We plan to use usb0 as the Host interface to a cellular modem. The cell modem uses 3.3v. Using this configuration in previous design (different cpu) vbus was tied to 3.3 and the DP/DM lines were connected directly to the modem interface connector (there was no vbusdrv signal). Reviewing the AM4372 checklist as HOST vbus should be connected to 5V (where vbusdrv is used as the enable for the 5V power). Since our interface (usb0) isn't required to drive an external usb interface/connector I would like to know if I configure the pins in the following way will I have any problems:
DP/DM connected directly to the Modem connector pins
CE is a NC
ID is grounded
DRVVBUS (is an output normally connected to EN of a 5v source) – in our design we won’t use this signal so would be NC/float
VBUS (normally connected to 5v vbus power source) – we would connect to the 3.3v rail driving the modem via a cap to ground( 0.1uF)
According to the AM4372 spec vbus is good to run between 0-5.5v (with 5v being nominal) --- please advise accordingly
