On Friday 05 August 2005 03:10 pm, Olin Lathrop scribbled:
> Sounds like a job for a 10F204.  You provide an analog level, and it runs a
> boost converter to maintain that voltage accross a low side current sense
> resistor.

I had considered a boost converter such as an MC34063, which with sufficiently 
high enough voltage, the current would be low enough not to require any 
external power transistor/fet.  But I really didn't want to add inductors or 
caps on this board for space reasons.  And since it was for someone else, I 
didn't want to give him anything with high voltages.

BTW, this circuit is also a quick project for someone else's custom truck so I 
don't want to write any code for it right now, but I think it might be an 
interesting exercise to write code for a DC-DC converter with a PIC.  Is this 
similar to regulating current for a stepper motor where the voltage across a 
sense resistor is controlled with PWM?

Cheers,
-Neil.


>
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