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Subject: [motm] Re: [Q] Power Rail Conditioning

From: media.nai@...
Date: 2003-04-10

>If your circuit draws a lot of power you might consider a larger value such
>as 33uF or 50uF.

Yet don't make it too big. Consider two caps -- one big, one small.

>In addition it is a good practice to liberally sprinkle
>bypass caps throughout the circuit board. The MOTM choice is
>a .01uF axial cap.

They are also ceramic, a radial lead ceramic might work even better.

>There should generally be at least 1 bypass cap
>for each power supply voltage every other IC chip, located as close
>as possible to the chip.

Yes, it is very important to place it as close as possible.

>If your circuit includes additional voltage regulators you would
>want to have an electrolytic cap and ferrite on the output of each
>regulator as well.

I agree about the cap, but I don't see the point in adding an
inductor. Ferrite beads are useful keeping noise from coming down
the pike into each PCB, but what is the advantage when used with a
local regulator, such as a low-current three-legged regulator
providing 5V to a few logic chips??