AVR-Chat

> Here's a better diagram as to what's going on with the reverse
> protection:
> 
> http://i5.tinypic.com/20hrl1i.jpg
> 
> Again, ignore the P-channel.  I just can't figure out how to have both
> reverse polarity and overvoltage protection.

Where's the problem ?
As you've drawn it, D2 is across the inductor. Just where it should be. 
You said that the wiring to the inductor is integral to your unit so the only 
place you can get the polarity reversed is at the "+12V In" node. There's no 
hinderance there unless you have drawn the circuit wrong and the inductor 
is connected to  "+12V In".

Steve.


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Steve Baldwin                          Electronic Product Design
TLA Microsystems Ltd             Microcontroller Specialists
PO Box 15-680, New Lynn                http://www.tla.co.nz
Auckland, New Zealand                     ph  +64 9 820-2221
email: steve@tla.co.nz                      fax +64 9 820-1929
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