{"id":4853,"date":"2021-06-15T07:32:18","date_gmt":"2021-06-15T05:32:18","guid":{"rendered":"https:\/\/dcaclab.com\/blog\/?p=4853"},"modified":"2022-11-21T19:24:29","modified_gmt":"2022-11-21T17:24:29","slug":"how-to-build-a-blinking-led-using-resistors-capacitors-and-transistor-in-dcaclab","status":"publish","type":"post","link":"https:\/\/dcaclab.com\/blog\/how-to-build-a-blinking-led-using-resistors-capacitors-and-transistor-in-dcaclab\/","title":{"rendered":"How to build a blinking LEDs using Resistors, Capacitors, And Transistor in DCAClab"},"content":{"rendered":"<p>It is possible to blink or flash an LED using just a transistor? <b>Transistor flashing led circuit <\/b>makes use of a rarely used property of the transistor known as the reverse avalanche breakdown. Since this is a non-standard feature, this may not work on all NPN transistors. Also, note that you may need more than 9V voltage for this to get working on most transistors. I was able to get this working on the EBC transistor with a 9V supply.<\/p>\n<p>In reverse avalanche mode, the collector to emitter circuit of the transistor is connected in reverse polarity. Hence positive terminal of the power source is connected to the emitter and the collector is connected to the negative terminal. In usual operation, very little current will flow from emitter to collector in this configuration. However, if we increase the voltage of the power source, beyond a specific value, the emitter to collector junction breaks down and a large current will flow through the circuit. The base of the transistor is not used at all in this configuration.<\/p>\n<h2><span style=\"color: #008000;\">How Blinking LED with Transistor Works?<\/span><\/h2>\n<p>When the circuit is connected to the 9V battery, the current starts flowing through the 470 Ohms resistor charging the 470uF capacitor. This steadily increases the emitter to collector voltage in the transistor. When the voltage reaches the reverse avalanche breakdown region of the transistor, the emitter to collector junction breaks down and the capacitor is discharged through the 100ohm resistor and the LED. This lights up the LED. In the avalanche breakdown region, the transistor exhibits negative resistance, higher current leads to lower resistance!<\/p>\n<p>Due to the discharge, capacitor charge and voltage drops until the avalanche mode cannot be any longer sustained. The transistor enters its normal operation and the emitter to collector high resistance is automatically restored. This switches off the LED triggering another cycle of capacitor charge and discharge!<\/p>\n<p><strong><span style=\"color: #339966;\">Note: That we are using the base of the transistor in this circuit.<\/span><\/strong><\/p>\n<p style=\"text-align: justify;\"><span style=\"color: #000000;\">A very simple circuit that you can build to blink or flash LEDs. The circuit is built using transistors, resistors, capacitors, and LEDs. Of course, you will need a breadboard, wire jumpers, and a power source. The parts list includes:<\/span><\/p>\n<ol>\n<li><span style=\"color: #0000ff;\">NPN Transistor, 100hFE,\u00a0 Qty: 3<\/span><\/li>\n<li><span style=\"color: #0000ff;\">Resistor, value 470 Ohms, qty: 6<\/span><\/li>\n<li><span style=\"color: #0000ff;\">One terminal Vs, 9V Qty: 3<\/span><\/li>\n<li><span style=\"color: #0000ff;\">Capacitor, 470 uF, Qty: 3<\/span><\/li>\n<li><span style=\"color: #0000ff;\">LED, Qty: 3<\/span><\/li>\n<li><span style=\"color: #0000ff;\">Breadboard<\/span><\/li>\n<li><span style=\"color: #0000ff;\">Jumper wires<\/span><\/li>\n<\/ol>\n<h2><strong><span style=\"color: #008000;\">Add 3 Transistors in DCAClab&#8217;s Breadboard:<\/span><\/strong><\/h2>\n<p><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"4854\" data-permalink=\"https:\/\/dcaclab.com\/blog\/how-to-build-a-blinking-led-using-resistors-capacitors-and-transistor-in-dcaclab\/dc1\/\" data-orig-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/DC1.png?fit=1274%2C625&amp;ssl=1\" data-orig-size=\"1274,625\" data-comments-opened=\"0\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"DC1\" data-image-description=\"\" data-image-caption=\"\" data-medium-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/DC1.png?fit=300%2C147&amp;ssl=1\" data-large-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/DC1.png?fit=1024%2C502&amp;ssl=1\" class=\"alignnone size-full wp-image-4854\" src=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/DC1.png?resize=1274%2C625&#038;ssl=1\" alt=\"\" width=\"1274\" height=\"625\" data-recalc-dims=\"1\" \/><\/p>\n<p>Add the three NPN transistors and the jumper wires from the power BUS to the emitter of each transistor. Because of the way I inserted the Three transistors the emitter is on the left side of 3 transistors.