(I) writes:

> 1) Aren't the N-FETs upside down? 

ARGH!  Yes.  Thank you for spotting that.

> 2) I haven't looked up the gate charge on the FETs

About 2.2 nC at our operating point.

> I like to use a resistor between the uC and the FET gate (keep
> pulldown on uC side). It limits the current draw on the pin, controls
> rise time, cuts ground bounce, yada yada. It may not be necessary
> here, as I'm usually driving PWM, and you are (most likely) not;
> however, it's cheap insurance to protect the uC output.

I don't think it's necessary.  But after talking to Keith, we'll add 
the footprints.  We've got the space and I've got to rework that part
of the board to fix the D/S swap anyway.

> 4) Does anyone know what the LTC1682 or LP2980 does when it sees
> reverse voltage on the input? A schottky diode or a PFET might save a
> bunch of parts if someone connects the battery backward.

I don't know what the regulators are going to do in that circumstance, but
I hate to take the voltage drop hit on a 3.7 volt nominal battery system 
where run time in the post-landing search phase could be important.  We
mitigate the risk of mis-connection by using the JST standard polarized
battery connector for the LiPo cell.

Thanks for the feedback!


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