Hi Burak, A couple of things schematically. You need to have a 330nF cap connected between AVDD and AVSS. Also, if you use large resistances in the input path the 22uF caps will take a significant amount of time to settle to 1/2 LSB, so you might want to consider this moving forward. As your maximum input voltage is +/- 2.048V (based on external reference input) then you can safely use the PGA enabled at a gain of 1 with the single-ended measurements. The external reference input can have a range that is within the range of the supply. This information is in section 7.3 of the ADS124S06 datasheet on page 8. So you can connect REFN0 to ISOGND or AVSS. If you connect to AVSS then you should disable the negative reference buffer. Connecting to ISOGND probably makes the most sense and you can enable both the positive and negative reference buffers. For the calibration, each input channel should be calibrated using SYGCAL. Before issuing SYGCAL, issue the SFOCAL first. Following the SYGCAL, store the settings in your micro or some other flash to be able to restore them when changing channels. After the SYGCAL the new gain calibration values will be in the three FSCAL registers. Store these settings, and move to the next input repeating the process. When muxing through the channels, restore the FSCAL registers for that channel before starting the conversion. Best regards, Bob B
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