• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 230 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: BQ7694001DBT

Ken Jewell1
Prodigy 40 points
Part Number: BQ76940
Other Parts Discussed in Thread: BQ78350, EV2400, , BQ78350-R1A

Hello,

With the BQ7694001DBT is there any way to get the cell balancing outputs to switch in sequence for a production test to show the circuit is working?

Thanks

Ken

  • 0
    TI__Mastermind 27321 points

    Hello Ken,

    The host is responsible to write an algorithm to test all cells. You can activate cell balancing in each cell one at a time. To test if cell balancing is working, you can probe or measure on the scope each VCx pin. Usually the voltage will drop at the VCx pin of the actively balancing cell. If using external balancing circuitry, you can measure the voltage drop on the balance resistor (if it's working, it should measure nearly the same voltage as the cell voltage).

    To activate a particular cell balancing channel, simply set the corresponding bit for that cell in the CELLBAL1, CELLBAL2, or CELLBAL3 register. For example, VC1–VC0 is enabled by setting [CB1], while VC12–VC11 is set through [CB12].

    More details on Cell Balancing in section 8.3.1.3.3 Cell Balancing of datasheet. Also, this BQ769x0 family devices' FAQ covers a cell balancing section.

    Hope this helps!

    Regards,
    Jose Couso

  • 0 in reply to Jose Couso
    Prodigy 40 points

    Sorry, I forgot to say that the interface is connected to a BQ78350 so the CB1 .. CB12 registers are not exposed on the bus connected to the EV2400.

    Is there any way to do what I need in this configuration?

    Kind Regards,

    Ken

  • 0 in reply to Ken Jewell1
    TI__Mastermind 27321 points

    Hello Ken,

    The BQ78350 will act as the microcontroller if using it along with the BQ76940. The BQ78350 is a companion gauge and has its own cell balancing algorithm.
    By using the BQ78350, the user will loose the host controlled flexibility of the BQ76940 when balancing. For more cell balancing flexibility and control, an MCU can drive the BQ76940.

    On another point, if you want to use the BQ78350, I suggest getting the BQ78350-R3 version instead of the BQ78350-R1A. The R3 version allows cell balancing during relax mode, whereas, the R1A only does cell balancing only during charging.

    Regards,
    Jose Couso