• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 31 subscribers
  • Views 340 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.

TMP102: Serial Bus Address

Hao Wang14
Expert 4415 points
Part Number: TMP102

Hi Team,

TMP102 has different I2C address when A0 is connected to different pins as shown in the picture below.

What kind of circuit internally is used to have this function? Is there any app note about it? Thanks.

Best Regards,

Hao

  • 0
    TI__Guru**** 244380 points
    Hello Hao,

    There is no app note describing the circuit. When connected to SDA or SCL, the TMP102 monitors the change of level to decode the slave address. At the time of a valid transaction start, if the A0 pin does not change then GND or V+ is decoded based on the level. If the A0 pin changes, then it is compared against the SDA or SCL to decode the address.
  • 0 in reply to Amit Ashara
    TI__Expert 4415 points
    Hi Amit,

    If it works as described, will the first immediate read or write command become invalid when A0 pin is connected to SDA or SCL? Because it takes time to monitor the voltage change on A0 pin.
    So when we program to read or write, do we give extra time to let TMP102 to decode its address?

    Thanks!
    Hao
  • 0 in reply to Hao Wang14
    TI__Guru**** 244380 points
    Hello Hao,

    No the first read or write command will not be invalidated, as the address bits do not move in till the first SCL, whereas address mapping would be detected earlier than that.