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DS90UH926Q-Q1: Value of Ration at IDx Pin out of specified values

Walter Keller
Prodigy 40 points
Part Number: DS90UH926Q-Q1

I'm looking for an answer to the following question:

In case of an error in the BOM there are produced a lot of PCB with a Ratio at IDx Pin wich is not in the table:

Actual voltage is 2.5V instead of 2.399V. This is beyond the linit of the table Is the address 16 then still valid ?

If not we have to rework many boards

Thanks

  • 0
    TI__Genius 10475 points
    Hello,
    We received your query and we are looking into it, we should have an answer soon.
  • 0 in reply to Palaniappan Manickam
    TI__Genius 12705 points
    Hello Walter,

    It is important to closely match the voltage ratio as in most cases there is limited range for the correct address across temp range. I am not sure what is the 2.399 value you are referring to, the targed ratio for the resistors to hit mode 16 woudl be R1/R2 = 0.47 .
    It is also possible to force the I2C address to the desired value by I2C programming of register 0 if desired. This would be potential SW work around.
  • 0 in reply to Liam Keese
    Prodigy 40 points
    Hello Liam,

    is there a upper Linit for the voltage, we have done tests and the address worked also with just a pullup resistor.

    For your workaround, how can we access the register if the adddress is not set correct ?
    Regards,

    Walter
  • 0 in reply to Walter Keller
    TI__Genius 12705 points
    Hello Walter,
    In order to reset the I2C device address you would need to program using the initial value, then set to the desired value during setup. This would need to be done each power cycle at initial startup. As there is limited address options it would be based on what response was received when reading back from the device.
    It is likely the device will operate correctly pulled up to Vdd, however this condition is not production tested and cannot be guaranteed.

    Regards,
    Liam