D. Yates wrote:
> I'd recommend a 2N3904 in a common-emitter arrangement, with a
> 1k resistor connecting the base to the PIC's output.  This should be
> good up to ~200mA output,

But the OP specifically said 300mA.

> if you need more swap it out for a power
> transistor like a TIP120.  I believe the TIP120 has a built in
> reverse diode, so that would reduce part count to 2 (resistor,
> transistor).

No, the diode is in the wrong place.  The diode must be accross the relay
coil, not the transistor.


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