I have a simple circuit in my car. A +12V signal wire that comes from the ignition is used to tell an amplifier to power on.
When +12V is present here, the amp turns on and is powered by a separate, higher rated +12V feed from the battery.
The issue is that my car has start stop technology, so when I roll up to lights, the engine dies, and when I pull away, it starts again.
The +12V signal is present when the engine is not running, but when the car starts itself, it drops to 0V for a couple of seconds, before returning. I can only assume this is because the car routes the current through the starter relay instead.
My question is this. Is there a means of maintaining that 12V signal at an output for a couple of seconds after the input goes off? It literally only needs to be a couple of seconds, the input is back before long. I was thinking some kind of capacitor bank?
Let me know your thoughts.