Hi all - LM3886 has a mute function but not standby like the TDA729x...Does anyone have a method for putting the amp chips into a low or no power mode when not in use such as in a 5channel config for HT but you are using only 2 channels...I see no reason to keep 3 or 4 watts dissipating from the other 3 chips...My only ideas are one of the following:
1. Install a DPDT switch that connects V+ and V- from the IC...crudest method I can think of but does constant power on and off cause any harm?
2. Circuit that detects an input signal and powers on the amp if signal is detected similar to subwoofer amps
1. Install a DPDT switch that connects V+ and V- from the IC...crudest method I can think of but does constant power on and off cause any harm?
2. Circuit that detects an input signal and powers on the amp if signal is detected similar to subwoofer amps
Don't overthink it 
I bet it pulls 100mA or so idle, no big deal.
No harm will be done by "constant" ON/OFF switching but why would you do that on a continuous base?
IF it's so important for you, you can add a relay switching +/-V rails, and a circuit triggering it on/off depending on availability of signal in those channels.
I bet it pulls 100mA or so idle, no big deal.
No harm will be done by "constant" ON/OFF switching but why would you do that on a continuous base?
IF it's so important for you, you can add a relay switching +/-V rails, and a circuit triggering it on/off depending on availability of signal in those channels.
50 mA, typical. 85 mA worst case according to the data sheet.
Why burn the power if you don't need it?
Um. No. It has a mute pin. It's not a slow start pin. It just switches the bias current from the main input pair to the mute pair.
Nope. It doesn't. See the equivalent circuit on Page 7 of the LM3886 data sheet. I describe the functionality in a bit more detail on my taming the LM3886 pages.
Tom
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