BQ25601: VAC OVP specification

Paul Yeh

Part Number: BQ25601

Hi expert,

I check bq25601 datasheet and find its VAC OVP defaul is 6.5V. I would like to double check is it fixed or automaticly adjust based on input voltage source?

If this value is fixed, I am afraid that if I plug in 9V adaptor for bq25601 then I think the system won't power on in dead battery condition.

Please advise am I right? And any suggestion for this situation?

Thank you and Regards

over 8 years ago

0 Bill Schepers over 8 years ago

TI__Prodigy 150 points

Hi Paul,

You are correct, the default for VAC OVP is 6.5V, and it does not adjust automatically based on the input voltage source. If the device is in VAC OVP, then the system will not power up if there is no battery attached or if the battery is dead. Also, if the device is in VAC OVP, then it will not communicte via I2C.

If you want to change the VAC OVP setting, then you will need to reduce VAC to below the default OVP threshold (6.5V) to be able to communicate via I2C. You can change VAC OVP by setting REG06[7:6]='10', which sets the VAC OVP to 10.5V (recommended for a 9V input), or set REG06[7:6]='11' to set VAC OVP to 14V (recommended for a 12V input).

I hope this answers your question!

Bill Schepers

0 Paul Yeh over 8 years ago in reply to Bill Schepers

TI__Genius 16185 points

Hi Bill,

thanks for feedback. and I think I understand behavior.

Best Regards

0 Jason Petras over 8 years ago in reply to Bill Schepers

Intellectual 650 points

Hi Bill,

This is a pretty big problem for the part - at least if it is advertised as 9V, 12V capable without this gotcha being called out in bold text. Is there going to be a fix? I have this part half designed in. I would like to use it with a 9V input, but now have to throw it out. Is there some hope here?

Thanks!
Jason

0 Ning T over 8 years ago in reply to Jason Petras

TI__Guru 57781 points

There is another thread about the topic. Please refer to https://e2e.ti.com/support/power_management/battery_management/f/179/t/618989. Thanks!

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BQ25601: VAC OVP specification