Rodent of Unusual Size wrote:
> 10 LEDs apiece, superbright white, 3.5VDC/30mA apiece.
> This is a ground-up project, so I'm going to build the
> power supply as well.  I intend to drive the LEDs
> through Darlingtons driven in turn by the PIC's outputs.

Why?  Even most jellybean NPN transistors will be fine for switching 30mA at
35V.  With the PIC running at 5V and a 4.3Kohm base resistor, you are only
asking for a gain of 30 from the transistor.  Everything is will within spec
with comfortable margin.


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