• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 64 subscribers
  • Views 798 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

BQ34Z100-R2: Setting of number of series cells for multi cell application.

toshiyuki.umetsu
Prodigy 90 points
Part Number: BQ34Z100-R2
Other Parts Discussed in Thread: BQSTUDIO, BQ34Z100-G1,

Hi Team.

Using battery is 8S1P LiFePO4. We faced the following problem at calibrating voltage.

  • When we set number of series cell = 1, voltage calibration is succeed and Voltage Divider is 29184.
    Flash Update OK Cell Volt = 2800 x 8 x 5000 / 29184 / 1 = 3838. This value can be set.
    However after change series cell count to 8,  voltage is displayed 65535mV (=overflow?) on bqStudio.

  • When we set number of series cell = 8, voltage calibration is failed.
    I believe it's the same issue as the thread below.
    ttps://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/802169/bq34z100-g1-voltage-calibration-cell-voltage-correction-is-beyond-allowed-range
    So I did voltage calibration at 1/number of series, cells and got Voltage Divider = 3648.
    Flash Update OK Cell Volt = 2800 x 8 / 3648 = 30701. This value could not be set. (Over 4200mV)
    However displayed voltage on bqStudio is correct.

Q. What value should I set for Flash Update OK Cell Volt, is the voltage per cell? Or do I have to set the Number of series cells to 1?

Regarts.

  • 0
    Prodigy 90 points

    Hi Term.

    I may have found the cause.

    Firmware version 0.16 (BQ34Z100-G1) does not have this issue. Number of series cells works by setting the number of cells. Scaling Factor was added in version 2.01(-R2), so it may be affected.

    However, I haven't found any documentation for using multi-cell applications for BQ34Z100-R2.

    We will try using the 0.16 version.(It indicates using BQ34Z100-G1)

    Battery type : 8S1P LiFePO4 (Multi cell application)  26V

    bqStudio :  Ver. 1.3.101

    FW Ver. Number of series cells VoltScale() Voltage Calibration Flash Update OK Cell Volt Voltage()
    v2.01 1 (Not match to reality) 1 Success. Correct Get correctly
    v2.01 8  1 Failed. - (Calibration failed.) Get correctly
    v2.01 8 1

    Success.

    (Specify voltage divide by

    Number of Series cells)

    Error

    (Too large value)

    		 Get correctly.
    v2.01

    1 (Calibration)

    ->

    8 (After Calibration)

    1

    		 Success. Correct

    Overflow

    (65535mV)
    v0.16 8

    -

    (Not exists)

    		 Success Correct Get correctly

    VoltScale() is 1 because battery voltage is less than 65535mV.

    Thanks.

  • +1 in reply to toshiyuki.umetsu
    TI__Genius 12215 points

        For 8s application, please use G1 version at present, a new version with this issue cleared will be released very soon. Sorry for the inconvenience caused