The AMC1301 assumes normal operation as soon as VDD1, VDD2, and the input common-mode voltage (V_CM) are within the operational ranges, as specified in Electrical Characteristics table. In this mode, the output voltage is proportional to the input voltage.

The AMC1301 enters fail-safe mode whenever the high-side supply (VDD1) is missing or the input common-mode voltage (V_CM) exceeds the specified input-overvoltage detection level V_CMov. In this mode, the differential output voltage is a fixed, negative value (V_FAILSAFE). See the Analog Output section for details.