[Soekris] Powersupply Net4801

[Bernd Walter]

On Fri, Jul 13, 2007 at 04:07:22PM +0000, Poul-Henning Kamp wrote:
> In message <001d01c7c565$725e4d20$0d0aa8c0 at egbert>, Egbert Jan writes:
> 
> >Now I had another sneaky plan: to feed the
> >diskdrive via a separate regulator (7805).
> 
> A 7805 will not be able to start a disk, most disks have peak
> current demands well over 1A during spinup.

Can't say if this is realy true for 2,5" drives, but it might be
possible and it is shurely the case for most 3,5" drives.
However - I wouldn't use an 7805 for that purpose anyway, since with
12V supply you would loose almost 60% of the power at the regulator.
My suggestion is an LM2576-5 or LM2596-5, which are small switching
regulators, which requires only a few external components.
The later is a bit more expensive, but has a higher switching rate and
runs with a smaller coil.

Or, as someone else already suggested, use a 5V supply.
Which is what I did to get a two headed Matrox G450 running in an 4801.

I also used a open frame 12V/5V supply inside a custom case to run
a 3,5" drive attached to an 4801.

-- 
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