Hi Freddy, The ADS1261 inputs are high-impedance (~1 GOhm when PGA is enabled, and ~50 MOhms when PGA is bypassed), so when working with a signal generator that expects a 50-Ohm load you may see a doubling of the expected amplitude. It is important that these inputs are high-impedance so that when working with signals with larger output-impedances, that the ADS1261 does not load the signal source. You could add a 50-Ohm shunt resistor to the ADC inputs to make the input impedance appear to be a 50-Ohm load to your signal source, but I don't see why this would be necessary. You can always scale the conversion result by 1/2 in software and avoid the additional power dissipation that comes from the low-input impedance. FYI: There is an Excel Calculator for the ADS1261 (here: www.ti.com/.../ADS1261-EXCEL-CALC-TOOL) that you may want to reference to double check on the conversion from ADC codes to voltage.
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