single sided lm3875 diy pcb

[jayveesea]

hello,

I'm wondering if there is any proven single sided lm3875 layouts available (that I can make myself). I've found a couple in these forums...

this particular thread has two: layout1 and layout2, and another thread has this layout3.

...but its unclear how successful these are.

so I guess I'm curious if anyone has built these or some other layout. right now I'm leaning towards the first link because it looks the easiest to make.

thanks,
jvc

 

[bender460]

http://www.diyaudio.com/forums/chip-amps/162099-lm3886-schematics-pcb.html

I have successfully built a couple of these.

 

[tomchr]

http://www.diyaudio.com/forums/chip-amps/162099-lm3886-schematics-pcb.html

I have successfully built a couple of these.

It needs at least 470 uF per rail of decoupling cap, though. That's National Semiconductor's recommendation, by the way.

Of the three layouts in Post #1, Layout #2 is the least bad. The supply routing is decent, though it could easily be improved by using pours rather than traces. Layouts #1 and #3 will have high supply rail induced distortion due to the rails being on opposite ends of the PCB. Layout #1 is the only one that implements the grounding well with the signal ground and power ground coming together at the output ground.

You can read some of my thoughts on chipamp design and layout here: http://www.neurochrome.com/taming-the-lm3886-chip-amplifier/

Tom

 

[jayveesea]

thanks bender! i think i might go with that project.

i'm surprised that there is not a similar thread for a lm3875 circuit, but this is close enough.

 

[jayveesea]

thanks tomchr! still going through all that content, i'll try to apply those thoughts on the lm3886 apex design.