BQ25619: It possibly to cut off the PMID's output to the VBUS when the devices during the boost mode?

Eric Shih

Part Number: BQ25619

Hi Sir,

As the title suggests, when I use a 3.7V battery to boost the voltage to 5V for the PMID output, without an external power supply, will there be voltage backflow from the PMID into VBUS? My software settings have Q1 disabled, so theoretically there should be no voltage in VBUS, but I can consistently measure a voltage of 2.8V. Is something wrong?

1 month ago

+1 Michael Emanuel35 1 month ago

TI__Mastermind 42175 points

Hello,

There is a reverse blocking FET between VBUS and PMID. There should be no voltage on VBUS. Do you have a lot of capacitance on VBUS, and is it decreasing over time? Please make sure it isn't being pulled from another node.

Regards,

Mike Emanuel

Power management

Power management forum

BQ25619: It possibly to cut off the PMID's output to the VBUS when the devices during the boost mode?