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BQ76940: Cell balancing relaxation time before cell voltage

Part Number: BQ76940
 Before  balancing on ,Cell balancing relaxation time is 12.5ms?It's a little long. It affects the speed of the MCU processing.,Pls  Help check the time?
Whether it is possible to  two ways open balancing?We are Single way Open now!
  • Hi ,
    One of our BMS experts has been assigned to your issue and will answer shortly.

  • Pls help me quickly !thanks!

  • Hi User,
    It looks like you had some attachments which do not show up, so I may not understand the question.
    Yes, the cell balancing relaxation time is fixed at 12.5 ms and is not adjustable. After the relaxation time the part begins to measure the bottom cell in the cell group. This happens independently in each group of the bq76940.
    The sequencer in the bq76940 controls the timing of the balancing including the relaxation and measurement. The MCU should respond much slower to set the cells to be balanced and stop balance at an appropriate time, this should be much longer than the 250 ms scheduler time. Realize the MCU is operating asynchronously to the bq76940. When the balance register is written it is asynchronous to the timeline of the scheduler and must be synchronized to the scheduler to adjust the timing of the next scheduler interval for balancing. If the balance register write just missed the start of the interval, it may be 250 ms before balancing begins. Balancing will typically need to run for some seconds before meaningful capacity adjustment is achieved.