<\/p>\n<h2 class=\"step-title\"><span style=\"color: #008000;\">Add the Capacitors:<\/span><\/h2>\n<p><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"4855\" data-permalink=\"https:\/\/dcaclab.com\/blog\/how-to-build-a-blinking-led-using-resistors-capacitors-and-transistor-in-dcaclab\/dc2\/\" data-orig-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/DC2.png?fit=1274%2C625&amp;ssl=1\" data-orig-size=\"1274,625\" data-comments-opened=\"0\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"DC2\" data-image-description=\"\" data-image-caption=\"\" data-medium-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/DC2.png?fit=300%2C147&amp;ssl=1\" data-large-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/DC2.png?fit=1024%2C502&amp;ssl=1\" class=\"alignnone size-full wp-image-4855\" src=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/DC2.png?resize=1274%2C625&#038;ssl=1\" alt=\"\" width=\"1274\" height=\"625\" data-recalc-dims=\"1\" \/><\/p>\n<p>Connect the Three capacitors to the circuit. Connect the positive lead of the first capacitor to the collector of transistor 1 Next connect the negative lead of the same capacitor to the emitter of transistor 1.<\/p>\n<p>Repeat the above process for the second capacitor. Connect the positive lead of the second capacitor to the collector of transistor 2. Connect the negative lead of the same capacitor to the emitter of transistor 2 and repeat the above process for the Third capacitor.<\/p>\n<h2 class=\"step-title\"><span style=\"color: #008000;\">Add the 470 Ohms Resistors &amp; ground:<\/span><\/h2>\n<p><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"4857\" data-permalink=\"https:\/\/dcaclab.com\/blog\/how-to-build-a-blinking-led-using-resistors-capacitors-and-transistor-in-dcaclab\/dc3-2\/\" data-orig-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/dc3-1.png?fit=1274%2C625&amp;ssl=1\" data-orig-size=\"1274,625\" data-comments-opened=\"0\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"dc3\" data-image-description=\"\" data-image-caption=\"\" data-medium-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/dc3-1.png?fit=300%2C147&amp;ssl=1\" data-large-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/dc3-1.png?fit=1024%2C502&amp;ssl=1\" class=\"alignnone size-full wp-image-4857\" src=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/dc3-1.png?resize=1274%2C625&#038;ssl=1\" alt=\"\" width=\"1274\" height=\"625\" data-recalc-dims=\"1\" \/>Next, connect the 470 Ohms Three resistors to the transistors. One lead of the resistor connects to the collector of the transistor, the emitter lead connects to the ground. Do this for both transistors.<\/p>\n<h2 class=\"step-title\"><span style=\"color: #008000;\">Add the LEDs &amp; Source:<\/span><\/h2>\n<p><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"4858\" data-permalink=\"https:\/\/dcaclab.com\/blog\/how-to-build-a-blinking-led-using-resistors-capacitors-and-transistor-in-dcaclab\/dc4\/\" data-orig-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/dc4.png?fit=1274%2C625&amp;ssl=1\" data-orig-size=\"1274,625\" data-comments-opened=\"0\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"dc4\" data-image-description=\"\" data-image-caption=\"\" data-medium-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/dc4.png?fit=300%2C147&amp;ssl=1\" data-large-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/dc4.png?fit=1024%2C502&amp;ssl=1\" class=\"alignnone size-full wp-image-4858\" src=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/dc4.png?resize=1274%2C625&#038;ssl=1\" alt=\"\" width=\"1274\" height=\"625\" data-recalc-dims=\"1\" \/><\/p>\n<p>Add all 470 Ohm resistors along with the LEDs. I added a picture of a transistor to identify the Emitter, Base, and Collector. Connect one wire of the first resistor to the collector of transistor 1. The other resistor wire then connects to the positive wire of the first LED. Follow the same steps for the other resistor and LED. Connect one wire of the second resistor to the base of transistor 2 and repeat all resistors.