BQ25898D: VBUS leakage

Ann_Lien

Part Number: BQ25898D

Hi expert,

Customer has an issue on VBUS leakage in battery only condition. VBUS leakage would be around 1V and PMID is 3.8V. They also dsiconnected front end and back end to make sure there is no other connection from VBUS. May I know if this situation is normal? Thanks!

Best regards,

Ann Lien

over 5 years ago

0 Ning T over 5 years ago

TI__Guru 57621 points

Ann,

Does the customer observe the behavior on the EVM or on the customer's board?

Thanks,

Ning.

0 ezhao over 5 years ago in reply to Ning T

TI__Genius 10240 points

Ann,

The PMID 3.8V should be normal as there is path from BAT à BATFET Q4 à Q2 body diode. For VBUS, you can connect a resistor to GND and find out whether it is a leaking path.

0 Mike Yu over 5 years ago in reply to ezhao

TI__Intellectual 2320 points

Hi Eric,

I told customer to add 100 ohm on Vbus, the Vbus voltage drop to 6~7mV.

They also try to short Vbus to gnd with wire, but after discharge the capacitor on Vbus, the voltage on Vbus will rise to 1V again.

However, the customer just wants to know that is it normal to have 1V on Vbus? They have enable the OTG function.

Best regards,

Mike

0 Mike Yu over 5 years ago in reply to Mike Yu

TI__Intellectual 2320 points

Hi Eric,

I also try on our EVM, but there is no voltage on Vbus. Then I told to the customer, they found out that the leakage voltage comes from another diode. I think this issue is solved, thanks for your help.

Best regards,

Mike

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BQ25898D: VBUS leakage