Purpose of R2 10k resistor on the due

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hi,

as subject says purpose of 10k resistor r2 on due?  didn't make sense me unless requirement usb.

thanks

it discharges decoupling capacitors when power removed (probably chip reset reliably if
power reapplied after).  nothing usb think.

normally cmos chips not drain supply capacitors when power removed - in particular
when xtal oscillator stops power drain become low.  reset / brown out detection circuitry
may fussy how power rail(s) come on power (ie assume start @ 0v).

its practice (esp higher voltages) arrange large capacitors discharge when power removed
so not "live" during transport , storage - not issue @ 5v, as
a circuit designer matter of course.


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