If you need a dedicated ADC, it might just be a good idea to put an ATMega328P on your board. The example code is provided, and we are wondering whether there are methodology errors.

Operating on voltages from 4V to 12V, both devices are specified for operation from -40°C to 125°C. The OPA725 comes in SOT23-5 and SO-8 packages and the OPA2726 is available in an MSOP-10.

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