Latching Circuit

Thread Starter

wolfhunter9154

Joined Mar 31, 2013
2
Hello everybody, I've been working on a project for a few days and I'm having a little trouble with it. What I want to do is have the alarm from watch trigger a light that stays on until power is removed from the circuit. I have tried this with NOR gates with the outputs "crossed". However, for some reason, it will not hold the state it should be in and it will flicker on and off. This needs to be done with solid state devices, and I currently only have npn transistors, so the PNP and NPN latch isnt really an option right now. Any help is greatly appreciated.
 

Thread Starter

wolfhunter9154

Joined Mar 31, 2013
2
Thanks, I ended up using a buffer with the output looped to the input. It didn't work the first time before I posted, but I tried again with a resistor from the input to ground and it stopped the flickering.
 
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