> To make this more specific what I am driving is an RGB LED
> and an infrared LED. It looks like each of the 3 elements of
> the RGB LED wants 30 mA.  The infrared LED will be driven
> (oddly enough) with low power...call it 10 mA.
>
> So call it a total of 100 mA being potentially sourced/sunk by the
> PIC.  And 30 mA at each of 3 pins.

> My reading of the situation is that that is enough to require
> drivers, but low power ones like logic buffers...especially since
> this is a battery operated device, and I don't want to use more
> current than I really need...correct?

CMOS buffers will use very little quiescent current, certainly
less than any PIC except Dale's freak. I think you're right that
this power demand could be approachng the PIC's comfort
zone so a driver sounds like a good idea. You say the IR LED
is taking 10mA - is that an average for high-speed pulsing ? IR
LEDs can take a lot of current in short bursts (a few us) to get
a decent transmission range, but pulse driving like that is too
much for a CMOS gate, even though the average of 10mA is
within spec. Zetex (ZTX) transistors are far superior to "ordinary"
transistors and are excellent IR LED switchers

Because of the potential for power supply spikes. I'd suggest the
PIC Vcc is isolated from the LED's Vcc by a 100R resistor (or
supply each Vcc through a diode) and have a 100uF + 100nF
close to the PIC as a filter. Also protect Mclr from spikes with RC.
The LED driver's Vcc should have a 100uF (close to the gate and
LED as a reservoir to supply pulse currents) and 100nF

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