Re: LM78XX imput/output capacitors



"vincent.thiernesse" wrote:

Hello,

these are minimum values.

the input capacitor doesn't replace the filter capacitor.

for the filter capacitor, take 1000uF per Ampere for 1 volt input variation.

I take it you mean ripple ? Your numbers are out by about 7-8:1

You need ~ 8000uF for 1V (pk-pk) of ripple @ 1A load and 50Hz.

Graham

.

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