> Ahah!
>
> The MOSFET gate has to get within 200mV or so of the 5V rail
> to make sure it is turned off.

That's what the internal pup in the MIC should take care of.
Note that the PortB pin is *tristated* in the "off" state
using the TRIS reg, not driven activily high (to 3.3V).


> Otherwise it could burn up, especially when the
> ambient temperature is high.
>
> (see the top left graph on page 4)
> http://www.micrel.com/_PDF/mic94052-53.pdf
>
> Suggest you use the one open-drain pin (RA4) and perhaps parallel the
> internal pullup with another resistor to the 5V rail that is
> much lower, something in the low k-ohms.

Why does they then say in the data sheet :
"The pull-up resistor ensures that the P-channel
MOSFET is OFF until actively pulled down."

What am I missing ?

What I'd like to know more about, is the actual setup.
What does MPALB and the view-window have to do
with this ? Al wrote that he manpulated PortB using the
view window, didn't he ?

Jan-Erik.

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