Rather than a battery backup, why not just build a flyback or SEPIC dc-dc=
=20
converter that will work from 8 to say 14V?

Cheers,
-Neil.



On Friday 18 July 2003 04:29, Peter Moreton scribbled:
> A bit off-topic, but I'll ask anyhow: I have been asked to come up with
> a vehicle 'mini-UPS' design, something that takes 12v (car DC) in and
> produces 12v @3amp and 5V @6amp out. The PSU must be able to maintain
> power for a few seconds when the vehicle is started, and the battery ma=
y
> dip to say, 8v.
>
> I guess I'll end up with some switcher design & and small NIMH / NICAD
> battery pack able to provide a few amps to the PSU input for a minute o=
r
> so, but wonder if the listers have any thoughts on this problem? Any
> great IC / regulator chips out there that solve this problem?
>
> Thanks, Peter Moreton

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