• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 389 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.

BQ78350-R1: Battery Mode CapM automatically changes from from 0 to 1

John Batikian
Prodigy 120 points
Part Number: BQ78350-R1
Other Parts Discussed in Thread: BQ78350

I am using the BQ78350-R1 Li-Ion Gas Gauge / Battery Management Controller with BQ7692000 AFE in a new design. I am currently working on calibration and configuration of the gas gauge in order to make a golden image for production and/or setup learning automation. I am using the EV2300 connected to the SMBs on my board to communicate with the BQ78350.

I noticed that CapM, under battery mode, automatically changes from from 0 to 1. This means that my full charge capacity is reported in mWh when I want to see mAh. How do I set this to remain constant?

  • 0
    TI__Guru 54715 points
    Hi John,
    CAPM is a control bit set by the host, it is not changed by the bq78350. Check for bus errors, bus collisions or unexpected writes to the register. The default CAPM value is 0, but is not cleared by a reset command. Power reset will clear the bit, it cannot be set to default to 1 after power cycle. The host must set CAPM if it wants to see power
  • 0 in reply to WM5295
    TI__Guru 54715 points
    Hi John,
    I missed the obvious, or perhaps it is not obvious. In the data memory, the SBS Configuration/Initial Battery Mode parameter allows setting the CAPM bit so that CAPM will default high on reset. Setting this bit and sending reset will cause CAPM to read high. If you set the data memory bit and turn off the board for some seconds before boot, CAPM will also read high. If you set the data memory bit but do not reset, or set the bit and quickly cycle power (without wait) CAPM will remain low.
    The host can still change the CAPM bit if it wants.
  • 0 in reply to WM5295
    Prodigy 120 points
    Thank you for the information.