{"id":162138,"date":"2025-05-01T16:09:07","date_gmt":"2025-05-01T10:39:07","guid":{"rendered":"https:\/\/www.electronicsforu.com\/?p=162138"},"modified":"2025-05-06T16:10:31","modified_gmt":"2025-05-06T10:40:31","slug":"pwm-signal-isolation-module","status":"publish","type":"post","link":"https:\/\/www.electronicsforu.com\/electronics-projects\/pwm-signal-isolation-module","title":{"rendered":"Universal PWM Signal Isolation Module"},"content":{"rendered":"<div class=\"wp-block-image\">\n<figure class=\"alignright size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"178\" height=\"169\" src=\"https:\/\/www.electronicsforu.com\/wp-contents\/uploads\/2022\/06\/efy-tested.jpg\" alt=\"efy test\" class=\"wp-image-97958\"\/><\/figure><\/div>\n\n\n<p>This PWM (<a href=\"https:\/\/www.electronicsforu.com\/videos-slideshows\/videos\/introduction-to-pulse-width-modulation-pwm\">pulse width modulation<\/a>) signal isolation module is built around the widely adopted 6N137 high-speed optocoupler. The device combines a high-efficiency input LED with an integrated optical photodiode detector IC to ensure robust signal isolation.<\/p>\n\n\n\n<p>The advanced 6N137 variants incorporate an open drain NMOS transistor output (photodetector logic gate), offering lower leakage than traditional open-collector Schottky-clamped transistor outputs (VO). An integrated enable function (VE) also allows the detector to be strobed, improving design flexibility and control.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">POC Video Tutorial:<\/h2>\n\n\n\n<figure class=\"wp-block-embed aligncenter is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<span class=\"Nr8tYgKdlAQwE2a6fMb\"><iframe loading=\"lazy\" title=\"Universal PWM Signal Isolation Module | Electronics For You\" width=\"696\" height=\"392\" src=\"https:\/\/www.youtube.com\/embed\/buWbj7I62sI?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe><\/span>\n<\/div><\/figure>\n\n\n\n<p>Optocoupler speed is critical for its performance. According to the Everlight 6N137 datasheet, maximum output rise and fall times are 40ns and 10ns, respectively. These represent the output voltage transition times when the input LED is pulsed with forward current. The inverse of the sum of these times closely approximates the maximum operating frequency under specified drive conditions.<\/p>\n\n\n\n<p>Fig. 1 shows how the 6N137 IC module looks and Fig. 2 shows its internal structure.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"500\" height=\"431\" src=\"https:\/\/www.electronicsforu.com\/wp-contents\/uploads\/2025\/04\/6N137-high-speed-optocoupler-isolation-module.jpg\" alt=\"PWM Signal Isolation Module Using 6N137 Optocoupler\" class=\"wp-image-162146\" style=\"width:362px;height:auto\" srcset=\"https:\/\/www.electronicsforu.com\/wp-contents\/uploads\/2025\/04\/6N137-high-speed-optocoupler-isolation-module.jpg 500w, https:\/\/www.electronicsforu.com\/wp-contents\/uploads\/2025\/04\/6N137-high-speed-optocoupler-isolation-module-487x420.jpg 487w, https:\/\/www.electronicsforu.com\/wp-contents\/uploads\/2025\/04\/6N137-high-speed-optocoupler-isolation-module-150x129.jpg 150w\" sizes=\"auto, (max-width: 500px) 100vw, 500px\" \/><figcaption class=\"wp-element-caption\">Fig. 1: 6N137 high-speed optocoupler isolation module<\/figcaption><\/figure><\/div>\n\n\n<p>PWM resolution defines the number of distinct duty cycles within a given period. A 10-bit resolution yields 1024 steps, while an 8-bit resolution provides 256. discrete duty cycles.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>Parts List<\/strong><\/td><\/tr><tr><td>Semiconductors:<br>IC1 &#8211; 6N137 high-speed<br>optocoupler<br>LED1 &#8211; 3mm LED (optional)<br>Resistors (all 1\/4-watt, \u00b15% carbon):<br>R1 &#8211; 330\u03a9<br>R2 &#8211; 4.7k\u03a9<br>R3 &#8211; 10k\u03a9<br>R4 &#8211; 1k\u03a9 (optional)<br>Capacitors:<br>C1 &#8211; 10nF ceramic disk<br>Miscellaneous:<br>CON1-CON3 &#8211; 2-pin connector<br>&#8211; 5V DC supply<br>&#8211; Wires and jumpers<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Circuit and Working<\/strong><\/h2>\n\n\n\n<p>Fig. 3 shows the circuit diagram of the PWM signal isolation module. The 100nF bypass capacitor (C1) is a crucial component. It can be either a ceramic or solid tantalum capacitor with good high-frequency characteristics; it should be connected as close as possible to the VCC and GND pins of the 6N137 (IC1). <\/p>\n\n\n\n<p>No pull-up resistor is required for the enable pin (VE), as the chip has an internal pull-up. Therefore, the external pull-up resistor (R3 shown in dotted line) is not necessary.<\/p>\n\n\n\n<div class=\"mepr_error\"><div class=\"locked-content\">\n<b>EFY++ CONTENT: ACCESS TO THIS CONTENT IS FREE! BUT YOU NEED TO BE A REGISTERED USER.