12Vdc slowed power off circuit
12Vdc slowed power off circuit
(OP)
Hi Guys,
So I installed a new head unit in my car the other day and now I get a pop out of the speakers when the head unit is powered off. I figure I can solve this by building a circuit that will let the voltage decay to zero of a second or two. There's is also a very slight pop when powering on so the circuit should work on power up as well. I apologize in advance for not being quite the wiz I'd like to be with circuit design. Thanks Guys!
So I installed a new head unit in my car the other day and now I get a pop out of the speakers when the head unit is powered off. I figure I can solve this by building a circuit that will let the voltage decay to zero of a second or two. There's is also a very slight pop when powering on so the circuit should work on power up as well. I apologize in advance for not being quite the wiz I'd like to be with circuit design. Thanks Guys!





RE: 12Vdc slowed power off circuit
Decaying the power supply voltage might help, or it might just delay the pops. You could experiment with a variable power supply, if you can put your hands on one with adequate current capability.
An old trick is a series resistor to 'slow' the current input, and use the rising voltage after the relay to close relay contacts across the resistor once the voltage has risen to the relay's pull-in voltage. This wouldn't help with power off.
Car stereo shops often have a selection of 'farad' class capacitors. They'd provide a fraction of a second 'decay' after the power supply was cut. They'd also potentially cause a large current spike on application of power.
These contradictory requirements are why the mute option is better.
RE: 12Vdc slowed power off circuit
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers
RE: 12Vdc slowed power off circuit
IRstuff, how would that work in the system, would that be able to act as a sound muting circuit like mentioned above?
Thanks for the response guys!
RE: 12Vdc slowed power off circuit
TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers