On Thu, Feb 23, 2006 at 11:22:16AM -0800, mchristisen wrote:
> 
> Ok, did some more looking. Forward Voltage rating is the voltage drop. So if
> I have a 1.6V LED and a 5V source I subtract 1.6 from 5 and divide by the
> current rating to find that I need a 170ohm resistor. Damn, feel like an
> idiot on that one.

You nailed the solution. No idiots here.

> 
> 
> So, do I run a PIC output close to its max. sink rating (25mA in my case) to
> direct drive an LED at 20mA or should I increase the resistor to get around
> 15mA?

Never drive a pin near its absolute rating. Thrown in a 220 ohm and keep the
current under 15ma.

BAJ
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