• State TI Thinks Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 241 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.

Original question:

BQ40Z50: Coulometer BQ40Z50 The I2C communication is abnormal

BQ40Z50: Slave I2C signal abnormal.

LukeMC Tsai
Prodigy 60 points
Part Number: BQ40Z50


I'm in the same situation, and here is my pics.

Host is CPU and Slave is BQ40Z50.

Due to this pics I think BQ40Z50 can't response at correct high and low level signal.

Please leave your comments here, thank you.

  • 0
    TI__Guru 57697 points

    Hello Luke,

    The communication lines are pulled up by default and the bq40z50 can only pull it down. There must be some other voltage source on the bus or there is some kind of resistor divider being formed that is resulting in this waveform

  • 0 in reply to Shirish
    TI__Guru** 105870 points

    Hello Luke,

    To add to Shirish's comments, it is common that the line resistance may be too high causing that voltage divider type issue, especially if your pull-up are set too low. Try decreasing your line series resistance and the pull-up strength.

    Sincerely,

    Wyatt Keller