Part Number:ADS131A04
Hello
We have a design with an ADS131A04. This is supplied with +/- 2.5V. We use the internal reference of 2.442V. Look at the schematic below.
We have a lot of systems they are working fine, but now we have found a deviation in the reference voltage for a number of ADCs from batch code 83TG4 / AC56.
In the datasheet an accuracy of 0.1% is specified.
We measure a voltage between 2,450V and 2,460V between the RefP and Refn pins.
After replacing the ADC with a sample from another batch, it is good (measured 2,442V).
Not all ADCs in batch 83TG4 / AC56 have this problem, we also have ADCs with batch code 83TG4 / AC56 within specs.
We have not yet seen whether this deviation also occurs in other batches.
What could be the problem that the internal reference is far (up to 0.6%) outside spec?
Regards
Roy Geverink