdn ph\u01b0\u01a1ng \u00e1n giao d\u1ecbch cho ph\u00e9p t\u00edn hi\u1ec7u \u0111\u00f3 \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n.<\/p>\n\n <h2>M\u1ee9c \u0111\u1ed9 dao \u0111\u1ed9ng c\u1ee7a ngu\u1ed3n \u0111i\u1ec7n n\u00e0o l\u00e0 ch\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c? \u0110i\u1ec1u n\u00e0y ph\u1ee5 thu\u1ed9c v\u00e0o t\u1ea3i<\/h2>\n\n <p>H\u00e3y h\u1ecfi \u201cm\u1ee9c dao \u0111\u1ed9ng n\u00e0o l\u00e0 ch\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c\u201d v\u00e0 b\u1ea1n s\u1ebd nh\u1eadn \u0111\u01b0\u1ee3c nh\u1eefng c\u00e2u tr\u1ea3 l\u1eddi m\u00e2u thu\u1eabn nhau: miliv\u00f4n tuy\u1ec7t \u0111\u1ed1i (ti\u00eau chu\u1ea9n ATX cho ph\u00e9p 120 mVp-p tr\u00ean \u0111\u01b0\u1eddng +12 V v\u00e0 50 mVp-p tr\u00ean c\u00e1c \u0111\u01b0\u1eddng 5 V\/3,3 V, theo <a href=\"https:\/\/www.tomshardware.com\/reviews\/how-we-test-psu,4042-5.html\" target=\"_blank\" rel=\"noopener\">Tom\u2019s Hardware<\/a>), t\u1ef7 l\u1ec7 ph\u1ea7n tr\u0103m (1% l\u00e0 m\u1ed9t quy t\u1eafc kinh nghi\u1ec7m ph\u1ed5 bi\u1ebfn; theo c\u00e1c c\u1ea9m nang c\u1ee7a ARRL, tr\u01b0\u1edbc \u0111\u00e2y th\u01b0\u1eddng khuy\u1ebfn ngh\u1ecb t\u1ef7 l\u1ec7 cao h\u01a1n 5% \u0111\u1ed1i v\u1edbi b\u1ed9 ph\u00e1t CW v\u00e0 3% \u0111\u1ed1i v\u1edbi ngu\u1ed3n c\u1ea5p c\u1ef1c d\u01b0\u01a1ng c\u1ee7a b\u1ed9 khu\u1ebfch \u0111\u1ea1i tuy\u1ebfn t\u00ednh, theo <a href=\"https:\/\/wsjtx.groups.io\/g\/main\/topic\/acceptable_pa_power_supply\/71775932\" target=\"_blank\" rel=\"noopener\">WSJT-X tr\u00ean groups.io<\/a>, 2021), v\u00e0 h\u1ec7 s\u1ed1 dao \u0111\u1ed9ng. Kh\u00f4ng c\u00f3 y\u1ebfu t\u1ed1 n\u00e0o trong s\u1ed1 \u0111\u00f3 l\u00e0 sai; m\u1ed7i y\u1ebfu t\u1ed1 \u0111o l\u01b0\u1eddng m\u1ed9t \u0111\u1ea1i l\u01b0\u1ee3ng kh\u00e1c nhau \u0111\u1ed1i v\u1edbi t\u1eebng lo\u1ea1i t\u1ea3i kh\u00e1c nhau. Khung ph\u00e2n t\u00edch duy nh\u1ea5t c\u00f3 th\u1ec3 \u0111\u1ee9ng v\u1eefng tr\u01b0\u1edbc th\u1ef1c t\u1ebf l\u00e0 c\u00e1ch ti\u1ebfp c\u1eadn d\u1ef1a tr\u00ean lo\u1ea1i t\u1ea3i m\u00e0 b\u1ea1n \u0111ang c\u1ea5p ngu\u1ed3n.<\/p>\n\n <h3>B\u1ed1n m\u1ee9c t\u1ea3i: Ai quan t\u00e2m, v\u00e0 m\u1ee9c \u0111\u1ed9 quan t\u00e2m ra sao?<\/h3>\n\n <ul>\n <li><strong>C\u01a1 ch\u1ebf k\u00edch ho\u1ea1t v\u00e0 kh\u1ea3 n\u0103ng ch\u1ed1ng nhi\u1ec5u (cu\u1ed9n d\u00e2y r\u01a1le, \u0111\u00e8n, m\u00e1y b\u01a1m, t\u1ee7 c\u00f4ng t\u1eafc t\u01a1):<\/strong> S\u1ef1 dao \u0111\u1ed9ng \u1edf \u0111\u00e2y v\u1ec1 c\u01a1 b\u1ea3n l\u00e0 kh\u00f4ng \u0111\u00e1ng k\u1ec3. C\u00e1c t\u1ea3i n\u00e0y c\u00f3 bi\u00ean \u0111\u1ed9 ho\u1ea1t \u0111\u1ed9ng r\u1ea5t l\u1edbn; m\u1ed9t dao \u0111\u1ed9ng 100 mV tr\u00ean \u0111\u01b0\u1eddng ray 24 V l\u00e0 chuy\u1ec7n nh\u1ecf \u0111\u1ed1i v\u1edbi ch\u00fang.<\/li>\n <li><strong>Logic s\u1ed1:<\/strong> H\u1ea7u h\u1ebft c\u00e1c bo m\u1ea1ch logic \u0111\u1ec1u c\u00f3 c\u01a1 ch\u1ebf \u0111i\u1ec1u ch\u1ec9nh n\u1ed9i b\u1ed9 ri\u00eang, gi\u00fap h\u1ea5p th\u1ee5 dao \u0111\u1ed9ng tr\u00ean \u0111\u01b0\u1eddng c\u1ea5p ngu\u1ed3n tr\u01b0\u1edbc khi n\u00f3 t\u00e1c \u0111\u1ed9ng \u0111\u1ebfn chip b\u00e1n d\u1eabn. \u0110i\u1ec1u th\u1ef1c s\u1ef1 g\u00e2y h\u1ea1i cho bo m\u1ea1ch logic l\u00e0 hi\u1ec7n t\u01b0\u1ee3ng s\u1ee5t \u00e1p t\u1ea1m th\u1eddi t\u1ea1i \u0111i\u1ec3m t\u1ea3i. \u0110\u00f3 l\u00e0 m\u1ed9t v\u1ea5n \u0111\u1ec1 t\u1ea1m th\u1eddi, ch\u1ee9 kh\u00f4ng ph\u1ea3i v\u1ea5n \u0111\u1ec1 li\u00ean quan \u0111\u1ebfn th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt v\u1ec1 dao \u0111\u1ed9ng.<\/li>\n <li><strong>\u0110o l\u01b0\u1eddng t\u01b0\u01a1ng t\u1ef1 v\u00e0 thu th\u1eadp d\u1eef li\u1ec7u:<\/strong> M\u1ea1ch v\u00f2ng 4\u201320 mA, b\u1ed9 truy\u1ec1n t\u00edn hi\u1ec7u, b\u1ed9 ti\u1ec1n x\u1eed l\u00fd ADC. \u1ede \u0111\u00e2y, \u0111\u1ed9 g\u1ee3n tr\u1ef1c ti\u1ebfp \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn gi\u1edbi h\u1ea1n sai s\u1ed1. M\u1ed9t nguy\u00ean t\u1eafc kinh nghi\u1ec7m \u0111\u01b0\u1ee3c c\u00e1c k\u1ef9 s\u01b0 th\u1ef1c t\u1ebf \u0111\u1ec1 c\u1eadp l\u00e0 m\u1ee9c 30 mV c\u00f3 th\u1ec3 ch\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c cho c\u00e1c \u1ee9ng d\u1ee5ng th\u00f4ng th\u01b0\u1eddng, nh\u01b0ng l\u1ea1i qu\u00e1 cao \u0111\u1ed1i v\u1edbi m\u1ea1ch logic ch\u00ednh x\u00e1c \u0111i\u1ec7n \u00e1p th\u1ea5p \u1edf m\u1ee9c 1,8 V (<a href=\"https:\/\/electronics.stackexchange.com\/questions\/501187\/output-voltage-ripple-considerations\" target=\"_blank\" rel=\"noopener\">StackExchange v\u1ec1 \u0110i\u1ec7n t\u1eed<\/a>, 2020); c\u00e1ch suy lu\u1eadn n\u00e0y c\u0169ng \u00e1p d\u1ee5ng \u0111\u01b0\u1ee3c cho b\u1ea5t k\u1ef3 m\u1ea1ch \u0111\u1ea7u v\u00e0o t\u01b0\u01a1ng t\u1ef1 n\u00e0o m\u00e0 \u0111i\u1ec7n \u00e1p tham chi\u1ebfu v\u00e0 t\u00edn hi\u1ec7u c\u00f9ng chia s\u1ebb c\u00f9ng m\u1ed9t c\u1ef1c.<\/li>\n <li><strong>T\u1ea7n s\u1ed1 v\u00f4 tuy\u1ebfn (RF) v\u00e0 \u00e2m thanh:<\/strong> d\u1ea3i t\u1ea7n kh\u00f3 kh\u0103n nh\u1ea5t, n\u01a1i hi\u1ec7n t\u01b0\u1ee3ng g\u1ee3n s\u00f3ng v\u00e0 nhi\u1ec5u bi\u1ebfn th\u00e0nh ti\u1ebfng \u00f9 v\u00e0 c\u00e1c \u0111\u1ec9nh nhi\u1ec5u. \u0110\u00e2y ch\u00ednh l\u00e0 th\u1ebf gi\u1edbi c\u1ee7a c\u00e1c t\u1ef7 l\u1ec7 ph\u1ea7n tr\u0103m ARRL n\u00eau tr\u00ean.