Hi Tom,
I included part of my original post below.
The circuit was designed for 100KHz.
I am using 500Hz.
I have my DMM inserted in the circuit to
measure the current. The circuit seems to be
functioning OK as the battery pack charges at
the right level, I am using a F872, and monitor
the temp of the pack also, to make sure it does not
get to hot. The problem was the wall wart heating up.

>        a) What frequency is your circuit working at?
>        b) How are you determining that the battery is charging at the correct

>current?
.
http://www.members.dca.net/kben/misc/buck.html
I am also using a 500Hz PWM, not 100Khz.
I am able to
control the charging current OK with the PWM from my PIC.
The charger has 3 modes full 1000ma, soft 375ma,
and trickle 75ma.

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