Lm3886 / 2876 GC Project

I've designed a board to evaluate the Lm3886 and Lm2876's in stock and I need your opinion on how it looks.
 

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You're generally better off bringing the power supply in from the left side of the IC as this allows you to get the decoupling right up against the IC. Don't forget the 'middle cap' in the decoupling as well. You want a minimum of 470 uF at the power connector, 10 uF || 100 nF at the IC. That's covered in the LM3886 data sheet (see the application section). If you leave the 10 uF off, the LM3886 will oscillate at high output currents (so near the signal peaks).

In your PCB layout, you run the current from the V- decoupling network right through your signal ground. That current is pretty nasty, so if you want the data sheet performance out of the part, I suggest rerouting that. See: Grounding – Neurochrome

The recommendations in the LM3886 data sheet are from the mid 1990s. With more modern parts you can get even better decoupling. Have a look at my article on the subject: Taming the LM3886: Power Supply Decoupling – Neurochrome

Tom
 
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