<\/li>\n <\/ul>\n\n <h3>T\u1ea1i sao ba thang \u0111o \u201cc\u00f3 th\u1ec3 ch\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c\u201d n\u00e0y l\u1ea1i kh\u00f4ng bao gi\u1edd tr\u00f9ng kh\u1edbp v\u1edbi nhau<\/h3>\n\n <p>Millivolt, ph\u1ea7n tr\u0103m v\u00e0 h\u1ec7 s\u1ed1 dao \u0111\u1ed9ng \u0111o l\u01b0\u1eddng c\u00e1c \u0111\u1ea1i l\u01b0\u1ee3ng kh\u00e1c nhau tr\u00ean c\u00e1c \u0111\u01b0\u1eddng ngu\u1ed3n kh\u00e1c nhau. Dao \u0111\u1ed9ng 100 mV t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi 2% tr\u00ean \u0111\u01b0\u1eddng ngu\u1ed3n 5 V v\u00e0 0,4% tr\u00ean \u0111\u01b0\u1eddng ngu\u1ed3n 24 V. C\u00f9ng m\u1ed9t gi\u00e1 tr\u1ecb v\u1eadt l\u00fd l\u1ea1i \u0111\u01b0a ra nh\u1eefng k\u1ebft lu\u1eadn tr\u00e1i ng\u01b0\u1ee3c t\u00f9y thu\u1ed9c v\u00e0o thang \u0111o m\u00e0 b\u1ea1n tham chi\u1ebfu. H\u1ec7 s\u1ed1 dao \u0111\u1ed9ng c\u00e0ng l\u00e0m t\u00ecnh h\u00ecnh t\u1ed3i t\u1ec7 h\u01a1n: v\u00ec \u0111\u00e2y l\u00e0 t\u1ef7 l\u1ec7 RMS, m\u1ed9t ngu\u1ed3n \u0111i\u1ec7n tr\u00f4ng c\u00f3 v\u1ebb l\u00fd t\u01b0\u1edfng v\u1edbi gi\u00e1 tr\u1ecb \u201c0,07\u201d (7%) theo thang \u0111o n\u00e0y l\u1ea1i tr\u1edf n\u00ean \u0111\u00e1ng lo ng\u1ea1i khi so s\u00e1nh v\u1edbi \u0111\u01b0\u1eddng \u0111i\u1ec7n c\u00f3 bi\u00ean \u0111\u1ed9 \u0111\u1ec9nh-\u0111\u1ec9nh 50 mVp-p. Tr\u01b0\u1edbc khi so s\u00e1nh b\u1ea5t k\u1ef3 hai con s\u1ed1 n\u00e0o, h\u00e3y \u0111\u1eb7t ch\u00fang tr\u00ean c\u00f9ng m\u1ed9t \u0111\u01b0\u1eddng \u0111i\u1ec7n, c\u00f9ng m\u1ed9t thang \u0111o v\u00e0 trong c\u00f9ng \u0111i\u1ec1u ki\u1ec7n. H\u1ea7u h\u1ebft c\u00e1c \u201cl\u1eddi khuy\u00ean m\u00e2u thu\u1eabn\u201d s\u1ebd bi\u1ebfn m\u1ea5t khi b\u1ea1n l\u00e0m nh\u01b0 v\u1eady.<\/p>\n\n <h3>M\u1ed9t ma tr\u1eadn l\u00e0m vi\u1ec7c d\u00e0nh ri\u00eang cho h\u1ec7 th\u1ed1ng Rails c\u1ee7a b\u1ea1n<\/h3>\n\n <p><strong>To\u00e0n b\u1ed9 khung l\u00fd thuy\u1ebft g\u00f3i g\u1ecdn trong m\u1ed9t c\u00e2u: m\u1ed9t thanh ray ho\u00e0n to\u00e0n ph\u00f9 h\u1ee3p v\u1edbi t\u1ee7 r\u01a1le l\u1ea1i c\u00f3 th\u1ec3 l\u00e0 nguy\u00ean nh\u00e2n khi\u1ebfn b\u1ed9 truy\u1ec1n t\u00edn hi\u1ec7u 4\u201320 mA ho\u1ea1t \u0111\u1ed9ng kh\u00f4ng \u1ed5n \u0111\u1ecbnh. H\u00e3y x\u00e1c \u0111\u1ecbnh lo\u1ea1i t\u1ea3i tr\u01b0\u1edbc, sau \u0111\u00f3 m\u1edbi b\u00e0n \u0111\u1ebfn v\u1ea5n \u0111\u1ec1 v\u1ec1 miliv\u00f4n.<\/strong><\/p>\n\n \n <div class=\"table-wrapper\">\n <table class=\"rich-table rich-matrix\">\n <thead><tr><th>Lo\u1ea1i t\u1ea3i<\/th><th>D\u1ea3i \u0111\u1ed9 nh\u1ea1y<\/th><th>D\u1ea5u hi\u1ec7u c\u1ea7n theo d\u00f5i<\/th><th>\u201c\u0110\u1ee7 r\u1ed3i\u201d tr\u00f4ng nh\u01b0 th\u1ebf n\u00e0y<\/th><th>H\u00e0nh \u0111\u1ed9ng<\/th><\/tr><\/thead>\n <tbody>\n <tr><td>Cu\u1ed9n d\u00e2y r\u01a1le, \u0111\u00e8n, c\u00f4ng t\u1eafc t\u01a1, t\u1ee7 c\u00f4ng t\u1eafc t\u01a1<\/td><td>mi\u1ec5n d\u1ecbch<\/td><td>kh\u00f4ng c\u00f3<\/td><td>b\u1ea5t k\u1ef3 gi\u00e1 tr\u1ecb n\u00e0o \u0111\u00e3 \u0111\u01b0\u1ee3c c\u00f4ng b\u1ed1<\/td><td>Th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt h\u1ea7u nh\u01b0 kh\u00f4ng quan tr\u1ecdng (h\u00e3y ch\u1ecdn d\u1ef1a tr\u00ean gi\u00e1 c\u1ea3 v\u00e0 \u0111\u1ed9 b\u1ec1n)<\/td><\/tr>\n <tr><td>B\u1ea3ng m\u1ea1ch MCU\/b\u1ea3ng m\u1ea1ch logic<\/td><td>th\u1ea5p<\/td><td>s\u1ee5t \u00e1p nh\u1ea5t th\u1eddi, kh\u00f4ng ph\u1ea3i dao \u0111\u1ed9ng<\/td><td>trong ph\u1ea1m vi \u0111\u1ea7u v\u00e0o c\u1ee7a b\u1ed9 \u0111i\u1ec1u ch\u1ec9nh tr\u00ean bo m\u1ea1ch<\/td><td>H\u00e3y ki\u1ec3m tra quy \u0111\u1ecbnh \u0111\u1ecba ph\u01b0\u01a1ng, ch\u1ee9 kh\u00f4ng ph\u1ea3i quy \u0111\u1ecbnh c\u1ee7a \u0111\u01b0\u1eddng s\u1eaft<\/td><\/tr>\n <tr><td>M\u1ea1ch v\u00f2ng 4\u201320 mA, b\u1ed9 truy\u1ec1n t\u00edn hi\u1ec7u, b\u1ed9 ti\u1ec1n x\u1eed l\u00fd ADC<\/td><td>cao<\/td><td>s\u00f3ng g\u1ee3n + ti\u1ebfng \u1ed3n<\/td><td>c\u1ea5p \u0111\u1ed9 h\u00e0ng ch\u1ee5c mVp-p ho\u1eb7c cao h\u01a1n, \u0111\u00e3 \u0111\u01b0\u1ee3c ki\u1ec3m ch\u1ee9ng \u1edf d\u00f2ng t\u1ea3i c\u1ee7a b\u1ea1n<\/td><td>Y\u00eau c\u1ea7u th\u00f4ng s\u1ed1 t\u1ed1i \u0111a (kh\u00f4ng ph\u1ea3i gi\u00e1 tr\u1ecb \u0111i\u1ec3n h\u00ecnh), b\u0103ng th\u00f4ng v\u00e0 \u0111i\u1ec1u ki\u1ec7n t\u1ea3i<\/td><\/tr>\n <tr><td>C\u00e1c m\u1ea1ch RF \/ \u00e2m thanh<\/td><td>c\u1ef1c \u0111oan<\/td><td>s\u00f3ng g\u1ee3n + ti\u1ebfng \u1ed3n, t\u1ea5t c\u1ea3 nh\u1eefng th\u1ee9 \u0111\u00f3<\/td><td>th\u1ea5p nh\u1ea5t trong ph\u1ea1m vi ng\u00e2n s\u00e1ch cho ph\u00e9p<\/td><td>h\u00e3y thi\u1ebft k\u1ebf m\u1ed9t m\u1ea1ch \u1ed5n \u00e1p sau (LDO ho\u1eb7c LC) thay v\u00ec ch\u1ec9 d\u1ef1a v\u00e0o c\u00e1c th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt<\/td><\/tr>\n <\/tbody>\n <\/table>\n <\/div>\n\n <p>M\u1ed9t l\u01b0u \u00fd v\u1ec1 t\u00ednh trung th\u1ef1c: kh\u00f4ng c\u00f3 ng\u01b0\u1ee1ng chung ch\u00ednh th\u1ee9c n\u00e0o cho c\u00e1c d\u1ea3i n\u00e0y, b\u1edfi v\u00ec b\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u1ee7a t\u1eebng l\u00f4 h\u00e0ng m\u1edbi l\u00e0 ngu\u1ed3n tham kh\u1ea3o ch\u00ednh x\u00e1c nh\u1ea5t; do \u0111\u00f3, b\u1ea3ng ma tr\u1eadn ch\u1ec9 gi\u00fap b\u1ea1n x\u00e1c \u0111\u1ecbnh v\u1ecb tr\u00ed c\u1ea7n xem x\u00e9t, ch\u1ee9 kh\u00f4ng ph\u1ea3i l\u00e0 m\u1ed9t con s\u1ed1 \u0111\u1ec3 tin t\u01b0\u1edfng m\u00f9 qu\u00e1ng. V\u00e0 h\u00e3y nh\u1edb r\u1eb1ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt th\u01b0\u1eddng kh\u00f4ng \u0111\u1ec1 c\u1eadp \u0111\u1ebfn y\u1ebfu t\u1ed1 l\u00e3o h\u00f3a. Khi c\u00e1c t\u1ee5 \u0111i\u1ec7n \u0111\u1ea7u ra l\u00e3o h\u00f3a, gi\u00e1 tr\u1ecb ESR s\u1ebd t\u0103ng l\u00ean v\u00e0 kh\u1ea3 n\u0103ng l\u1ecdc suy gi\u1ea3m; do \u0111\u00f3, m\u1ed9t ngu\u1ed3n \u0111i\u1ec7n \u0111\u00e3 \u0111\u1ea1t ti\u00eau chu\u1ea9n v\u00e0o n\u0103m \u0111\u1ea7u ti\u00ean c\u00f3 th\u1ec3 tr\u1edf n\u00ean \u1ed3n \u00e0o h\u01a1n v\u00e0o n\u0103m th\u1ee9 n\u0103m. H\u00e3y g\u1ecdi \u0111\u00f3 l\u00e0 ch\u1ebf \u0111\u1ed9 h\u1ecfng h\u00f3c \u201ctr\u01b0\u1edbc \u0111\u00e2y v\u1eabn \u1ed5n\u201d.<\/p>\n\n <h2>\u0110\u1ecdc t\u00e0i li\u1ec7u k\u1ef9 thu\u1eadt Ripple: Nh\u1eefng \u0111i\u1ec1u m\u00e0 c\u00e1c s\u1ed1 li\u1ec7u trong b\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt cho bi\u1ebft v\u00e0 kh\u00f4ng cho bi\u1ebft<\/h2>\n\n <p>M\u1ed9t th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt nh\u01b0 \u201cDao \u0111\u1ed9ng v\u00e0 nhi\u1ec5u: 120 mVp-p\u201d c\u00f3 v\u1ebb t\u01b0\u01a1ng \u0111\u01b0\u01a1ng gi\u1eefa c\u00e1c nh\u00e0 cung c\u1ea5p. Tuy nhi\u00ean, th\u1ef1c t\u1ebf kh\u00f4ng ph\u1ea3i v\u1eady, cho \u0111\u1ebfn khi b\u1ea1n n\u1eafm r\u00f5 c\u00e1c \u0111i\u1ec1u ki\u1ec7n c\u1ee5 th\u1ec3.<\/p>\n\n <h3>H\u00ecnh \u1ea3nh n\u00e0y l\u00e0 \u1ea3nh ch\u1ee5p m\u1ed9t thi\u1ebft l\u1eadp th\u1eed nghi\u1ec7m<\/h3>\n\n <p>H\u00e3y l\u1ea5y m\u1ed9t d\u00f2ng s\u1ea3n ph\u1ea9m ngu\u1ed3n \u0111i\u1ec7n 75 W g\u1eafn tr\u00ean thanh DIN ph\u1ed5 bi\u1ebfn l\u00e0m v\u00ed d\u1ee5: d\u00f2ng Mean Well NDR-75 ghi r\u00f5 m\u1ee9c dao \u0111\u1ed9ng 80 mVp-p \u1edf \u0111i\u1ec7n \u00e1p \u0111\u1ea7u ra 12 V, 120 mVp-p \u1edf 24 V, v\u00e0 150 mVp-p \u1edf m\u1ee9c 48 V. \u0110i\u1ec1u m\u00e0 b\u1ea3ng th\u00f4ng s\u1ed1 c\u1ee7a nh\u00e0 ph\u00e2n ph\u1ed1i kh\u00f4ng th\u1ec3 hi\u1ec7n, v\u00e0 th\u01b0\u1eddng \u0111\u01b0\u1ee3c ghi r\u00f5 b\u1eb1ng ch\u1eef nh\u1ecf trong b\u1ea3ng d\u1eef li\u1ec7u \u0111\u1ea7y \u0111\u1ee7, ch\u00ednh l\u00e0 ph\u01b0\u01a1ng ph\u00e1p \u0111o l\u01b0\u1eddng: d\u1ea3i t\u1ea7n (th\u01b0\u1eddng l\u00e0 20 MHz), \u0111i\u1ec1u ki\u1ec7n t\u1ea3i (th\u01b0\u1eddng l\u00e0 t\u1ea3i \u0111\u1ea7y \u0111\u1ee7), v\u00e0 ph\u01b0\u01a1ng ph\u00e1p k\u1ebft th\u00fac (k\u1ef9 thu\u1eadt c\u00e1p \u0111\u1ed3ng tr\u1ee5c 50 \u03a9 trong t\u00e0i li\u1ec7u h\u01b0\u1edbng d\u1eabn \u1ee9ng d\u1ee5ng c\u1ee7a Analog Devices, <a href=\"https:\/\/www.analog.com\/en\/resources\/app-notes\/an-1144.html\" target=\"_blank\" rel=\"noopener\">M\u1ed9t ngh\u00ecn m\u1ed9t tr\u0103m b\u1ed1n m\u01b0\u01a1i b\u1ed1n<\/a>). Hai b\u1ed9 ngu\u1ed3n \u0111\u1ec1u c\u00f3 th\u1ec3 kh\u1eb3ng \u0111\u1ecbnh m\u1ed9t c\u00e1ch ch\u00ednh x\u00e1c r\u1eb1ng ch\u00fang c\u00f3 \u201c120 mVp-p\u201d nh\u01b0ng l\u1ea1i ho\u1ea1t \u0111\u1ed9ng kh\u00e1c nhau khi ch\u1ecbu d\u00f2ng t\u1ea3i, b\u1edfi v\u00ec m\u1ed9t b\u1ed9 \u0111\u01b0\u1ee3c \u0111o \u1edf t\u1ea3i 50% c\u00f2n b\u1ed9 kia \u1edf t\u1ea3i 100%, ho\u1eb7c m\u1ed9t b\u1ed9 ho\u1ea1t \u0111\u1ed9ng \u1edf t\u1ea7n s\u1ed1 20 MHz c\u00f2n b\u1ed9 kia ho\u1ea1t \u0111\u1ed9ng \u1edf ch\u1ebf \u0111\u1ed9 m\u1edf r\u1ed9ng t\u1ed1i \u0111a.<\/p>\n\n \n <div class=\"bp-specnote-card\">\n <div class=\"bp-specnote-cells\">\n <div class=\"bp-specnote-cell\">\n <p class=\"bp-specnote-label\">typ<\/p>\n <p class=\"bp-specnote-text\">M\u1ed9t m\u1eabu th\u1eed th\u1eadt tuy\u1ec7t v\u1eddi v\u00e0o m\u1ed9t ng\u00e0y \u0111\u1eb9p tr\u1eddi.<\/p>\n <\/div>\n <div class=\"bp-specnote-cell\">\n <p class=\"bp-specnote-label\">v\u01b0\u1ee3t qu\u00e1<\/p>\n <p class=\"bp-specnote-text\">Cam k\u1ebft m\u00e0 b\u1ea1n c\u00f3 th\u1ec3 y\u00eau c\u1ea7u nh\u00e0 cung c\u1ea5p ph\u1ea3i tu\u00e2n th\u1ee7.<\/p>\n <\/div>\n <\/div>\n <p class=\"bp-specnote-foot\">Ch\u1ec9 in c\u00e1c gi\u00e1 tr\u1ecb \u0111i\u1ec3n h\u00ecnh th\u00f4i sao? Kh\u00f4ng c\u00f3 g\u00ec \u0111\u01b0\u1ee3c \u0111\u1ea3m b\u1ea3o c\u1ea3.