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TDP142-Q1: TDP142-Q1 about I2C Setting issue

Lawrence He
Genius 3135 points

Part Number: TDP142-Q1

Hi, Support Team

We saw the datasheet of TDP142-Q1 about PIN13 and Pin14 have two question:

Q1: "pull up this pin to the VCC I2C supply of the I2C controller "  should I external pull resistor with 1.8V?  if yes, any suggest resistor value?

q1.png

Q2: About I2C default speed is 1MHz?

 Q2.png

if any suggestion, Please advise me.

Thanks,

Best regards,

Lawrence

 

 

  • 0
    TI__Mastermind 23921 points

    Hi Lawrence, 

    Typically, I2C runs in 100 to 400kHz and that is also the case for this device. We can support up to 1MHz. 

    For I2C pullup, please use 4.7k pullup. 

    Best,
    J


  • 0 in reply to J
    Genius 3135 points

    Hi J,

    Thank you for your reply. Let me confirm the scenario as below:

    i2c_en ==> f = i2c enabled at 1.8V when rsvd11 = "0" and rsvd10 = "0". Otherwise, it is in GPIO mode (i2c disabled).

    So, to enable I2C at 1.8V, the following three conditions are required:

    (1) i2c_en = f (float, leave pin open)

    (2) rsvd11 = "0"

    (3) rsvd10 = "0"

    If yes, do pin 13 (test/scl) and pin 14 (test/sda) need a 4.7k pull-up resistor?

    Note:

    in Fast mode(400kHz) pull up resistor range is 620ohm to 2.2k, typical is 1.5k?

    in Fsst mode+(1MHz) pull up resistor range is 1.5k to 2k, typical is 4.7k?

    if any suggestion, Please advise me.

    Thanks,

    Best regards,

    Lawrence

  • 0 in reply to Lawrence He
    TI__Mastermind 23921 points

    Hi Lawrence, 


    Lawrence He said:

    So, to enable I2C at 1.8V, the following three conditions are required:

    (1) i2c_en = f (float, leave pin open)

    (2) rsvd11 = "0"

    (3) rsvd10 = "0"

    If yes, do pin 13 (test/scl) and pin 14 (test/sda) need a 4.7k pull-up resistor?

    Yes, this is correct. I advise to keep 4.7k for both modes of I2C.

    Best,

    J