Hi,
I’m working with the AD7357 and I’d like to confirm the relationship between the Full-Scale Error specified in the datasheet and the accuracy of the internal voltage reference.
The datasheet specifies the internal reference voltage as 2.048 V with a typical error of ±5 mV, which corresponds to approximately ±0.244%. At the same time, the Positive Full-Scale Error is specified as ±20 LSBs, and since 8192 LSBs represent half-scale on this 14-bit ADC, 20/8192 also results in ~0.244%, suggesting a direct correlation.
So my questions are:
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Is the Positive Full-Scale Error in the AD7357 datasheet primarily due to the tolerance of the internal voltage reference?
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If I use an external voltage reference with higher accuracy (e.g., 0.02%), can I expect a proportionally lower Full-Scale Error on the ADC output? Or are there other dominant contributors (e.g., internal gain error, linearity)?
I appreciate any clarification on this. Thank you!
Best regards,
Fabio Pavanati
