• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 64 subscribers
  • Views 260 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.

BQ76940: E6PM

vaibh P
Intellectual 260 points
Part Number: BQ76940
Other Parts Discussed in Thread: BQ78350-R1, BQ77915

Hello,

i want to know how exactly the BQ76940 balances the cell and the functionality of CHG and DSG pins.

If suppose some cell exceeds the OV threshold than should i enable that particular cell in CELL_BALANCE register and then disable CHG and enable DSG ? Please explain in complete detail,

thanks in advance 

  • 0
    TI__Guru* 81035 points
    Hi Vaibh,

    The BQ76940 cell balancing feature is described in the datasheet and there is also a long section in this document that goes into more detail: www.ti.com/.../slua749a.pdf

    The CHG and DSG pins respond to fault conditions in the device (see the FET Driving section of the datasheet). If one cell exceeds the OV threshold, the CHG FET will automatically be disabled by the device.

    There are many different approaches to cell balancing. We normally recommend balancing during charge after a certain threshold voltage (for example 3.9V). This is because at lower state-of-charge the cells will show more voltage variation from cell to cell. If you want to see some example algorithms, I recommend reading the Cell Balance chapter in the BQ78350-R1 Technical Reference Manual (This is a companion controller that many use with the BQ76940.): www.ti.com/.../sluubd3d.pdf
    Also, you can view this video about the BQ77915 cell balancing feature which describes its algorithm: www.youtube.com/watch

    Best regards,
    Matt