To minimize input leakage of the measurement channel, tie the unused input channels to mid-supply (VAVDD + VAVSS) / 2. Use the 2.5-V reference output voltage for this purpose if operating with single 5-V supply. Do not float unused digital inputs. Tie all unused digital inputs to the appropriate levels, VDVDD or VDGND, including when in power-down mode. Do not float (3-state) the digital inputs to the ADC or excessive power-supply leakage current can result. If the DRDY output is unused, leave the pin unconnected or connect to an external circuit.