I have a rear-view camera circuit in my car that I'm triggering from the reverse lamp 12v feed. All good so far, works a treat...except my cars lighting system periodically sends short 12v pulses to the reverse lamps to check the bulbs haven't blown. Those pulse make my reverse camera flash on briefly.
How can I stop that from happening? I thought a simple capacitor might do the trick, but couldn't get that to work. A delay-on timer circuit would do it I guess, but I'd like to have an infinitely long on time, as long as the 12v trigger is still present. I've not seen that on any 555 timer circuits - any ideas?
Thanks everyone, any ideas much appreciated!
Edit: will post specifics of pulses later, have got them stored in my scope. Appreciate all solutions, but the simpler & cheaper the better! Thanks again!
Edit: pulses are only just over 8 V DC, might be able to filter them out on that basis? They're about 1.2 ms each. See attached image.