You are absolutely correct!  It was late..
----------
D. Yates
piclist@nerdulator.net


-------- Original Message --------
You still need a diode across the relay. The built in diode does not=20
help.

George

......  I believe the TIP120 has a built in reverse diode, so that=20
would reduce part count to 2 (resistor, transistor).  If you use a=20
transistor without a built in breakdown diode then be certain to add=20
one or the inductive kickback from the relay will eventually fry the=20
transistor.

 ---------- D. Yates piclist@nerdulator.net

 -------- Original Message -------- >Can anyone recommend what they'd=20
use to switch 12V relays from a 5V PIC? >You'd >be looking at=20
something (FET?) with a 5V gate & rated current to, say, >300mA,=20
>maybe an Amp, I guess? Gotta keep the component count to a minimum=20
so don't >really want to use optoisolators.

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