LM3886 Pin 7 to Power or Signal Ground?

[GregH2]

Well I guess the title says it all.

Thanks,

Greg.

[tomchr]

Judging by the equivalent circuit in the data sheet (page 7), it looks like the ground connection is only used by the mute circuit. Thus, I'd return it to the power ground.

That said, the power ground and signal ground should meet at one point (star ground). You could also return the GND pin to this point via its own separate trace. That would eliminate any concern.

~Tom

[AndrewT]

I agree with Tom.
Pin 7 looks like it might pass modulated current under some operating conditions.

[kuldeepsingh]

By the way, In NS LM4780 reference PCB, the mute ground connects to signal ground and then to main ground via Rg. (page 22 of LM4780 NS datasheet)

[GregH2]

Great, thanks all.

Greg.