SLUSEG4B December 2022 – February 2024 BQ25628 , BQ25629
PRODUCTION DATA
Refer to the PDF data sheet for device specific package drawings
When the BQ25628 is in OTG mode, Q1 is off to block power from PMID to VBUS. BQ25628 uses two comparators to sense OVP during OTG mode. The PMID_OTG_OVP comparator monitors for an overvoltage condition at PMID (VPMID > VBOOST_PMID_OVP.) The VBUS_OTG_OVP comparator monitors for an overvoltage condition at VBUS (VVBUS > VOTG_VBUS_OVP.) Even though RBFET is turned off during OTG mode on the BQ25628, an overvoltage at VBUS may result in an overvoltage at PMID via propagation across the RBFET body diode.
If an overvoltage persists, the status is updated and the converter powers down into a fault condition. Overvoltage on PMID or VBUS will result in OTG_FAULT_STAT and OTG_FAULT_FLAG set to 1.
If VVBUS > VBAT+VSLEEP, BQ25628 will exit boost OTG and enter adapter qualification. If VBUS passes adapter qualification (poor source detection), it will then enter forward charging mode. Even though the VVBUS > VOTG_OVP overvoltage condition does not cause an exit from boost OTG, an adapter plugin will trip the longer deglitch of the sleep comparator, and BQ25628 will exit from boost OTG for this reason.