common pull-down of unused USB Pins In P1020

[hyoungkikim]

hello experts

my new design use P1020   and i don't use USB function

in  P1020  checklist     if USB pins are not used  they are pulled down by resistors

Data lines are 8 bit   so  i like to use common pull-donw resistor  ( only USB STP is pulled up)

is it ok ?   

thank you

[r8070z]

Have a great day,

It is not ok. Do not use common pull-down resistor. There may be condition when connected pins are actively driven. For example you can see in the P1020 data sheet that if the I/O power supplies ramp prior to the VDD core supply, the I/Os associated with that I/O supply may drive a logic one or zero during power-up.

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