al smith wrote :

> I have a design where I am using a Micrel MIC94053 (internal
> pup) to switch 5V.  I am driving this from portB:2, and it doesnt
> seem to want to drive it low enough (best way to describe it I suppose).
> In that if I tie the gate to ground, the circuit works fine.  If I drive
> from Port D, it works fine. I have the bit set low in the PORT reg,
> and use the TRIS to enable/disable it.  I've verified that when I
> do this, it does go tristate and does goto a logic level low (0 V
> on the meter) but it can't seem to force the FET to turn off.
>
> Are there limitations to using port B?

What PIC ?

If the pin is at 0V, it is at 0V, It does not "drive" anything
if there isn't a source of current from a higher voltage. There
should be no different between grounding the MIC-input and
connecting it to a PIC pin that is at 0V (if it is...)

Jan-Erik.

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics