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Dave Plowman (News)

In article ,
Bob Larter wrote:
wrote:
On Sep 11, 10:13 am, "Dave Plowman (News)"
wrote:
In article ,
D Yuniskis wrote:

I've got a (Vellerman) PWM device which is DC controlled. I'd like
to use it such that it fades up to max when a simple DC switch is
made, then fades out when it is broken. I can get it to do this
using a simple RC circuit - but the 'law' of the fades isn't as
linear as I'd like. Any clever way of doing it?
Constant current source into a cap.
The constant current source into the cap is easy enough - but the
constant current load?

OK you don't like that. How about an up/down counter and a DAC?

Well, that's about as linear as you're going to get. ;^)

Sadly rather uncharted territory with me - I'm more an OC71 sort of
guy. ;-)

--
*When you've seen one shopping centre you've seen a mall*

Dave Plowman London SW
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