Thread: (Earlier version of) Backup onboard charger not correct
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Unread 12-01-2007, 13:00
dcbrown dcbrown is offline
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Re: Backup onboard charger not correct
Must be referring to:

http://www.ifirobotics.com/rc.shtml

which has a link to:

Battery Charging Circuit (pdf) 1-9-07

Yeah, it doesn't look right. I'd expect a steering diode in the path from +12v to the backup battery? Right now there is only the zener diode trying to clamp off the 12v while the charge current from main battery is just being limited through the 43ohm 2w resistor. Maybe I've had a brain fade and its ok - but it doesn't look right it to me either.

Bud
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Last edited by dcbrown : 12-01-2007 at 13:15.