Hi Yoshikazu-san, are the results mentioned in the Excel sheet with global-chop mode enabled or disabled? With global-chop mode disabled the ~200uV offset for the current shunt measurement would be within the expected specification. For the voltage measurement, the 0.75mV offset look to large. What data rate (or OSR) are they using? Could they provide the raw conversion results from the ADC for the measurements with 0A current and 0V voltage? Could you ask the customer to measure the offset with the inputs internally shorted by setting MUX0[1:0] = 01b and MUX1[1:0] = 01b? And do the measurement both with global-chop mode enabled and disabled. That way we can potentially identify if the offset is coming from the device itself or rather the external circuitry. Note that ADC1 offers better offset performance than ADC0. Therefore it would be preferable to use ADC1 for the current shunt measurement. I wanted to mention that we also offer ADS131B02-Q1. This device has improved offset performance compared to ADS131M02-Q1 and also integrates an oscillator so that an external clock would not be required. The ADS131M02-Q1 and ADS131B02-Q1 are pin-to-pin compatible. Regards, Joachim Wuerker
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