On Fri, Jul 13, 2007 at 04:07:22PM +0000, Poul-Henning Kamp wrote: > In message <[EMAIL PROTECTED]>, 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. -- B.Walter http://www.bwct.de http://www.fizon.de [EMAIL PROTECTED] [EMAIL PROTECTED] [EMAIL PROTECTED] _______________________________________________ Soekris-tech mailing list [email protected] http://lists.soekris.com/mailman/listinfo/soekris-tech
