BQ3050EVM-001: EVM calibration

Hello Shirish,

I am asking this specifically for EVM board only ( as it comes with the preloaded .senc file of 3S ). For bare BQ3050 we are already doing that.

Does change in golden image also changes the stored Calibration data in fuel gauge ?

Reason for asking is , we are not using High end SMU device for calibration...So, TI`s factory used SMU calibration could be better than ours hence do not want to rewrite it. 

Hello Shirish,

So you want me to read this data from newly received EVM ( TI calibrated ) and then reinsert it after uploading OUR golden image , correct ? 

  Regards

Thanks Shirish,

Do I need to do calibration , In case if I do not update senc file , but just update .gg ?

I would recommend programming average values, then read a senc file with these average values

Hello Shirish,

When you say average values , are you pointing out to the calibrated values  ( below image ) which is already stored into the EVM board sent from TI warehouse ? 

Okay Shirish,

here is my Understanding from this conversion , After purchasing new EVM board : 

1. First we will store this calibrated values in a file i..e. .gg file.

2. then , we will program our own .senc file ( golden image) into EVM board.

3. after that , Re-write calibration values , which we have stored at first step.

This way we will have calibrated values from TI and our own parameters set. Correct ? 

Thanks Shirish,

With BQEVSW software , is there any option to Write / read ONLY calibration parameter's (TAB) into/from .gg File ? I tried to find such option but not able to do it.

Also , pls. confirm that .senc file and golden image are just alternate name. No Difference in them.

Shirish said:

Yes, you can do that. Write only calibration values and nothing else from the gg file.

I was just referring to this statement. So, you mean , after exporting .gg File , Remove all data except calibration data , save it and then import that .gg (which has only calibration data ) after writing new golden image. 

Thanks ,

OR the Other way around is , we can keep EVM senc file from TI ( Not our Senc file ) as it is and Just import .gg  file  (Our parameter ) removing calibration parameter from it.

This way we can keep existing calibration parameter from TI and update out our parameter. As TI EVM comes with 3S battery settings while our is 4S configuration. 

Hello Shirish,

we tried above procedure and. Surprise to see that temperature is not calibrated in any of the EVM boards.

Found same on all 3 new EVM boards.

Okay.

So Only Current and Voltage calibration is done before dispatching EVM board. right ?

Oh, Shocked to hear that.

Because all the conversation was on understanding that EVM is well calibrated before dispatch.

Hello Bhupendra,

Just want to be clear. The IC is factory calibrated but not the EVM. The EVM is a reference design and the calibration error will not be large. Use bqEVSW to calibrate accurately. Taking an average from multiple boards is good for the golden image.