/diy/ - Do It Yourself

>>713972

Google "555 monostable". That'd be what you're looking for. Should also be able to find the formula for calculating the delay on the timer.

For a programmable microcontroller, you could use any of the GPIO pins to hook up to whatever indicator you're using.

>>713977

You're flat-out not going to be able to get a lower part count than by using a microcontroller (pic related; throw in a crystal and two capacitors if you want accurate timing), although, yes, you should be able to do cheaper.