On Tue, 29 Oct 2002, Herbert Graf wrote:
>         Yes, for the above reason, the PIC outputs are NOT current limited by
> design, and certainly don't limit themselgves to only 25mA. TTYL

But when you say that, you make it sound like there could be infinite(and
damaging) current flow.

Let me point out that the PIC has internal resistance (which varies
depending on power supply voltage and pin polarity, among other things)
which does, in fact, lead to a predictable limit on output current.

If you connect a PIC output to ground and try to drive it high, excessive
current will flow. However an LED connected to ground is not ground. The
voltage drop of the LED and the PICs resistance will limit the current to
under 25 mA.

-Bob

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