BQ20Z95: IIC BUS data issue

Hello,

We've got the issue and escalated to E2E for more help as the link below, you could take a look at it:

e2e.ti.com/.../bq20z95-iic-bus-data-issue

Hi,

I jumped TCA9617 to connect MCU and battery, the issue still happened. so TCA9617 itself didn't lead to the issue.

I changed the two other batteries, the issue still happened again. that mean battery solder may not the issue reason.

I found the issue temperature keep are -273.05 and -272.55, no other issue temperature after I reduced the pullup resistor value.

I guess issue may cause by battery itself or MCU IIC PEC (packet error checking) function.

How to verify these two possibility?

Thanks.

Hi,

We've gave some updates to the expert and please see the link on E2E below in case needed:

e2e.ti.com/.../bq20z95-iic-bus-data-issue

Hi Cherry,

How to use bqStudio to log the data? we have EV2300 monitor the battery.

But we only found normal temperature as follow picture, no issue temperature record. is there others way to log temperature?

Thanks.

Hi,

On the Registers tab, there is a "Start logging" button. Choose a file and let it run for a few hours. Then you can check the log file temperature column data.

Hi Cheery,

I used EV2300 monitor the battery discharging and record the log file. Here I found follow issue in the log file.

1. 

about he "Possible Error-See error log" information. where can I see the detailed error information or error reason?

2.  you can see a time interval in the below picture, I found several place data discontinuity in the log file. what's happen? is it a issue or normal situation?

Thanks.

Hello,

We will consult with our expert and get back to you early next week.

Thanks.

Hi,

bqStudio has a scan interval of 4 seconds for registers by default. Looks like this was changed.

Hammering the gauge with communication can leave the gauge with not having enough time to perform simulations. We will need more data to know if the gauge entered an unresponsive state where there is discontinuity in the log. Can you provide more details on what bqStudio settings/selections were changed while taking the log?

Infrequent communication errors are normal. These must be retried in the real system. You can get details of communication in another file that is in the same location as the log file. It should have "err" in the file name.

Hi Cherry,

Please see bqStudio setting information, we only monitor real-time temperature.

Set scan cycle is 1 second, log cycle is 1 second.

Please see our log file there is a error record

My question is what's this message meaning? is there no data be measured？ what information be sent to out MCU at this situation?

I saw in the log file, there are "Sample" number and "Elapsed(s)" number, at the beginning, the Elapsed(s) number = Sample number, but as the time fly, the Elapsed number become much bigger than Sample number, could you explain what's reason and what happened?

Thanks.

Hi,

We've created a new thread regarding your follow-ups since the original post had been long time ago, you could also take a look at the link below:

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/1134321/bq20z95-iic-bus-data-issue

Hi,

Could you send us the entire log file? We also are curious why samples are taking 1s in the beginning and what appears to be around 1.4s as the file goes on.

Hi Cherry,

FYI.

Please note: I changed the time interval from 3 second cycle to 1 second cycle at first file at the monitor beginning stage.

907 22 03.log9141102.log

Thanks.

Hi,

Thanks for your info and please expect the response.

Hi Cherry,

Very thanks your support.

I have a question is when our CPU (host) read data from battery, but battery has error happen at this time, like log file record: no data present, what data will be read by our CPU (host)?  0x00, 0xFF, or others random data or last measure data?  is there rule of the battery communication protocol define this condition?

Thanks.