kill sound with power off

[Doovieman]

Hi-
I'm using LM3875 for my amp. I have lots of caps on the power rails (something on the order of 7000uF total). I want to create a mute circuit such that when the power is cut, the sound is too. I don't want the caps to drain power to the chip for 10 seconds after I cut power. For a power supply, I have a regulated ladder supply with 2 voltages per rail. ie +32V and +15V, and -32V and -15V. The 15V rails are regulated with input coming from 32V output. Does anyone have any suggestions as to how to create a mute circuit for this situation? I was thinking about throwing a diode from output of regulator to input of regulator, but because there are two voltages (and two regulators), I wasn't sure if this would work. Any help is appreciated. Thanks,

Doovieman

[digi01]

I think you may do a simple relay module



this circuit can delay the sound when turn on and turn off the amp.

another,you can add a couple of 'drain resistors(10k-20k)' parallel with the power caps on the +/- rails.that may avoid the caps to power to the chip.


sorry my english

digi

[Doovieman]

Originally posted by digi01
I think you may do a simple relay module



this circuit can delay the sound when turn on and turn off the amp.

another,you can add a couple of 'drain resistors(10k-20k)' parallel with the power caps on the +/- rails.that may avoid the caps to power to the chip.


sorry my english

digi

Hi digi-
Thanks for the post. That looks like a good solution. Do you have any relays that you reccomend off the top of your head? Ideally pcb mount... Thanks for your time,

Doovieman

[Doovieman]

Anybody? What relay do you recommend?