<\/p>\n <\/div>\n\n <h3>\u0110i\u1ec3m kh\u00e1c bi\u1ec7t th\u1ef1c s\u1ef1 gi\u1eefa c\u00e1c m\u1eb7t h\u00e0ng gi\u00e1 r\u1ebb v\u00e0 cao c\u1ea5p<\/h3>\n\n <p>\u0110\u00e2y l\u00e0 xu h\u01b0\u1edbng \u0111\u00e1ng l\u01b0u \u00fd: v\u1ec1 \u0111\u1ed9 g\u1ee3n dao \u0111\u1ed9ng c\u01a1 b\u1ea3n, c\u00e1c b\u1ed9 ngu\u1ed3n gi\u00e1 r\u1ebb v\u00e0 th\u01b0\u01a1ng hi\u1ec7u n\u1ed5i ti\u1ebfng c\u00f9ng ph\u00e2n kh\u00fac \u0111\u1ec1u n\u1eb1m trong c\u00f9ng m\u1ed9t kho\u1ea3ng gi\u00e1 tr\u1ecb t\u00ednh b\u1eb1ng mili-v\u00f4n: m\u1ee9c 80 \u0111\u1ebfn 150 mVp-p tr\u00ean c\u00e1c \u0111\u01b0\u1eddng ngu\u1ed3n 12\u201348 V l\u00e0 ph\u1ed5 bi\u1ebfn tr\u00ean th\u1ecb tr\u01b0\u1eddng. S\u1ef1 ch\u00eanh l\u1ec7ch xu\u1ea5t hi\u1ec7n \u1edf ba t\u00edn hi\u1ec7u c\u00f2n l\u1ea1i. C\u00e1c \u0111\u1ec9nh nhi\u1ec5u kh\u00f4ng \u0111\u01b0\u1ee3c quy \u0111\u1ecbnh (ho\u1eb7c b\u1ecb lo\u1ea1i tr\u1eeb b\u1eb1ng c\u00e1c gi\u1edbi h\u1ea1n b\u0103ng th\u00f4ng); ph\u1ea3n \u1ee9ng qu\u00e1 \u0111\u1ed9 kh\u00f4ng n\u1eb1m trong h\u00e0ng dao \u0111\u1ed9ng; v\u00e0 t\u00ednh minh b\u1ea1ch v\u1ec1 \u0111i\u1ec1u ki\u1ec7n (li\u1ec7u nh\u00e0 cung c\u1ea5p c\u00f3 ti\u1ebft l\u1ed9 c\u00f4ng th\u1ee9c s\u1ea3n xu\u1ea5t hay kh\u00f4ng) r\u1ea5t \u0111a d\u1ea1ng. V\u00ec v\u1eady, khi s\u1ef1 ch\u00eanh l\u1ec7ch gi\u00e1 mang l\u1ea1i gi\u00e1 tr\u1ecb th\u1ef1c s\u1ef1, \u0111\u00f3 th\u01b0\u1eddng l\u00e0 s\u1ef1 kh\u00e1c bi\u1ec7t gi\u1eefa ti\u00eau chu\u1ea9n \"t\u1ed1i \u0111a\" v\u00e0 \"\u0111i\u1ec3n h\u00ecnh\", t\u00ednh nh\u1ea5t qu\u00e1n gi\u1eefa c\u00e1c l\u00f4 h\u00e0ng, \u0111i\u1ec1u ki\u1ec7n th\u1eed nghi\u1ec7m trung th\u1ef1c, v\u00e0 ch\u1ebf \u0111\u1ed9 b\u1ea3o h\u00e0nh \u0111i k\u00e8m v\u1edbi con s\u1ed1 \u0111\u00f3, ch\u1ee9 kh\u00f4ng ph\u1ea3i l\u00e0 con s\u1ed1 dao \u0111\u1ed9ng th\u1ea5p h\u01a1n.<\/p>\n\n <h3>N\u0103m c\u00e2u h\u1ecfi c\u1ea7n \u0111\u1eb7t ra cho b\u1ea5t k\u1ef3 nh\u00e0 cung c\u1ea5p b\u1ed9 ngu\u1ed3n n\u00e0o<\/h3>\n\n \n <div class=\"rich-checklist\">\n <p class=\"rich-checklist-title\"><span class=\"rich-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"m3 17 2 2 4-4\"\/><path d=\"m3 7 2 2 4-4\"\/><path d=\"M13 6h8\"\/><path d=\"M13 12h8\"\/><path d=\"M13 18h8\"\/><\/svg><\/span>N\u0103m c\u00e2u h\u1ecfi c\u1ea7n l\u01b0u \u00fd tr\u01b0\u1edbc khi so s\u00e1nh c\u00e1c th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u1ee7a Ripple<\/p>\n <ul class=\"rich-checklist-list\">\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>\u0110\u00e2y l\u00e0 typ hay max?<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>N\u00f3 \u0111\u01b0\u1ee3c \u0111o \u1edf b\u0103ng th\u00f4ng n\u00e0o (20 MHz hay b\u0103ng th\u00f4ng m\u1edf)?<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>\u1ede m\u1ee9c t\u1ea3i n\u00e0o (\u0111\u1ea7y, m\u1ed9t n\u1eeda hay kh\u00f4ng x\u00e1c \u0111\u1ecbnh)?<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>C\u00f3 ti\u00eau chu\u1ea9n ri\u00eang v\u1ec1 nhi\u1ec5u kh\u00f4ng, hay \u201c\u0111\u1ed9 dao \u0111\u1ed9ng v\u00e0 nhi\u1ec5u\u201d \u0111\u01b0\u1ee3c g\u1ed9p chung l\u1ea1i v\u1edbi nhau?<\/li>\n <li><span class=\"rich-item-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M20 6 9 17l-5-5\"\/><\/svg><\/span>Khi t\u1ea3i th\u1ef1c t\u1ebf thay \u0111\u1ed5i theo t\u1eebng b\u01b0\u1edbc th\u00ec t\u00edn hi\u1ec7u \u0111\u1ea7u ra s\u1ebd nh\u01b0 th\u1ebf n\u00e0o, v\u00e0 c\u00f3 th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt v\u1ec1 hi\u1ec7n t\u01b0\u1ee3ng qu\u00e1 \u0111\u1ed9 kh\u00f4ng?<\/li>\n <\/ul>\n <\/div>\n\n <p>V\u00e0 ranh gi\u1edbi m\u00e0 ch\u1eb3ng ai in ra: <strong>khi vi\u1ec7c l\u1ecdc d\u1eef li\u1ec7u kh\u00f4ng th\u1ec3 kh\u1eafc ph\u1ee5c \u0111\u01b0\u1ee3c v\u1ea5n \u0111\u1ec1.<\/strong> N\u1ebfu b\u1ea1n \u0111\u00e3 th\u1eed s\u1eed d\u1ee5ng t\u1ee5 \u0111i\u1ec7n \u0111\u1ea7u ra m\u00e0 m\u1ee9c \u201cripple\u201d v\u1eabn cao, th\u00ec g\u1ea7n nh\u01b0 ch\u1eafc ch\u1eafn l\u00e0 b\u1ea1n \u0111ang x\u1eed l\u00fd c\u00e1c \u0111\u1ec9nh nhi\u1ec5u, ch\u1ee9 kh\u00f4ng ph\u1ea3i ripple. C\u00e1c t\u1ee5 \u0111i\u1ec7n \u1edf \u0111\u1ea7u ra c\u00f3 th\u1ec3 l\u00e0m m\u1ecbn th\u00e0nh ph\u1ea7n \u0111\u1ecbnh k\u1ef3 nh\u01b0ng s\u1ebd kh\u00f4ng lo\u1ea1i b\u1ecf \u0111\u01b0\u1ee3c c\u00e1c \u0111\u1ec9nh nhi\u1ec5u c\u00f3 d\u1ea3i t\u1ea7n tr\u00f9ng l\u1eb7p v\u1edbi t\u00edn hi\u1ec7u chuy\u1ec3n m\u1ea1ch (<a href=\"https:\/\/electronics.stackexchange.com\/questions\/707711\/switching-power-supply-has-high-ripple-voltage-no-matter-how-many-capacitors-are\" target=\"_blank\" rel=\"noopener\">StackExchange v\u1ec1 \u0110i\u1ec7n t\u1eed<\/a>, 2024). \u0110\u1ed1i v\u1edbi c\u00e1c t\u1ea3i y\u00eau c\u1ea7u \u0111\u1ed9 ch\u00ednh x\u00e1c cao, c\u00e2u tr\u1ea3 l\u1eddi trung th\u1ef1c th\u01b0\u1eddng l\u00e0 s\u1eed d\u1ee5ng b\u1ed9 \u0111i\u1ec1u ch\u1ec9nh sau (m\u1ed9t b\u1ed9 l\u1ecdc LC ho\u1eb7c b\u1ed9 \u0111i\u1ec1u ch\u1ec9nh \u0111i\u1ec7n \u00e1p tuy\u1ebfn t\u00ednh LDO \u0111\u1eb7t sau b\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch) thay v\u00ec m\u1ed9t b\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch \u0111\u1eaft ti\u1ec1n h\u01a1n v\u1edbi th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt \u1ea5n t\u01b0\u1ee3ng h\u01a1n.<\/p>\n\n <h2>Kh\u1eafc ph\u1ee5c s\u1ef1 c\u1ed1 t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng: Ngu\u1ed3n 24 V \u201cb\u1ecb nhi\u1ec5u\u201d \u0111\u00e3 l\u00e0m h\u1ecfng c\u1ea3m bi\u1ebfn c\u1ee7a t\u00f4i \u2014 \u0110\u00f3 c\u00f3 ph\u1ea3i l\u00e0 hi\u1ec7n t\u01b0\u1ee3ng g\u1ee3n s\u00f3ng hay kh\u00f4ng?