Hi Falk, welcome to our e2e forum and thanks a lot for your interest in ADS1220 . I am sorry that the information provided in the datasheet is not 100% clear. In your case you will only leverage half of the available code range of the ADC, because you are only measuring 'differentially positive' signals. I personally don't like to call this losing 1 bit of resolution, because the input referred noise is still the same as if you were to measure a signal that would utilize both the positive and negative code range. For AIN0 = AVSS the ADS1220 will output codes which are equivalent to a differential input voltage of VIN = 0V, means values close to 000000h as shown in Table 13 in the datasheet. For AIN0 = AVDD the ADS1220 will output codes which are equivalent to a differential input voltage of VIN = 5V, means values close to 7FFFFFh. Let me know if this answers your question. Regards,
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