> I understand that 5 volt PICs work with what seems low
> voltage and limited current.  Is it a good idea to put some
> sort of electrical "fusing" between a regulated 5 volt power
> supply and the PIC input pin(s)?  (There is a 3 Amp circuit
> breaker in the upstream 12-16 volt power supply that I
> regulated down to 5 volts.)  Would it serve to protect the
> PIC, associated components, and possibly safety?

Not sure why you would want to put some sort of "fusing" between the supply
and the input pins. The supply should be connected to only the power pins on
the chip.

normally there would be some sort of pull up or pull down resistors on input
pins, or some sort of equivalent (relatively) low impedance in the form of a
gate or some other electronics that is driving the input.

In certain instances it is necessary to use protection diodes to ensure the
input pin does not go outside the power supply pin voltages. In this case
there will be a series resistor from the signal source voltage to the input
pin.

--
http://www.piclist.com hint: To leave the PICList
mailto:piclist-unsubscribe-request@mitvma.mit.edu