<\/h2>\n\n <p>Khi m\u1ed9t b\u1ed9 truy\u1ec1n t\u00edn hi\u1ec7u 4\u201320 mA li\u00ean t\u1ee5c b\u1ecb ch\u00e1y ho\u1eb7c gi\u00e1 tr\u1ecb \u0111o analog b\u1ecb l\u1ec7ch, ph\u1ea3n \u1ee9ng b\u1ea3n n\u0103ng c\u1ee7a ng\u01b0\u1eddi l\u00e0m vi\u1ec7c t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng l\u00e0 ho\u00e0n to\u00e0n \u0111\u00fang: h\u00e3y nghi ng\u1edd ngu\u1ed3n \u0111i\u1ec7n tr\u01b0\u1edbc ti\u00ean. \u201c\u0110i\u1ec1u \u0111\u1ea7u ti\u00ean t\u00f4i s\u1ebd ki\u1ec3m tra l\u00e0 ngu\u1ed3n \u0111i\u1ec7n \u2014 \u0111\u1ea3m b\u1ea3o \u0111\u00f3 l\u00e0 ngu\u1ed3n 24 VDC s\u1ea1ch v\u00e0 \u1ed5n \u0111\u1ecbnh, kh\u00f4ng c\u00f3 \u0111\u1ed9t bi\u1ebfn hay nhi\u1ec5u; ngu\u1ed3n \u0111i\u1ec7n kh\u00f4ng \u1ed5n \u0111\u1ecbnh c\u00f3 th\u1ec3 l\u00e0m h\u1ecfng c\u1ea3m bi\u1ebfn r\u1ea5t nhanh,\u201d nh\u01b0 m\u1ed9t k\u1ef9 thu\u1eadt vi\u00ean tr\u00ean di\u1ec5n \u0111\u00e0n r\/PLC \u0111\u00e3 chia s\u1ebb khi ch\u1ea9n \u0111o\u00e1n m\u1ed9t b\u1ed9 truy\u1ec1n t\u00edn hi\u1ec7u \u00e1p su\u1ea5t \u0111\u00e3 l\u00e0m h\u1ecfng hai b\u1ed9 thay th\u1ebf ch\u1ec9 trong v\u00e0i ng\u00e0y (<a href=\"https:\/\/www.reddit.com\/r\/PLC\/comments\/1kragst\/420_ma_pressure_transmitter_help\/\" target=\"_blank\" rel=\"noopener\">Reddit r\/PLC<\/a>, 2025). Nh\u01b0ng h\u00e3y l\u01b0u \u00fd nh\u1eefng y\u1ebfu t\u1ed1 m\u00e0 danh s\u00e1ch ki\u1ec3m tra trong ch\u1ee7 \u0111\u1ec1 \u0111\u00f3 th\u1ef1c s\u1ef1 nh\u1eafm \u0111\u1ebfn: c\u00e1c \u0111\u1ec9nh \u0111i\u1ec7n \u00e1p khi c\u00f4ng t\u1eafc t\u01a1 v\u00e0 \u0111\u1ed9ng c\u01a1 kh\u1edfi \u0111\u1ed9ng, n\u1ed1i \u0111\u1ea5t v\u00e0 li\u00ean k\u1ebft, r\u00f2 r\u1ec9 t\u1eeb b\u1ed9 bi\u1ebfn t\u1ea7n (VFD), ch\u1ee9 kh\u00f4ng ph\u1ea3i th\u00f4ng s\u1ed1 g\u1ee3n s\u00f3ng. \u0110\u00f3 ch\u00ednh l\u00e0 s\u1ef1 ph\u00e2n bi\u1ec7t b\u1ed1n t\u00edn hi\u1ec7u \u0111ang \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng trong th\u1ef1c t\u1ebf.<\/p>\n\n <ol>\n <li><strong>X\u00e1c \u0111\u1ecbnh ph\u1ea1m vi c\u1ee7a \u0111\u01b0\u1eddng ray qua c\u00e1c s\u1ef1 ki\u1ec7n chuy\u1ec3n m\u1ea1ch:<\/strong> H\u00e3y xem x\u00e9t nh\u1eefng g\u00ec x\u1ea3y ra ngay l\u1eadp t\u1ee9c khi m\u1ed9t r\u01a1le ho\u1eb7c \u0111\u1ed9ng c\u01a1 trong t\u1ee7 \u0111i\u1ec7n ho\u1ea1t \u0111\u1ed9ng, ch\u1ee9 kh\u00f4ng ch\u1ec9 d\u1ef1a v\u00e0o d\u1ea1ng s\u00f3ng \u1ed5n \u0111\u1ecbnh.<\/li>\n <li><strong>Ki\u1ec3m tra \u0111i\u1ec7n \u00e1p tham chi\u1ebfu 0 V:<\/strong> Li\u1ec7u c\u1ef1c \u00e2m c\u1ee7a ngu\u1ed3n c\u00f3 \u0111\u01b0\u1ee3c n\u1ed1i v\u1edbi m\u1ed9t \u0111i\u1ec3m n\u1ed1i \u0111\u1ea5t \u0111ang d\u1eabn d\u00f2ng \u0111i\u1ec7n t\u1eeb c\u00e1c thi\u1ebft b\u1ecb kh\u00e1c kh\u00f4ng? Gi\u00e1 tr\u1ecb \u201c0 V\u201d thay \u0111\u1ed5i khi c\u00f3 t\u1ea3i l\u00e0 do v\u1ea5n \u0111\u1ec1 ti\u00eam d\u00f2ng, ch\u1ee9 kh\u00f4ng ph\u1ea3i do v\u1ea5n \u0111\u1ec1 dao \u0111\u1ed9ng.<\/li>\n <li><strong>H\u00e3y ch\u00fa \u00fd \u0111\u1ebfn c\u00e1c ngu\u1ed3n b\u00ean ngo\u00e0i:<\/strong> \u0110\u1ed9ng c\u01a1 \u0111i\u1ec1u khi\u1ec3n b\u1eb1ng bi\u1ebfn t\u1ea7n (VFD), ho\u1ea1t \u0111\u1ed9ng h\u00e0n g\u1ea7n \u0111\u00f3, \u0111i\u1ec3m n\u1ed1i \u0111\u1ea5t b\u1ecb \u0103n m\u00f2n tr\u00ean d\u00e2y chuy\u1ec1n s\u1ea3n xu\u1ea5t. M\u1ed9t tr\u01b0\u1eddng h\u1ee3p li\u00ean quan \u0111\u1ebfn r\/PLC \u0111\u00e3 x\u00e1c \u0111\u1ecbnh nguy\u00ean nh\u00e2n khi\u1ebfn c\u00e1c c\u1ea3m bi\u1ebfn li\u00ean t\u1ee5c h\u1ecfng l\u00e0 do \u0111i\u1ec3m n\u1ed1i \u0111\u1ea5t b\u1ecb \u0103n m\u00f2n tr\u00ean \u0111\u1ed9ng c\u01a1 b\u01a1m \u0111i\u1ec1u khi\u1ec3n b\u1eb1ng bi\u1ebfn t\u1ea7n (VFD), v\u1ed1n \u0111\u01b0\u1ee3c k\u1ebft n\u1ed1i v\u1eadt l\u00fd v\u1edbi c\u00f9ng m\u1ed9t b\u1ec3 ch\u1ee9a (<a href=\"https:\/\/www.reddit.com\/r\/PLC\/comments\/1kragst\/420_ma_pressure_transmitter_help\/\" target=\"_blank\" rel=\"noopener\">Reddit r\/PLC<\/a>, 2025).<\/li>\n <li><strong>Ti\u1ebfn h\u00e0nh th\u00ed nghi\u1ec7m c\u00e1ch ly:<\/strong> C\u1ea5p ngu\u1ed3n cho c\u1ea3m bi\u1ebfn nghi ng\u1edd t\u1eeb m\u1ed9t ngu\u1ed3n \u0111i\u1ec7n ri\u00eang bi\u1ec7t, d\u00e0nh ri\u00eang cho m\u1ee5c \u0111\u00edch n\u00e0y (ho\u1eb7c th\u00f4ng qua b\u1ed9 c\u00e1ch ly t\u00edn hi\u1ec7u). N\u1ebfu c\u1ea3m bi\u1ebfn v\u1eabn ho\u1ea1t \u0111\u1ed9ng b\u00ecnh th\u01b0\u1eddng \u1edf \u0111\u00f3, th\u00ec ngu\u1ed3n \u0111i\u1ec7n kh\u00f4ng ph\u1ea3i l\u00e0 nguy\u00ean nh\u00e2n g\u00e2y ra s\u1ef1 c\u1ed1; n\u1ebfu c\u1ea3m bi\u1ebfn c\u0169ng ng\u1eebng ho\u1ea1t \u0111\u1ed9ng \u1edf \u0111\u00f3, h\u00e3y ki\u1ec3m tra c\u1ea3m bi\u1ebfn v\u00e0 m\u1ea1ch \u0111i\u1ec1u khi\u1ec3n.<\/li>\n <\/ol>\n\n \n <div class=\"rich-steps\">\n <p class=\"rich-steps-title\"><span class=\"rich-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><circle cx=\"6\" cy=\"19\" r=\"3\"\/><path d=\"M9 19h8.5a3.5 3.5 0 0 0 0-7h-11a3.5 3.5 0 0 1 0-7H15\"\/><circle cx=\"18\" cy=\"5\" r=\"3\"\/><\/svg><\/span>Ph\u00e2n lo\u1ea1i t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng: c\u00f3 hi\u1ec7n t\u01b0\u1ee3ng g\u1ee3n s\u00f3ng hay kh\u00f4ng?