Hi,
I built this circuit for a battery charger,
http://www.members.dca.net/kben/charger.html
with a few modifications.
I am using a F872, and a TIP41C for the
transistor. I also have the 1k resistor tied to
+5v not the MCLR pin as in the circuit. I am
driving the base of the transistor with the
PWM pin from the F872.
I am using a 20VAC 800ma wall wart, and
2Khz for the PWM. When the CCPR1L is set to
zero, I see 1.3A charging my 8XAA Nimh battery
pack. If I change CCPR1L to 3 I see 933ma,
CCPR1L to 6 I see 900ma,CCPR1L to 12 I see 750ma,
charging, so far so good. If I set CCPR1L
higher than 15 the charging current drops to zero.
Any ideas why ? I thought I would be able to lower
the current down to 150ma for a trickle charge.

Thanks in advance,
Kevin

P.S. I am a programmer, not an EE, so maybe it's
something dumb, but you got me ?

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