The ADC incorporates offset and gain calibration commands, as well as user-offset and full-scale calibration registers to calibrate the ADC. The ADC1 calibration registers are 24-bits wide and the ADC2 calibration registers are 16-bits wide. Use calibration to correct internal ADC errors or overall system errors. Calibrate by sending calibration commands to the ADC, or by direct user calibration. In user calibration, the user calculates and writes the correction values to the calibration registers. The ADC performs self or system-offset calibration, or for full-scale calibration, system calibration. Perform offset calibration before full-scale calibration. After power-on, but before calibrating, wait for the power supplies and reference voltage to fully settle.