<\/p>\n <ol class=\"rich-steps-list\">\n <li><span class=\"rich-step-num\">1<\/span>Xem x\u00e9t trong to\u00e0n b\u1ed9 qu\u00e1 tr\u00ecnh chuy\u1ec3n m\u1ea1ch, kh\u00f4ng ch\u1ec9 \u1edf tr\u1ea1ng th\u00e1i \u1ed5n \u0111\u1ecbnh<\/li>\n <li><span class=\"rich-step-num\">2<\/span>Ki\u1ec3m tra xem \u0111i\u1ec7n \u00e1p tham chi\u1ebfu 0 V c\u00f3 b\u1ecb dao \u0111\u1ed9ng theo c\u00e1c t\u1ea3i kh\u00e1c hay kh\u00f4ng<\/li>\n <li><span class=\"rich-step-num\">3<\/span>T\u00ecm ki\u1ebfm c\u00e1c ngu\u1ed3n g\u00e2y r\u00f2 r\u1ec9 b\u00ean ngo\u00e0i (bi\u1ebfn t\u1ea7n, m\u1ed1i h\u00e0n, c\u00e1c \u0111i\u1ec3m n\u1ed1i b\u1ecb \u0103n m\u00f2n)<\/li>\n <li><span class=\"rich-step-num\">4<\/span>H\u00e3y t\u00e1ch ri\u00eang c\u1ea3m bi\u1ebfn ra kh\u1ecfi ngu\u1ed3n \u0111i\u1ec7n chuy\u00ean d\u1ee5ng v\u00e0 theo d\u00f5i<\/li>\n <\/ol>\n <\/div>\n\n <p>Ng\u01b0\u1ee3c l\u1ea1i, ranh gi\u1edbi n\u00e0y c\u0169ng c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c hi\u1ec3u theo h\u01b0\u1edbng kh\u00e1c: r\u1ea5t nhi\u1ec1u c\u1ea3m bi\u1ebfn h\u1ecfng ho\u00e0n to\u00e0n kh\u00f4ng li\u00ean quan \u0111\u1ebfn b\u1ed9 ngu\u1ed3n. C\u00e1c v\u00f2ng l\u1eb7p \u0111\u1ea5t, hi\u1ec7n t\u01b0\u1ee3ng r\u00f2 r\u1ec9 ch\u1ebf \u0111\u1ed9 chung c\u1ee7a bi\u1ebfn t\u1ea7n (VFD), vi\u1ec7c h\u00e0n trong khi h\u1ec7 th\u1ed1ng \u0111ang t\u1eaft m\u00e1y, v\u00e0 ch\u00ednh c\u1ea3m bi\u1ebfn \u0111\u00f3 \u0111\u1ec1u ng\u1ee5y trang d\u01b0\u1edbi d\u1ea1ng \u201cngu\u1ed3n \u0111i\u1ec7n b\u1ea9n\u201d. B\u1ed1n b\u01b0\u1edbc n\u00e0y t\u1ed3n t\u1ea1i ch\u00ednh x\u00e1c \u0111\u1ec3 ng\u0103n b\u1ea1n thay th\u1ebf m\u1ed9t b\u1ed9 ngu\u1ed3n c\u00f2n t\u1ed1t b\u1eb1ng m\u1ed9t b\u1ed9 ngu\u1ed3n t\u1ed1t h\u01a1n r\u1ed3i cho r\u1eb1ng c\u00f4ng vi\u1ec7c \u0111\u00e3 ho\u00e0n t\u1ea5t. \u0110\u00f3 ch\u00ednh l\u00e0 tr\u01b0\u1eddng h\u1ee3p \u0111i\u1ec3n h\u00ecnh c\u1ee7a vi\u1ec7c \u201cs\u1eeda ch\u1eefa\u201d t\u1ed1n k\u00e9m nh\u01b0ng kh\u00f4ng gi\u1ea3i quy\u1ebft \u0111\u01b0\u1ee3c v\u1ea5n \u0111\u1ec1.<\/p>\n\n <h2>D\u00e0nh cho c\u00e1c nh\u00e0 ph\u00e2n ph\u1ed1i: H\u00e3y b\u00e1n d\u1ecbch v\u1ee5 ch\u1ea9n \u0111o\u00e1n, ch\u1ee9 kh\u00f4ng ph\u1ea3i m\u1ee9c \u0111i\u1ec7n \u00e1p millivolt th\u1ea5p nh\u1ea5t<\/h2>\n\n <p>N\u1ebfu b\u1ea1n kinh doanh b\u1ed9 ngu\u1ed3n, t\u1ea5t c\u1ea3 nh\u1eefng \u0111i\u1ec1u n\u00eau tr\u00ean \u0111\u1ec1u c\u00f3 th\u1ec3 t\u00f3m g\u1ecdn th\u00e0nh m\u1ed9t th\u1ef1c t\u1ebf th\u01b0\u01a1ng m\u1ea1i: kh\u00e1ch h\u00e0ng g\u1ecdi \u0111i\u1ec7n than phi\u1ec1n v\u1ec1 c\u1ea3m bi\u1ebfn b\u1ecb ch\u00e1y ho\u1eb7c v\u00f2ng \u0111i\u1ec1u khi\u1ec3n b\u1ecb l\u1ec7ch kh\u00f4ng ph\u1ea3i \u0111ang h\u1ecfi b\u1ed9 ngu\u1ed3n n\u00e0o c\u00f3 ch\u1ec9 s\u1ed1 g\u1ee3n s\u00f3ng th\u1ea5p nh\u1ea5t. H\u1ecd \u0111ang h\u1ecfi li\u1ec7u b\u1ed9 ngu\u1ed3n h\u1ecd \u0111ang d\u00f9ng c\u00f3 ph\u1ea3i l\u00e0 nguy\u00ean nh\u00e2n g\u00e2y ra s\u1ef1 c\u1ed1 hay kh\u00f4ng, v\u00e0 n\u00ean mua s\u1ea3n ph\u1ea9m n\u00e0o thay th\u1ebf. C\u00e1c linh ki\u1ec7n m\u00e0 b\u1ea1n b\u00e1n li\u00ean quan \u0111\u1ebfn c\u1ea3 hai kh\u00eda c\u1ea1nh c\u1ee7a c\u00e2u h\u1ecfi \u0111\u00f3.<\/p>\n\n <p>V\u00ec v\u1eady, logic b\u00e1n h\u00e0ng ph\u1ea3i tu\u00e2n theo logic k\u1ef9 thu\u1eadt. \u0110\u1ed1i v\u1edbi c\u00e1c t\u1ea3i thu\u1ed9c lo\u1ea1i mi\u1ec5n nhi\u1ec5m (r\u01a1le, \u0111\u00e8n, t\u1ee7 ti\u1ebfp \u0111i\u1ec3m \u2013 chi\u1ebfm ph\u1ea7n l\u1edbn th\u1ecb tr\u01b0\u1eddng s\u1eeda ch\u1eefa v\u00e0 b\u1ea3o tr\u00ec), \u0111\u1ed9 g\u1ee3n kh\u00f4ng ph\u1ea3i l\u00e0 \u0111i\u1ec3m b\u00e1n h\u00e0ng. H\u00e3y c\u1ea1nh tranh v\u1ec1 gi\u00e1 c\u1ea3, t\u00ednh s\u1eb5n c\u00f3 v\u00e0 \u0111\u1ed9 b\u1ec1n, v\u00e0 \u0111\u1eebng l\u00e3ng ph\u00ed c\u00e1c b\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt ch\u1ea5t l\u01b0\u1ee3ng cao cho nh\u1eefng kh\u00e1ch h\u00e0ng s\u1ebd kh\u00f4ng bao gi\u1edd nh\u1eadn ra s\u1ef1 kh\u00e1c bi\u1ec7t. \u0110\u1ed1i v\u1edbi c\u00e1c t\u1ea3i nh\u1ea1y c\u1ea3m (v\u00f2ng l\u1eb7p 4\u201320 mA, b\u1ed9 truy\u1ec1n t\u00edn hi\u1ec7u, th\u1ebb analog, b\u1ed9 m\u00e3 h\u00f3a), h\u00e3y b\u00e1n s\u1ef1 minh b\u1ea1ch v\u1ec1 th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt thay v\u00ec gi\u00e1 tr\u1ecb millivolt th\u1ea5p nh\u1ea5t. Cung c\u1ea5p gi\u00e1 tr\u1ecb t\u1ed1i \u0111a (ch\u1ee9 kh\u00f4ng ph\u1ea3i gi\u00e1 tr\u1ecb \u0111i\u1ec3n h\u00ecnh), b\u0103ng th\u00f4ng \u0111\u01b0\u1ee3c \u0111o v\u00e0 \u0111i\u1ec1u ki\u1ec7n t\u1ea3i; gi\u1ea3i th\u00edch nh\u1eefng g\u00ec con s\u1ed1 \u0111\u00f3 kh\u00f4ng bao g\u1ed3m (nhi\u1ec5u, hi\u1ec7n t\u01b0\u1ee3ng qu\u00e1 \u0111\u1ed9). \u0110\u00f3 l\u00e0 s\u1ef1 kh\u00e1c bi\u1ec7t gi\u1eefa m\u1ed9t giao d\u1ecbch h\u00e0ng h\u00f3a th\u00f4ng th\u01b0\u1eddng v\u00e0 m\u1ed9t giao d\u1ecbch t\u01b0 v\u1ea5n, v\u00e0 \u0111\u00f3 l\u00e0 ph\u1ea7n c\u1ee7a cu\u1ed9c tr\u00f2 chuy\u1ec7n m\u00e0 gi\u00e1 ni\u00eam y\u1ebft trong danh m\u1ee5c kh\u00f4ng th\u1ec3 l\u00e0m lu m\u1edd.