On Fri, 5 Dec 2003, Denny Esterline wrote:

> > > > So - anyone have any ideas on how to scale a 0-90V source to 0-3.42V
> at
> > > about a third of an amp current, efficiently and compactly, and without
> > > requiring a seperate power supply?
> >
> >
> > Why this voltage range?
> >
> > What are you trying to measure - voltage or current?
> >
> >
> Read the earlier posts in this thread, he's trying to power an led module
> from the 90 volt source.
>

  I hope, God help me, you (the initial asker) are not student at MIT...
:)
Because, in the wild Africa, any bushman knows that a LED is supplied in
current and not in voltage. So it does not means you have a 10V supply or
a 90V supply if you know how to compute the power of the ballast device
(resitance, curent constant regulator, etc)

If you need just a divider from 0-90V to 0-3.42V, then use the "divider
theorem" or the Ohm law, choosing a convenient current through divider.

I'm not harsh, grumpy or nasty. Just amused, so don't be angry.

best, Vasile

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