BQ34Z100-G1: Average Power register issue

Hello,

Today's a holiday and no one is in the office. We will get back to you tomorrow.

Regards,

Nick Richards

Hi,

Are your voltage and current readings correct? Was the device calibrated? Average Power is calculated using the last 16 samples.

Regards,

Evan

Hi,

Yes, the voltage and current measurement are correct. Yes the BQ34z100 was calibrated ( voltage, current, temperature). 

Regard,

Mathieu

Hi Mathieu,

Can you send me a longer log file, maybe of a charge discharge cycle.

Regards,

Evan

HI Evan,

Please find the log find attached.

You can find at the end of the log file a comparison with the instantanious power (UxI), average power calculated by U x Iaverage and the average power from the BQ register. 

 Chg@16A_Dsg@0.2C_power_analysis.xlsx

Hi,

Thanks for the log file.

Is there any scaling being done?

Have you tried upgrading to the newest FW version? BQ34Z100-DEVICE-FW Firmware | TI.com

Regards,

Evan

Hi,

No, there is no scaling. 

No, I don't upgrade the firmware to R2 version. I prefer to keep G1 firmare for the moment. 
Do you have some explanation about this behaviour ? 

Best regard,

Mathieu

Hi,

I am not sure at the moment why your devise is functioning like this, I have not seen this problem before, but I assume there is an issue with your configuration.

What is your voltage divider value and are using an internal or external voltage divider?

I also recommend upgrading your FW.

Regards,

Evan

Hi,

Where is the register voltage divider ? I don't find it on the dataflash for BQ34z100-G1. 
We are not using external voltage divider.

I checked on other battery. We have the same behavior, the register "AveragePower" is different to Voltage x AvgCurrent. 

Regards,

Mathieu

Hi Mathieu,

Below is information from the TRM on the voltage divider parameter.

I would verify your application does not need a voltage divider and all parameters related to calibration are properly configured.

Regards,

Evan