<\/b><\/p>\n<p>Oops! This is an EFY++ article, which means it's our Premium Content. You need to be a Registered User of our website to read its complete content.<\/p>\n<p><b>Good News: <\/b>You can register to our website for FREE! <a href=\"https:\/\/www.electronicsforu.com\/plans\/subscription-plans\" target=\"_blank\" rel=\"noopener\">CLICK HERE<\/a> to register now.<\/p>\n<p><b>Already a registered member? <\/b>If YES, then simply login to you account below. (TIP: Use 'forgot password' feature and reset and save your new password in your browser, if you forgot the last one!)\n<\/div>\n<\/div><div>\n<div class=\"mp_wrapper mp_login_form\">\n                  <!-- mp-login-form-start -->     <form name=\"mepr_loginform\" id=\"mepr_loginform\" class=\"mepr-form\" action=\"https:\/\/www.electronicsforu.com\/login\" method=\"post\">\n            <div class=\"mp-form-row mepr_username\">\n        <div class=\"mp-form-label\">\n                              <label for=\"user_login\">Username<\/label>\n        <\/div>\n        <input type=\"text\" name=\"log\" id=\"user_login\" value=\"\" \/>\n      <\/div>\n      <div class=\"mp-form-row mepr_password\">\n        <div class=\"mp-form-label\">\n          <label for=\"user_pass\">Password<\/label>\n          <div class=\"mp-hide-pw\">\n            <input type=\"password\" name=\"pwd\" id=\"user_pass\" value=\"\" \/>\n            <button type=\"button\" class=\"button mp-hide-pw hide-if-no-js\" data-toggle=\"0\" aria-label=\"Show password\">\n              <span class=\"dashicons dashicons-visibility\" aria-hidden=\"true\"><\/span>\n            <\/button>\n          <\/div>\n        <\/div>\n      <\/div>\n            <div>\n        <label><input name=\"rememberme\" type=\"checkbox\" id=\"rememberme\" value=\"forever\" \/> Remember Me<\/label>\n      <\/div>\n      <div class=\"mp-spacer\">&nbsp;<\/div>\n      <div class=\"submit\">\n        <input type=\"submit\" name=\"wp-submit\" id=\"wp-submit\" class=\"button-primary mepr-share-button \" value=\"Log In\" \/>\n        <input type=\"hidden\" name=\"redirect_to\" value=\"\/wp-json\/wp\/v2\/posts\/162138\" \/>\n        <input type=\"hidden\" name=\"mepr_process_login_form\" value=\"true\" \/>\n        <input type=\"hidden\" name=\"mepr_is_login_page\" value=\"false\" \/>\n      <\/div>\n    <\/form>\n    <div class=\"mp-spacer\">&nbsp;<\/div>\n    <div class=\"mepr-login-actions\">\n      <a href=\"https:\/\/www.electronicsforu.com\/login?action=forgot_password\">Forgot Password<\/a>\n    <\/div>\n\n      \n    <!-- mp-login-form-end --> \n  <\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>This PWM (pulse width modulation) signal isolation module is built around the widely adopted 6N137 high-speed optocoupler. The device combines a high-efficiency input LED with an integrated optical photodiode detector IC to ensure robust signal isolation. The advanced 6N137 variants incorporate an open drain NMOS transistor output (photodetector logic gate), offering lower leakage than traditional [&hellip;]<\/p>\n","protected":false},"author":206064,"featured_media":162151,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22,23,6070,6072,3713],"tags":[1985,1911,110,12709],"class_list":{"0":"post-162138","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-electronics-projects","8":"category-hardware-diy","9":"category-advanced-projects","10":"category-beginners-projects","11":"category-premium","12":"tag-diy-projects","13":"tag-do-it-yourself","14":"tag-electronics-projects","15":"tag-may-2025"},"_links":{"self":[{"href":"https:\/\/www.electronicsforu.com\/wp-json\/wp\/v2\/posts\/162138","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.electronicsforu.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.electronicsforu.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.electronicsforu.com\/wp-json\/wp\/v2\/users\/206064"}],"replies":[{"embeddable":true,"href":"https:\/\/www.electronicsforu.com\/wp-json\/wp\/v2\/comments?post=162138"}],"version-history":[{"count":3,"href":"https:\/\/www.electronicsforu.com\/wp-json\/wp\/v2\/posts\/162138\/revisions"}],"predecessor-version":[{"id":162719,"href":"https:\/\/www.electronicsforu.com\/wp-json\/wp\/v2\/posts\/162138\/revisions\/162719"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.electronicsforu.com\/wp-json\/wp\/v2\/media\/162151"}],"wp:attachment":[{"href":"https:\/\/www.electronicsforu.com\/wp-json\/wp\/v2\/media?parent=162138"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.electronicsforu.com\/wp-json\/wp\/v2\/categories?post=162138"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.electronicsforu.com\/wp-json\/wp\/v2\/tags?post=162138"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}