• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 64 subscribers
  • Views 251 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.

BQ27427: How to correctly connect the power consumption monitor with the charging IC BQ25619E?

Emma
Prodigy 60 points

Part Number: BQ27427
Other Parts Discussed in Thread: BQ25619,

Tool/software:

When using the fuel gauge chip BQ27427 in conjunction with the charging chip BQ25619, should the SRX pin of the BQ27427 be connected to the BAT pin or the VSYS pin of the BQ25619 to achieve battery level detection? Could you please check if there are any issues with the schematic diagram?

  • 0
    TI__Guru** 106205 points

    Hello Emma,

    Yes, you would connect the output sense line (SRX) to the BAT pin of the charger, not SYS.

    Based on what I can see in the snippet, I'm not sure if the TS biasing network is correct, I see 2 10k resistors, normally for our recommended NTC this is 5.3k and 31k. Also the QON does not need an external pull-up. it has an internal pull-up already.

    Sincerely,

    Wyatt Keller

  • 0 in reply to Wyatt Keller
    Prodigy 60 points

    Thanks for your answer. I have changed the NTC resistors to 5.3K and 31K. There is another question for consultation: Can the BIN pin of BQ27472 be connected to the TS pin of BQ25619 and together connected to the NTC thermistor terminal of the battery? What problems might occur? The specification doesn't particularly explain the role of connecting the BIN pin to the NTC. What is the function of such a connection?

  • 0 in reply to Emma
    TI__Guru** 106205 points

    Hello Emma,

    The gauge and charger cannot share the same thermistor, their biasing networks will interfere and will provide incorrect temperature measurements. We recommend to use the gauge temperature measurement and adjust the charging profile as necessary with the host.

    Sincerely,

    Wyatt Keller