<\/p>\n\n <p>C\u00f9ng m\u1ed9t logic n\u00e0y c\u0169ng gi\u00fap b\u1ea3o v\u1ec7 d\u1ecbch v\u1ee5 h\u1eadu m\u00e3i c\u1ee7a b\u1ea1n: khi kh\u00e1ch h\u00e0ng b\u00e1o c\u00e1o s\u1ef1 c\u1ed1, h\u00e3y ti\u1ebfn h\u00e0nh ki\u1ec3m tra s\u01a1 b\u1ed9 t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng tr\u01b0\u1edbc khi \u0111\u1ec1 xu\u1ea5t cung c\u1ea5p thi\u1ebft b\u1ecb thay th\u1ebf. M\u1ed9t c\u1ea3m bi\u1ebfn b\u1ecb h\u1ecfng do c\u00e1c \u0111\u1ee3t t\u0103ng \u00e1p \u0111\u1ed9t ng\u1ed9t v\u00e0 hi\u1ec7n t\u01b0\u1ee3ng qu\u00e1 \u00e1p t\u1ea1m th\u1eddi s\u1ebd khi\u1ebfn thi\u1ebft b\u1ecb thay th\u1ebf c\u0169ng b\u1ecb h\u1ecfng theo. C\u00e2u tr\u1ea3 l\u1eddi trung th\u1ef1c ki\u1ec3u \u201cv\u1ea5n \u0111\u1ec1 kh\u00f4ng n\u1eb1m \u1edf b\u1ed9 ngu\u1ed3n, \u0111\u00e2y l\u00e0 nh\u1eefng g\u00ec c\u1ea7n ki\u1ec3m tra\u201d ch\u00ednh l\u00e0 \u0111i\u1ec1u khi\u1ebfn kh\u00e1ch h\u00e0ng mu\u1ed1n li\u00ean h\u1ec7 l\u1ea1i v\u1edbi nh\u00e0 ph\u00e2n ph\u1ed1i. V\u00e0 h\u00e3y nh\u1edb r\u1eb1ng to\u00e0n b\u1ed9 chu\u1ed7i thi\u1ebft b\u1ecb \u0111\u1ec1u n\u1eb1m tr\u00ean c\u00f9ng m\u1ed9t k\u1ec7: b\u1ed9 ngu\u1ed3n, c\u1ea3m bi\u1ebfn v\u00e0 r\u01a1le \u0111i\u1ec1u khi\u1ec3n t\u1ea3i \u0111\u1ec1u thu\u1ed9c c\u00f9ng m\u1ed9t \u0111\u01a1n h\u00e0ng, c\u00f9ng m\u1ed9t t\u1ee7 thi\u1ebft b\u1ecb, v\u00e0 th\u01b0\u1eddng c\u00f3 c\u00f9ng m\u1ed9t ch\u1ea9n \u0111o\u00e1n.<\/p>\n\n \n <div class=\"bp-takeaway-card\">\n <p class=\"bp-takeaway-title\"><span class=\"bp-takeaway-icon\"><svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><circle cx=\"12\" cy=\"12\" r=\"10\"\/><circle cx=\"12\" cy=\"12\" r=\"6\"\/><circle cx=\"12\" cy=\"12\" r=\"2\"\/><\/svg><\/span>Ba quy t\u1eafc<\/p>\n <div class=\"bp-takeaway-rows\">\n <div class=\"bp-takeaway-row\"><span class=\"bp-takeaway-num\">1<\/span><p class=\"bp-takeaway-text\">C\u00e1c y\u1ebfu t\u1ed1 \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn h\u1ec7 mi\u1ec5n d\u1ecbch: gi\u00e1 b\u00e1n, \u0111\u1ed9 b\u1ec1n, t\u00ednh s\u1eb5n c\u00f3.<\/p><\/div>\n <div class=\"bp-takeaway-row\"><span class=\"bp-takeaway-num\">2<\/span><p class=\"bp-takeaway-text\">T\u1ea3i nh\u1ea1y c\u1ea3m: cung c\u1ea5p th\u00f4ng tin v\u1ec1 gi\u00e1 tr\u1ecb t\u1ed1i \u0111a, b\u0103ng th\u00f4ng v\u00e0 c\u00e1c \u0111i\u1ec1u ki\u1ec7n t\u1ea3i.<\/p><\/div>\n <div class=\"bp-takeaway-row\"><span class=\"bp-takeaway-num\">3<\/span><p class=\"bp-takeaway-text\">S\u1ef1 c\u1ed1 t\u1ea1i hi\u1ec7n tr\u01b0\u1eddng: \u01b0u ti\u00ean ki\u1ec3m tra s\u01a1 b\u1ed9 tr\u01b0\u1edbc, thay th\u1ebf sau.<\/p><\/div>\n <\/div>\n <\/div>\n\n <p><em>N\u1ebfu b\u1ea1n c\u1ea7n so s\u00e1nh c\u00e1c b\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch g\u1eafn tr\u00ean thanh DIN trong d\u1ea3i c\u00f4ng su\u1ea5t t\u1eeb 15 W \u0111\u1ebfn 480 W, ho\u1eb7c mu\u1ed1n c\u00f3 ng\u01b0\u1eddi c\u00f9ng b\u1ea1n xem x\u00e9t v\u00e0 l\u1ef1a ch\u1ecdn, OMCH\u2019s <a href=\"https:\/\/www.omch.com\/vi\/switch-mode-power-supply\/\" target=\"_blank\" rel=\"noopener\">D\u00f2ng s\u1ea3n ph\u1ea9m b\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch<\/a> v\u00e0 <a href=\"https:\/\/www.omch.com\/vi\/product-selection\/\" target=\"_blank\" rel=\"noopener\">h\u1ed7 tr\u1ee3 l\u1ef1a ch\u1ecdn s\u1ea3n ph\u1ea9m<\/a> l\u00e0 \u0111i\u1ec3m kh\u1edfi \u0111\u1ea7u thi\u1ebft th\u1ef1c.<\/em><\/p>\n\n \n <div class=\"bp-cta-end\">\n <p class=\"bp-cta-end-title\">C\u00f3 th\u1eafc m\u1eafc v\u1ec1 th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt? H\u00e3y h\u1ecfi tr\u01b0\u1edbc khi mua.<\/p>\n <p class=\"bp-cta-end-sub\">H\u00e3y g\u1eedi cho ch\u00fang t\u00f4i lo\u1ea1i t\u1ea3i v\u00e0 d\u00f2ng \u0111i\u1ec7n ti\u00eau th\u1ee5 c\u1ee7a \u1ee9ng d\u1ee5ng c\u1ee7a b\u1ea1n. C\u00e1c k\u1ef9 s\u01b0 t\u01b0 v\u1ea5n c\u1ee7a ch\u00fang t\u00f4i s\u1ebd \u0111\u1ec1 xu\u1ea5t b\u1ed9 ngu\u1ed3n g\u1eafn tr\u00ean thanh DIN ho\u1eb7c b\u1ed9 ngu\u1ed3n c\u00f3 v\u1ecf b\u1ecdc ph\u00f9 h\u1ee3p v\u00e0 cung c\u1ea5p cho b\u1ea1n c\u00e1c th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt ch\u00ednh x\u00e1c m\u00e0 b\u1ea1n c\u00f3 th\u1ec3 tin c\u1eady.<\/p>\n <a class=\"bp-cta-end-btn\" href=\"https:\/\/www.omch.com\/vi\/contact\/\" target=\"_self\">G\u1eedi y\u00eau c\u1ea7u t\u01b0 v\u1ea5n l\u1ef1a ch\u1ecdn<svg viewbox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M5 12h14\"\/><path d=\"m12 5 7 7-7 7\"\/><\/svg><\/a>\n <\/div>\n\n <p class=\"bd-refs-title\">T\u00e0i li\u1ec7u tham kh\u1ea3o<\/p>\n <ol class=\"bd-refs\">\n <li>Wikipedia. \u201cRipple (\u0111i\u1ec7n).\u201d <a href=\"https:\/\/en.wikipedia.org\/wiki\/Ripple_(electrical)\" target=\"_blank\" rel=\"noopener\">https:\/\/en.wikipedia.org\/wiki\/Ripple_(electrical)<\/a><\/li>\n <li>Analog Devices. \u201cAN-1144: \u0110o dao \u0111\u1ed9ng \u0111\u1ea7u ra v\u00e0 hi\u1ec7n t\u01b0\u1ee3ng chuy\u1ec3n m\u1ea1ch t\u1ea1m th\u1eddi trong b\u1ed9 \u0111i\u1ec1u ch\u1ec9nh chuy\u1ec3n m\u1ea1ch.\u201d <a href=\"https:\/\/www.analog.com\/en\/resources\/app-notes\/an-1144.html\" target=\"_blank\" rel=\"noopener\">https:\/\/www.analog.com\/en\/resources\/app-notes\/an-1144.html<\/a><\/li>\n <li>Tom\u2019s Hardware. \u201c\u0110i\u1ec7n \u00e1p dao \u0111\u1ed9ng \u2014 C\u00e1ch ch\u00fang t\u00f4i ki\u1ec3m tra c\u00e1c b\u1ed9 ngu\u1ed3n.