> .....  I believe the TIP120 has a built in
> reverse diode

It has, but if that diode is used to take the switch-off peak from a
coil the current will end up in the power/ground rail. It depends on the
load, capacitors etc. whether that is acceptable.

Wouter van Ooijen

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Van Ooijen Technische Informatica: www.voti.nl
consultancy, development, PICmicro products

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