Darren Gibbs wrote:
> I also have a couple of beefy solenoids that
> draw about 1.6A and have found that they fry the TIP120 even with
> very short pulses (~1ms).

Do you have reverse diodes accross the solenoids?  I'm guessing not, and
that the inductive spike when turning the solenoids off is actually what is
frying your transistors.

> I tried putting two TIP120s in parallel to
> handle the extra current,

Bipolar transistors don't parallel well.  What are the max collector
current, max collector-emitter voltage, and gain specs of your transistors?
Also show your circuit.


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