BQ40Z50-R2: After discharging for a while, there are many abnormal protections for the equipment

Hi Ian,

It seems like the temperature reading is extremely high here, can you please confirm whether there is anything connected to the TS1 - TS4 pins at this time?

If not, it seems like the gauge is still processing the reading from this pins. Please disable them in the Temperature Enable register.

Regards,

Anthony

Hi Anthony，

My battery pack uses TS1 to collect the surface temperature of the battery cells, not TS2~TS4. Now, after clearing the PF fault position through Battery Management Studio and discharging it again, this abnormal situation will be repeated every 2-3 minutes of use. In addition, I did not turn on UTD and OTD protection, nor did I enable PF protection. These can be read from the gg.csv file, but after the abnormality occurred, many PF fault positions appeared. Please assist in analyzing this abnormal phenomenon. Thank you!

Hi Ian,

Is this being done in a temperature chamber? If the device is being applied to a temperature greater than 85C we cannot guarantee correct functionality.

Is there any difference if the golden image .srec is reloaded to the device?

Regards,

Anthony 

Hi  Anthony，

My battery pack is used on drones, which is an abnormal situation that occurs during normal outdoor flight. Upon inspection, it was found that the battery gauge had various abnormal protections. After clearing it, it can also be reproduced by simulating discharge in an indoor environment, as shown in the attached log. Therefore, the temperature environment was normal throughout the entire process. The temperature of the log data suddenly changed from 27 ° C to 192 ° C, and after continuous collection, it suddenly changed from 192 ° C to 27 ° C. This should be an error in NTC data collection, as the internal temperature collection is correct. So the problem is not with temperature, what is the main reason for other PF abnormalities?

Hi，After this battery pack was left idle for a period of time, it was found that there was a DFW setting. According to the specification sheet, it says' Data flash write not successful '. Why did this cause this, and I cannot use the PF_CEAR command to clear the PF flag anymore

Hello Ian,

The gauge's data flash wore out from being flashed to many times or was damage from an ESD event. Once this happens, the gauge will permanently disable the pack. There is no recovery and it is recommend to do rework on the pcb and replace the IC.

Thank you,
Alan

Hi，ESD causes flash abnormalities in the battery meter, whether it is caused by ESD coming in from the I2C interface, B+, or P+. Specifically, what network ESD is causing flash damage

Hi Ian,

The DFW flag only specifies that the Data Flash write was not successful from the physical level. The device is not able to decipher which pin an ESD event has affected. Are there any exposed connections in this system that could give us an idea how this occurred?

Regards,

Anthony