I would like to use a couple of spare PIC pins to pulse charge a 3.6v NiCad
battery (aka ). I assume this can be done by using three PIC pins:

* Pin A: detect if external power is applied (ie stop draining the battery
and start charging it, if necessary)
* Pin B: send the PWM pulses to the NiCad to charge it
* Pin C: read the battery voltage to see if it is charged

Pin A & C are obviously straight forward. Pin B is the bit that's new to
me. I am not sure how simple/elaborate to make the charging circuit. I
specifically don't want to use an external NiCad charging chips - I don't
see the point (nor want to go to the expense) since there is already a PIC
in the circuit capable of doing the work.

I haven't been able to find any circuits or mentions in the PicList
FAQ/archives or on the web of this being done? Has anyone done it
sucessfully? Details?

John


_______________________________________________________________________
John Brown                         Email: john.brown@anu.edu.au
Mobile: 0429 455 504                 Web: www.netspace.net.au/~jabrown/

I don't want to sound paranoid but I think I'm following myself around.
Everywhere I go, there I am! Sometimes I think it's going to drive me
around the bend, but at least I know I'll have company when I get there.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics