Question about 7805/7905 1

[2sb18]

Hi,

I'm building a system that has analog and digital circuitry. I had two questions:

1) The system includes high end audio. Is using a 7805/7905 combination for the power supply a bad idea? Are they good enough?

2) Should I seperate the digital power from the analog power? As in, should I have two seperate 7805s?

Thanks,
Steve.

 

[ScottyUK]

Steve,

1) Use +/-15V for the analogue supply rails. You will have much more signal headroom and should also get a better SNR.

2) Yes.

Consider buying a book like 'The Art of Electronics' by Horowitz & Hill. Although it's getting old these days, the principles of analogue and digital design are still sound. It is a very readable book without a lot of heavy maths. You may find some of the ICs referred to have been superceded, but finding modern equivalents should be quite easy.



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