pcb power ground problem.

[qweets]

hello there.

I have a problem with my design.

I have an audio design placed together with an led system which is controlled by a micro controller (USB).
They both share the same Power supply which is causing problems I beleive.

The audio system sounds great by itself, that is until I connect up the micro controller USB and light up a few leds. Then there is a terrible interference noise and pulse sound.

I wonder do I need two separate ground planes and to somehow use diodes to separate the audio system power from the micro controller power?

Here is a schematic to help explain the system.

Your help is greatly appreciated. : )

 

[andre_luis]

You can reduce noising amount by spreading electrolytic+ceramic capacitors over supply bus.

( It is a little hard understand your diagram schematic, due doesn´t contain standard components symbols )





+++

 

[qweets]

hi, i just deleted a couple of unusual parts they were just pads that i was going to solder too.

I think the problem may be the audio ground is sharing the same as the USB ground?

 

[Audioguru]

The schematic has no contrast so it is difficult to see. Its parts are tiny because they are spread out too far apart.
I answered this thread a minute ago on another website forum (but there was no schematic).

 

[qweets]

I believe it is solved, the PSU was not powerful enough or failing . i changed the PSU and so far it is working. pheew : )