• State TI Thinks Resolved
  • Locked Locked
  • Replies 7 replies
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 271 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

BQ27441-G1: GPCCHEM Report Questions

Rob Kuschinsky
Prodigy 30 points
Part Number: BQ27441-G1
Other Parts Discussed in Thread: GPCCHEM, BQ28Z610, BQSTUDIO

Hello,

We're using the BQ27441DRZT-G1A fuel gauge in one of our products.  We recently had to change our battery cell to a different manufacturer.  I ran a relax, discharge, relax test and submitted the files to the GPCCHEM calculator to see if it will still work with our gauge.  The report showed that the best CHEM_ID match for my battery is 2144, the BQ27441-G1A has a CHEM_ID of 0x0128.  It also shows the following error for the 3 ROM based gauge families:

Warning: Generic ID Deviation is so high that it is most likely due to anomaly in the data. Please check that data files have recommended format, units and test schedule

I checked the format of my files and feel they adhere to the requirements called out in document SLVA725A.  

I've attached my data files and the GPCCHEM report.  Do you see anything wrong with the data files?

Thanks,

Rob


BQ27441-G1A#1.zipBQ27441-G1A#1-report.zip

  • 0
    TI__Genius 13575 points

    Hi Rob,

    Looking at the report file you sent, the closest choice is the 2144 ChemID match, however, for this ChemID you will need a data flash gauge. I believe that if you are trying to get a ChemID with a smaller error percentage, you might need to chose a different cell.

    Regards,

    Anthony Baldino

  • 0 in reply to Anthony Baldino
    Prodigy 30 points

    Anthony,

    So there's no way to adjust the BQ27441 parameters to make it work with this cell?

    If not, can you suggest a data flash gauge that has parameters (single cell 5000mAh, I2C interface, external sense resistor, VSON12 package, same pinout) similar to our existing gauge, BQ27441DRZT-G1A, or make a suggestion, or two, for our best option?

    Thanks,

    Rob

  • 0 in reply to Rob Kuschinsky
    TI__Genius 13575 points

    Hi Rob,

    For the bq27441, the ChemID is preconfigured so even with changing the parameters, the gauge will still not function properly.

    The closest data flash gauge I could find with these requirements is the bq28z610, which meets all the requirements other than having a different pinout.

    https://www.ti.com/product/BQ28Z610#product-details 

    Please let me know if this doesn't fit your requirements and I can find other options.

    Regards,

    Anthony Baldino

  • 0 in reply to Anthony Baldino
    Prodigy 30 points

    Anthony,

    I forgot to mention that I need a system side device.  It looks like the BQ28Z610 is a pack side device.  Is there another IC you could recommend?

    Thanks,

    Rob

  • 0 in reply to Rob Kuschinsky
    TI__Genius 13575 points

    Hi Rob,

    I talked to our team about this issue and this is the information I received:

    Regarding your GPCCHEM report, if you are ok with the high DOD error, the bq27411-G1C allows you to keep the same package, pinout, and your other requirements. Although it says its a pack side gauge, most of our gauges can be implemented on either the system or pack side.

    If you are looking for a higher accuracy, then the bq28z610 will allow you to use the ideal chemID from the report. Although most of the time data flash gauges are implemented on the pack side due to pack side implementations needing to be more accurate, they can be implemented pack side.

    Please let me know if this helps.

    Regards,

    Anthony Baldino

  • 0 in reply to Anthony Baldino
    Prodigy 30 points

    Anthony,

    Thanks for the information.  I have a couple more questions. 

    My current fuel gauge, BQ27441-G1A, has a pre-configured CHEM_ID of 0x0128.  When I look at the list of CHEM_IDs in BQstudio it indicates that the chemistry for that ID is LiCoO2, see below.  The same chemistry as the bq27411-G1C that you suggested.  Is there a way for me to find out what the theoretical DOD error would be for the bq27441-G1A part?  Would it be the same as the alternative with the CHEM_ID of 128, the bq27421-G1A at 28.79%?  I'd like to be able to compare my current gauge error with the suggested one to see if it's worth switching.

              

    Thanks,

    Rob

  • 0 in reply to Rob Kuschinsky
    TI__Genius 13575 points

    Hi Rob,

    The max DOD error that is found on the report is comparison between the cell you are using and the ChemID containing the information for a different cell. So in this case, using the ChemID #128 that is found on your bq27441-G1A would give you the DOD error of 28.79%.

    However, please note that the Impedance Track Algorithm will not function properly with a ChemID with over a 3% DOD error.

    Regards,

    Anthony Baldino