• State
  • Locked Locked
  • Replies 4 replies
  • Subscribers 62 subscribers
  • Views 288 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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:

BQ76952: Some question about 76952

BQ76942: There is some question when I use the IIC communication of bq76942.

Tan Haitao
Prodigy 210 points
Part Number: BQ76942
Other Parts Discussed in Thread: BQ76952

Hi：

I have try to use the subcommand read DEVICE_NUMBER - 0x0001 with iic , but the iic communication is  unstable.

The bq76942 do not answer the ACK  In most cases.

The screenshot of my oscilloscope is shown below:

I try to send device address 0x10 to the bq76942,but there is no ACK send to me. 

But sometimes the  76542 will give back the ACK signal of the command.

Anyway, this chip's ACK signal is Very unstable, The chip is so unstable that I can't complete a iic communication.

Is there anything wrong with my wavefrom?  If not, What else needs to be done?

Dose this chip has a IIC clock strech function?

  • 0
    Prodigy 210 points

    I try to use the same MCU and same code to control bq76952 with iic interface.

    Communication is stable, bq76952 can provide ACK signal stably.

    A screenshot of the logic analyzer is shown below.

    Is there some different between the bq76952 and bq76942?

    Or is there some unknown problem with my bq76942?

  • 0 in reply to Tan Haitao
    TI__Guru* 77283 points

    Hi Tan,

    These 2 devices should behave exactly the same. The I2C is identical for both devices. Maybe there was something unstable or noisy in your first setup?

    Best regards,

    Matt

  • 0 in reply to Matt Sunna
    Prodigy 210 points

    Please give some helpful information, is there any bug about the I2c of 76942. when I use the  76952, I also find some problem about the I2C, after try many times,your fae told me the I2C has bug,which make me crazy.

    I find many people ask the I2c， I guess you'd better give some document about the I2C.

  • 0 in reply to Tan Haitao
    TI__Guru* 77283 points

    Hi Tan,

    There is no bug on the BQ76942 I2C. Please let me know exactly what you were told by the FAE.

    Also, please let me know specifically what problems you are having with the BQ76952 I2C. It is difficult to help you without more detailed description. 

    Best regards,

    Matt