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
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
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
An externally hosted image should be here but it was not working when we last tested it.
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
digi01 said:I think you may do a simple relay module
An externally hosted image should be here but it was not working when we last tested it.
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
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.