Basic Latch that makes sense

191

03:34:43

After seeing how weird my own attempts were I tried this design after someone mentioned it looked like I was trying to implement a basic latch. http://www.learningaboutelectronics.com/Articles/Latch-circuit-with-transistors.php

published 5 years ago

wyoelk

5 years ago

Y'all did well! Here's the circuit with just one power source. _ _ http://everycircuit.com/circuit/5254755734257664

poklmn

5 years ago

How it work?please

cannellajs2

5 years ago

@poklmn Note that you need both a NPN and a PNP for this. Initially the NPN's base is pulled to ground to which prevents flow from its base to emitter which keeps the base of the base of the PNP pulled high (stopping flow from its own emitter to base). When the on button is pressed the base of the NPN is active and this allowed current to flow arocc the NPN. This allows the base of the PNP to be pulled down, allowing current to flow across the PNP and through the LED. Also, note that this current is fed back to the base of the NPN pulling it up and keeping it open so when the on button is released it stays on. Pressing the off button grounds the base of the NPN thus shutting off the whole circuit and breaking the feedback.

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