BQ25798: Reverse polarity protection for charger input

Rune Lundvall

Part Number: BQ25798

Hi

Can't find any information on how to protect the charger inputs (VBUS) against unwanted reverse polarity connections.
According to the datasheet the VAC input handles -2V max, so VAC needs protection.

Would this solution work (adding a serial resistor and a diode to the VAC input)?

Please review and feel free to propose alternative solutions.

over 1 year ago

0 Jeff F over 1 year ago

TI__Guru**** 166626 points

Hi Rune,

That circuit will not work because, during normal operation, VACx pulls a small current from input for the charge pump that drives ACDRVx. We haven't been able to find a viable reverse protection circuit for this IC due to VACx pin. The best advice I can give is to use a keyed input port that cannot be installed backwards.

Regards,

Jeff