<\/p>\n<h2 class=\"step-title\"><span style=\"color: #008000;\">Supply Power and Watch the LEDs Blink:<\/span><\/h2>\n<p><img loading=\"lazy\" decoding=\"async\" data-attachment-id=\"4859\" data-permalink=\"https:\/\/dcaclab.com\/blog\/how-to-build-a-blinking-led-using-resistors-capacitors-and-transistor-in-dcaclab\/dc5\/\" data-orig-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/dc5.png?fit=1014%2C625&amp;ssl=1\" data-orig-size=\"1014,625\" data-comments-opened=\"0\" data-image-meta=\"{&quot;aperture&quot;:&quot;0&quot;,&quot;credit&quot;:&quot;&quot;,&quot;camera&quot;:&quot;&quot;,&quot;caption&quot;:&quot;&quot;,&quot;created_timestamp&quot;:&quot;0&quot;,&quot;copyright&quot;:&quot;&quot;,&quot;focal_length&quot;:&quot;0&quot;,&quot;iso&quot;:&quot;0&quot;,&quot;shutter_speed&quot;:&quot;0&quot;,&quot;title&quot;:&quot;&quot;,&quot;orientation&quot;:&quot;0&quot;}\" data-image-title=\"dc5\" data-image-description=\"\" data-image-caption=\"\" data-medium-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/dc5.png?fit=300%2C185&amp;ssl=1\" data-large-file=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/dc5.png?fit=1014%2C625&amp;ssl=1\" class=\"alignnone size-full wp-image-4859\" src=\"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/dc5.png?resize=1014%2C625&#038;ssl=1\" alt=\"\" width=\"1014\" height=\"625\" data-recalc-dims=\"1\" \/><\/p>\n<p>Finally, the last step is to supply power and watch the LEDs blink. I use a 9-volt battery and it worked fine.<\/p>\n<p>For fun, you can try other capacitor values to change the rate at which the LEDs blink.<\/p>\n<h5>To see live simulation: Click the link: <a href=\"https:\/\/dcaclab.com\/en\/experiments\/37040-build-a-blinking-leds-with-transistor-and-capacitor\" target=\"_blank\" rel=\"noopener noreferrer\">Build A Blinking LEDs with-Transistor-and-Capacitor<\/a><\/h5>\n<hr \/>\n<p><a href=\"https:\/\/dcaclab.com\/users\/28506\/profile\">Instructor<\/a><\/p>\n<p><a href=\"https:\/\/dcaclab.com\/blog\/author\/anisur\/\">Md. Anisur Rahman Likhon<\/a><\/p>\n<hr \/>\n","protected":false},"excerpt":{"rendered":"<p>It is possible to blink or flash an LED using just a transistor? Transistor flashing led circuit makes use of a rarely used property of the transistor known as the reverse avalanche breakdown. Since this is a non-standard feature, this may not work on all NPN transistors. Also, note that you may need more than [&hellip;]<\/p>\n","protected":false},"author":6,"featured_media":4859,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"footnotes":"","jetpack_publicize_message":"","jetpack_is_tweetstorm":false,"jetpack_publicize_feature_enabled":true},"categories":[20,21,22],"tags":[],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2021\/06\/dc5.png?fit=1014%2C625&ssl=1","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p9HmdS-1gh","jetpack_likes_enabled":true,"jetpack-related-posts":[{"id":4698,"url":"https:\/\/dcaclab.com\/blog\/pnp-transistor-working-and-application-explained\/","url_meta":{"origin":4853,"position":0},"title":"PNP Transistor Working and Application Explained","date":"September 13, 2020","format":false,"excerpt":"A PNP transistor is nothing but a bipolar junction transistor (BJT). It is made by sandwiching an n-type semiconductor between the two p-type semiconductors. This transistor is a three-terminal device. The terminals are namely, emitter (E), base (B), and collector (C). The PNP transistor acts as two PN junction diodes\u2026","rel":"","context":"In &quot;General Electronics&quot;","img":{"alt_text":"PNP Transistor Working","src":"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2020\/09\/PNP-Transistor-Working.png?fit=469%2C264&ssl=1&resize=350%2C200","width":350,"height":200},"classes":[]},{"id":4724,"url":"https:\/\/dcaclab.com\/blog\/npn-transistor-working-and-application-explained\/","url_meta":{"origin":4853,"position":1},"title":"NPN Transistor Working and Application Explained","date":"October 25, 2020","format":false,"excerpt":"NPN transistor is a three-terminal device having a p-type semiconductor sandwiched between the two n-type semiconductors. It is the most useful of the two bipolar junction devices. The other being the PNP transistor. It has various applications and is used mostly for amplification and switching. Well, before moving into the\u2026","rel":"","context":"In &quot;General Electronics&quot;","img":{"alt_text":"","src":"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2020\/10\/Transistors.png?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":4184,"url":"https:\/\/dcaclab.com\/blog\/how-to-use-transistors\/","url_meta":{"origin":4853,"position":2},"title":"How to use Transistors in DCACLAB (both NPN and PNP)","date":"October 23, 2018","format":false,"excerpt":"In this Post you will know that how to use Transistor in DCACLab (both NPN and PNP). BJT (Bipolar Junction Transistor) also Generally known as a transformer is an active electronic component used in either signal amplification or logic switches in signal processing. The transistor is a semiconductor device just\u2026","rel":"","context":"In &quot;Features&quot;","img":{"alt_text":"using pnp transistor in DCACLab","src":"https:\/\/i0.wp.com\/dcaclab.com\/blog\/wp-content\/uploads\/2018\/10\/using-pnp-transistor-in-DCACLab.jpg?fit=574%2C358&ssl=1&resize=350%2C200","width":350,"height":200},"classes":[]},{"id":4940,"url":"https:\/\/dcaclab.com\/blog\/how-to-build-dark-activated-led-light\/","url_meta":{"origin":4853,"position":3},"title":"How to build Dark Activated LED Light","date":"November 12, 2022","format":false,"excerpt":"This is a circuit whose light will turn on once it is exposed to darkness. So it's a light that will come on when it gets dark such as at night time. This is extremely useful for people who may live in a house that has vision problems and need\u2026","rel":"","context":"In &quot;Features&quot;","img":{"alt_text":"","src":"https:\/\/i0.wp.com\/s3.amazonaws.com\/dcaclab.wordpress\/wp-content\/uploads\/2022\/11\/12101822\/Capture-9.png?fit=626%2C372&ssl=1&resize=350%2C200","width":350,"height":200},"classes":[]},{"id":4964,"url":"https:\/\/dcaclab.com\/blog\/how-to-build-simple-12-volt-car-battery-charger-circuit\/","url_meta":{"origin":4853,"position":4},"title":"How to build Simple 12 Volt Car Battery Charger Circuit","date":"December 19, 2022","format":false,"excerpt":"We will create a \" 12 Volt Battery Charger Circuit\" in this guide. To charge batteries, we implement a voltage to the terminals and the battery begins to charge. The charging protocol is determined by the size and type of battery that is being charged. Some types of batteries have\u2026","rel":"","context":"In &quot;Features&quot;","img":{"alt_text":"","src":"https:\/\/i0.wp.com\/s3.amazonaws.com\/dcaclab.wordpress\/wp-content\/uploads\/2022\/12\/19073655\/Capture.png?fit=706%2C366&ssl=1&resize=350%2C200","width":350,"height":200},"classes":[]},{"id":4741,"url":"https:\/\/dcaclab.com\/blog\/switch-mode-power-supply-explained-in-detail\/","url_meta":{"origin":4853,"position":5},"title":"Switch Mode Power Supply Explained in Detail","date":"November 15, 2020","format":false,"excerpt":"A switch mode power supply, generally known as SMPS is an electronic device that is used to convert electrical power efficiently. This SMPS is more complex than conventional linear power supplies. The complexity increases but it give many advantages over the linear power supply. Why do we need a Linear\u2026","rel":"","context":"In &quot;General Electronics&quot;","img":{"alt_text":"","src":"https:\/\/i0.wp.com\/s3.amazonaws.com\/dcaclab.wordpress\/wp-content\/uploads\/2020\/11\/15182732\/SMPS.png?fit=571%2C239&ssl=1&resize=350%2C200","width":350,"height":200},"classes":[]}],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/dcaclab.com\/blog\/wp-json\/wp\/v2\/posts\/4853"}],"collection":[{"href":"https:\/\/dcaclab.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dcaclab.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dcaclab.com\/blog\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/dcaclab.com\/blog\/wp-json\/wp\/v2\/comments?post=4853"}],"version-history":[{"count":9,"href":"https:\/\/dcaclab.com\/blog\/wp-json\/wp\/v2\/posts\/4853\/revisions"}],"predecessor-version":[{"id":4952,"href":"https:\/\/dcaclab.com\/blog\/wp-json\/wp\/v2\/posts\/4853\/revisions\/4952"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/dcaclab.com\/blog\/wp-json\/wp\/v2\/media\/4859"}],"wp:attachment":[{"href":"https:\/\/dcaclab.com\/blog\/wp-json\/wp\/v2\/media?parent=4853"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dcaclab.com\/blog\/wp-json\/wp\/v2\/categories?post=4853"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dcaclab.com\/blog\/wp-json\/wp\/v2\/tags?post=4853"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}