Hi all,
I hope there is an anolog person out there that can point me in the right
direction.  I have a circuit where it is powered by a Nimh 24V battery.  The
+ rail is the ground reference and the - terminal is the -24V rail with
respect to ground.  I use a DC/DC converter to generate the +5V rail.  This
of course is what is powering the PIC, 16F877, and I would like to be able
to read the battery voltage to determine when its time to recharge.  Its a
Nimh 24V pack, and at 20V I would like to display the need to recharge.  I'm
not sure how to do a level shift to where I can read the voltage into the
A/D.  I was thinking about an opto isolator, I'm using a CNY17 in my circuit
and could use another if it would do the job.  Any other solution is
certainly welcome.  Thanks for any help.
Thanks,
FJ

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