BQ78PL116: Temperature calibration not working well

Ted Ong

Part Number: BQ78PL116

I have few packs cannot calibrate correctly. Even i use known good temperature sensor to calibrate the cell 1 temperature offset always different from other cells.

Suppose the normal pack will get about -360 offset but the bad cell is about -90++ . In actual fact, the cell 1 temperature is recorded at 41.6'C even is in room temperature.

1)Why the BQ IC is not calibrating the packs? I attached the photo here.

2)what is the Max Min range for temperature offset?

over 7 years ago

0 Batt over 7 years ago

TI__Mastermind 42535 points

You can try to manually write the offset to see if it fixes it. We have not seen any issues with temperature calibration.

0 Ted Ong over 7 years ago in reply to Batt

Prodigy 205 points

how do we manually write the temperature calibration? i checked on technical reference manual , none of the method was stated.

Can you guide me?

0 Batt over 7 years ago in reply to Ted Ong

TI__Mastermind 42535 points

Hi Ted,

Because the systems engineers with this device are on travel, it will take some time to find out the process to write this. I was suggesting this based on my experience with the bq40z and bq20z parts which have writable registers. Please allow a week for us to respond.

0 Batt over 7 years ago in reply to Batt

TI__Mastermind 42535 points

Hi Ted,

Allow me a few more days to get back to you. I'm unfortunately not able to find an answer from my colleagues.

0 Batt over 7 years ago in reply to Batt

TI__Mastermind 42535 points

Ted,

unfortunately due to a lack of availability of an evm and an inability to test, I'm not able to help you in this matter. I apologize for the inconvenience.

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BQ78PL116: Temperature calibration not working well