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Original question:

ADS1261: IDAC accuracy specification questions

ADS1261: IDAC accuracy MAX-MIN specifications

user6505359
Prodigy 10 points
Part Number: ADS1261

Hi, I have a question about the accuracy of IDAC(MAX-MIN).

The IDAC accuracy is ±4%(Ta -40℃ to +125℃).

However, in the data sheets Figures 42-45, the IDAC accuracy is probably around ±0.7% at all temperatures.

Under what conditions does IDAC accuracy decrease?

I want a constant current of 100uA with an accuracy of 1%.

I am wondering if I can use this IDAC conditionally.

  • 0
    TI__Guru 52576 points

    Hi User,

    The IDAC accuracy tends to get worse over temperature (the absolute drift spec is 50ppm/C typical), and as you can see from the figures it also gets worse the closer you get to the compliance voltage.

    In general, the IDACs are not meant to be used for their absolute accuracy, but instead used as part of a ratiometric system where the sensor excitation current is also used to establish the ADC's reference voltage, and therefore cancels out. For this reason, the IDAC absolute accuracy has wide margins.

    -Bryan