[plug] re: ups

[Alan Howard]

On Wed, 08 Nov 2000, Kevin Shackleton wrote:
> So start a business making ATX power supplies that do just that . .
> 
> I'd buy one (version 1.1, not 1.0!)
> 
> K.
> 
> Alan Howard wrote:
> 
> > why is it that a power supply isn't made that allows both 240v and 12v
> > opperation
there is probably several ways of doing this. one is to have 2 seperate switch
mode power supplies, the normal one and one running on 12v , having the 12v one
only start when the mains died , isolating the outputs with diodes ( the newer
low forward voltage drop types ) . an other way would be to add a extra
winding on to the existing isolation/switching transformer and feed it with
push pull type drive , with associated circuitry for regulation, or you could
use a 240v to 12v supply that then feeds an other power supply that then
generates the required rails for the computer. any other ideas?

regards
alan howard