\u201d <a href=\"https:\/\/www.tomshardware.com\/reviews\/how-we-test-psu,4042-5.html\" target=\"_blank\" rel=\"noopener\">https:\/\/www.tomshardware.com\/reviews\/how-we-test-psu,4042-5.html<\/a><\/li>\n <li>Di\u1ec5n \u0111\u00e0n EEVblog. \u201c\u0110o dao \u0111\u1ed9ng ngu\u1ed3n b\u1eb1ng k\u1ef9 thu\u1eadt n\u00e0y.\u201d <a href=\"https:\/\/www.eevblog.com\/forum\/beginners\/measure-power-supply-ripple-with-this-technique\/\" target=\"_blank\" rel=\"noopener\">https:\/\/www.eevblog.com\/forum\/beginners\/measure-power-supply-ripple-with-this-technique\/<\/a><\/li>\n <li>Electronics StackExchange. \u201cB\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch c\u00f3 \u0111i\u1ec7n \u00e1p dao \u0111\u1ed9ng cao b\u1ea5t k\u1ec3 th\u00eam bao nhi\u00eau t\u1ee5 \u0111i\u1ec7n. \u201d <a href=\"https:\/\/electronics.stackexchange.com\/questions\/707711\/\" target=\"_blank\" rel=\"noopener\">https:\/\/electronics.stackexchange.com\/questions\/707711\/<\/a><\/li>\n <li>Electronics StackExchange. \u201cC\u00e1c y\u1ebfu t\u1ed1 c\u1ea7n xem x\u00e9t v\u1ec1 dao \u0111\u1ed9ng \u0111i\u1ec7n \u00e1p \u0111\u1ea7u ra.\u201d <a href=\"https:\/\/electronics.stackexchange.com\/questions\/501187\/\" target=\"_blank\" rel=\"noopener\">https:\/\/electronics.stackexchange.com\/questions\/501187\/<\/a><\/li>\n <li>Reddit r\/PLC. \u201cH\u1ed7 tr\u1ee3 v\u1ec1 b\u1ed9 truy\u1ec1n \u00e1p su\u1ea5t 4\u201320 mA.\u201d <a href=\"https:\/\/www.reddit.com\/r\/PLC\/comments\/1kragst\/420_ma_pressure_transmitter_help\/\" target=\"_blank\" rel=\"noopener\">https:\/\/www.reddit.com\/r\/PLC\/comments\/1kragst\/420_ma_pressure_transmitter_help\/<\/a><\/li>\n <li>Reddit r\/AskElectronics. \u201cM\u1ee9c nhi\u1ec5u\/dao \u0111\u1ed9ng n\u00e0o \u0111\u01b0\u1ee3c ch\u1ea5p nh\u1eadn tr\u00ean c\u00e1c b\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch gi\u00e1 r\u1ebb?\u201d <a href=\"https:\/\/www.reddit.com\/r\/AskElectronics\/comments\/1gm8h7m\/\" target=\"_blank\" rel=\"noopener\">https:\/\/www.reddit.com\/r\/AskElectronics\/comments\/1gm8h7m\/<\/a><\/li>\n <li>WSJT-X Groups.io. \u201cM\u1ee9c dao \u0111\u1ed9ng \u0111i\u1ec7n \u00e1p ngu\u1ed3n PA n\u00e0o \u0111\u01b0\u1ee3c ch\u1ea5p nh\u1eadn?\u201d <a href=\"https:\/\/wsjtx.groups.io\/g\/main\/topic\/acceptable_pa_power_supply\/71775932\" target=\"_blank\" rel=\"noopener\">https:\/\/wsjtx.groups.io\/g\/main\/topic\/acceptable_pa_power_supply\/71775932<\/a><\/li>\n <li>OMCH. \u201cB\u1ed9 ngu\u1ed3n chuy\u1ec3n m\u1ea1ch.\u201d <a href=\"https:\/\/www.omch.com\/vi\/switch-mode-power-supply\/\" target=\"_blank\" rel=\"noopener\">https:\/\/www.omch.com\/switch-mode-power-supply\/<\/a><\/li>\n <li>OMCH. \u201cL\u1ef1a ch\u1ecdn s\u1ea3n ph\u1ea9m.\u201d <a href=\"https:\/\/www.omch.com\/vi\/product-selection\/\" target=\"_blank\" rel=\"noopener\">https:\/\/www.omch.com\/product-selection\/<\/a><\/li>\n <li>OMCH. Trang ch\u1ee7. <a href=\"https:\/\/www.omch.com\/vi\/\" target=\"_blank\" rel=\"noopener\">https:\/\/www.omch.com\/<\/a><\/li>\n <\/ol>\n <\/article>\n<\/div>\n\n<\/body><\/html>","protected":false},"excerpt":{"rendered":"<p>Dao \u0111\u1ed9ng ngu\u1ed3n \u0111i\u1ec7n: N\u00f3 l\u00e0 g\u00ec, c\u00e1ch \u0111o l\u01b0\u1eddng v\u00e0 khi n\u00e0o n\u00f3 quan tr\u1ecdng B\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u1ee7a b\u1ed9 ngu\u1ed3n cho bi\u1ebft dao \u0111\u1ed9ng l\u00e0 \u201c\u2264100 mVp-p.\u201d B\u1ea1n k\u1ebft n\u1ed1i m\u00e1y hi\u1ec7n s\u00f3ng v\u1edbi \u0111\u1ea7u ra v\u00e0 th\u1ea5y d\u1ea1ng s\u00f3ng ho\u00e0n to\u00e0n kh\u00f4ng gi\u1ed1ng v\u1edbi s\u00f3ng r\u0103ng c\u01b0a 100 mV s\u1ea1ch, trong khi m\u1ed9t ng\u01b0\u1eddi \u0111am m\u00ea \u0111i\u1ec7n t\u1eed \u1edf ph\u00f2ng b\u00ean c\u1ea1nh v\u1eeba \u0111o \u0111\u01b0\u1ee3c 1,4 Vp-p \u1edf 5 [\u2026]<\/p>","protected":false},"author":4,"featured_media":12316,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_seopress_robots_primary_cat":"none","_seopress_titles_title":"Power Supply Ripple: What It Is & How to Measure It","_seopress_titles_desc":"Learn what power supply ripple is, how to measure ripple voltage correctly with an oscilloscope, and when ripple matters for different loads.","_seopress_robots_index":"","footnotes":""},"categories":[79],"tags":[],"class_list":["post-12313","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-mmlblog"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/posts\/12313","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/comments?post=12313"}],"version-history":[{"count":1,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/posts\/12313\/revisions"}],"predecessor-version":[{"id":12318,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/posts\/12313\/revisions\/12318"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/media\/12316"}],"wp:attachment":[{"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/media?parent=12313"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/categories?post=12313"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.omch.com\/vi\/wp-json\/wp\/v2\/tags?post=12313"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}