AVR-Chat

I just read Amtel's AVR-based Constant Current Supply app note, which left me wondering why would you prefer an external chip for the current regulation.  What difficulty did you have with using just one chip?

--- In AVR-Chat@yahoogroups.com, "syberraith" <syberraith@...> wrote:
>
> Yep, I've been looking at the Maxim charger chips that setup up to work with a uControllers.  I have yet to run across any others.
> 
> I have a Duracell 15 minute NIMH charger, and was wondering why it killed batteries so fast.  After reading up on the charging methods for the different chemistries, now I know why.
> 
> --- In AVR-Chat@yahoogroups.com, David VanHorn <microbrix@> wrote:
> >
> > I did this a while back, in a Tiny-26 with the AVR also doing the PWM
> > constant current buck regulation.   However, if I was to do it again
> > today, I'd leave the current regulation to an external chip unless
> > forced to do it this way for cost.
> > 
> > I think that NIMH cells are probably the most complicated of the
> > common chemistries to work with, if you really follow all the rules.
> > They are just plain delicate.
> >
>