• State TI Thinks Resolved
  • Locked Locked
  • Replies 6 replies
  • Answers 1 answer
  • Subscribers 30 subscribers
  • Views 564 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.

TLV320DAC3101: Clock stretching function

Ryuuichi machida
Guru 13335 points

Part Number: TLV320DAC3101

Hello,

I would like you to ask about function of I2C clock stretching.

* I understand that TLV320DAC3101 have clock stretching function for I2C.

However, I would like you to confirm whether there is timeout for clock stretching or not.

If no, how much time should host controller wait to perform device reset via RESETn pin ?

Best Regards,

  • 0
    TI__Guru** 114505 points
    Hi Machida-san,

    What do you mean by timeout? The max frequency is 400kHz so I think if the device is not able to sync with master during this period the communication would not be possible.
    Regarding the RESET, what time do you mean?

    Best regards,
    -Ivan Salazar
    Applications Engineer - Low Power Audio & Actuators
  • 0 in reply to Ivan Salazar
    Guru 13335 points

    Hello Ivan-san,


    > What do you mean by timeout?

    What I want you to confirm is below.

    * Internal function observe clock stretching condtion. And if clock stretching condtion continue certain time, internal function release clock. This means watchdog timer function for clock stretching.("Timeout" mean watchdog time function.)

      I would like you to confirm

    1. This device have i2c clock stretching function, right ?

    2. Is this device have above function such as watchdog time ?

    Best Regards,

  • 0 in reply to Ryuuichi machida
    TI__Guru** 114505 points
    Machida-san,

    I'm no very experienced on clock stretching, but from what I understand, the stretching condition is given when slave is not as high speed as master, so master waits for slave to release the clock signal. Thus, from my understanding, the watchdog would be present on the master, not on the slave side. TLV320DAC3101 can only work as slave for I2C.

    There is no mention of clock stretching function in the device information, although as an I2C standard the device might be able to do it.

    Best regards,
    -Ivan Salazar
    Applications Engineer - Low Power Audio & Actuators
  • 0 in reply to Ivan Salazar
    Guru 13335 points

    Hello Ivan-san,

    >from my understanding, the watchdog would be present on the master, not on the slave side.

    No, SCL is forced to low by slave when clock stretching is performed. So need to release SCL at slave side.

    (This means there is case which watchdog is implemented at slave side, and reset device itself.)

    Anyway, what I want you to confirm is "TLV320DAC3101 have clock stretching function or not" at first.

    Another FAE said that "AIC" family  have clock stretching. Therefore, we believe that this device also have this function. However, as you said, there is no description about this function in datasheet.

    So, I asked you just in case. Could you please confirm designer ?

    Best Regards, 

  • 0 in reply to Ryuuichi machida
    TI__Guru** 114505 points
    Hi Machida-san,

    We have contacted our design team about this. I'll come back to you with further information once they have answered.

    Best regards,
    -Ivan Salazar
    Applications Engineer - Low Power Audio & Actuators
  • 0 in reply to Ivan Salazar
    TI__Guru** 114505 points
    Machida-san,

    The device will pull SCL down during SDA data/ack phases. Master cannot operate I2C faster than what is spec in the slave device data sheet (TLV320DAC3101).

    Best regards,
    -Ivan Salazar
    Applications Engineer - Low Power Audio & Actuators