LM3886 power consumption in idle/mute mode

It is just this scheme from TI: AN-1192 Overture™ Series High Power Solutions with some modifications. Fig. 3.
CIN = 0,47 uF.
Ci1 = 10 uF elektrolyt
Rb = 47 kOhm.
The test is identical to the scheme. Nu snubber or serial to the speaker.
I will try to measure the output signal with 1N4148 diodes if it gives high frequency signal. My multimeter does not measure any AC signal…..
There is no distortion. It sounds realy very wel..
 

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There are no common resistors (of ca. 0,1 Ohm, what you mean probably).
It is just 2 x a single BTL. So 4 LM3886's (stereo BTL).

You do need those ballast resistors. Basically you're forcing the difference in DC offset between the two LM3886es in parallel across the ballast resistors. Higher resistance value -> lower wasted current but also lower max output power.

I'd insert 0.1-0.22 Ω in series with each output. I bet you'll find that'll reduce the standing current considerably.

Tom
 
It's only 6,5 mV / 8 Ohm < 1 mA through the speakers.
No speakers connected makes no difference.
I will let it go and accept the 97 mA rest current.
It works good. Cooling is enough, so not really a problem.
Much power for my piano and organ with only 2 x 19 V. That was my aim.

But it is a little bit strange that it is more than the 85mA max and 50 mA typ. of the TI specs .....