Date   : Wed, 14 Oct 2009 23:47:25 +0100
From   : dm.hunt@... (David Hunt)
Subject: Power Supply Capacitors

> Does anyone know what the max current that can be drawn from the Master
> PSU
> on the 12 and 5v lines ?
> 
> The reason for asking is that I can choose between a long life capacitor
> that handles a 1000mA ripple and a shorter life but handles 2000mA ripple.
> It would seem to make sense that if 2A can be drawn from the 12v to go for
> the 2000mA ripple but if it isn't necessary then the longer life would be
> beneficial.

I thought the capacitor on the output side of the PSU was to shore up any
short term loads (transients) and wasn't there for ripple suppression?

The Master 128 can output at least 1A - that is what it says on the PSU. The
12V line is probably driven by a 7812 which has a 1A maximum rating.

Usually, when it comes down to capacitors, it's what space, you can get the
highest capacitance into, at the voltage you need. Ripple and ESR probably
aren't so important, being sat on the end of a voltage regulator.

Cheers

Dave ;)