Bypass cap's

[Edu Silva]

Steve Varner wrote:

> Where do you put these in the circuit and what size caps do you use?
> (5-10 microfarad?)

I do like this...

>From
power  (+)
supply >----100R----+---> to the
board               |     circuit (+)
                    |+
                  100uF
                    |-
                    |
                  ground

..... at the supply inputs of the PCB, and this...

>-----+------> IC supply
(+)   |        pin (+)
      |
    0.1uF
      |
      |
    ground

..... near each IC. Invert the polarity for the negative rail.

>Is noise to and from the board via suply lines really that much of a
>problem?

Sometimes. To be safe, (isn't an overkill...) place regulator IC's (7815
and 7915) at the supply rails of each circuit board. The main supply should
be at least 18 volts, to make things work.

You can find datasheets at:
http://www.national.com/catalog/AnalogRegulators.html

Have fun!
Edu

_____________________
Edu Silva - ES2 Audio
Salvador-Bahia-Brazil