[sdiy] +-12V supply

[harrybissell]

That is exactly the point...and I might add that it is also a PowerOne 800mA
supply that needed this treatment. :^P  I just added a series power resistor (15
ohms)
in my case... with a one shot that delays a relay closure for two seconds. When
closed
the relay shorts out the resistor.

H^) harry

groovyshaman wrote:

> I am curious Harry - what is the advantage of a soft start mechanism?  Does
> this in some way help alleviate the initial heavy current outrush that
> occurs when turning on the power due to all of the decoupling caps on all of
> the modules in my system?
>
> I've noticed that from time to time when I power up the 800ma power one, one
> rail "goes flat" due to current limit circuitry I think - and I immediately
> shutdown when this occurs.  Hopefully this does not harm things.  (although
> I think I remember someone mentioning that running certain ICs with one dead
> rail for any length of time will kill the part..)  I'm still running the
> supply below the rated output once things power up ok.  It's the initial
> current draw that's causing problems.
>
> George
>
> ----- Original Message -----
> From: "harrybissell" <harrybissell at prodigy.net>
> To: "Ken Stone" <sasami at hotkey.net.au>
> Cc: <synth-diy at dropmix.xs4all.nl>
> Sent: Friday, January 14, 2005 11:41 PM
> Subject: Re: [sdiy] +-12V supply
>
> > I considered building a relay based "soft start" for my PowerOne
> > supply as "building my own power supply".  The only time I would
> > build my own is....
> >
> > 1) when I want cheap and dirty and don't care about performance
> >
> > 2) when it has to fit into a custom sized area
> >
> > 3) when I need an odd voltage not readily available
> >
> > H^) harry
> >
> <snip>