The device input circuitry accurately measures signals on common-mode voltages beyond the power-supply voltage, V_S. For example, the voltage applied to the V_S power-supply pin can be 5 V, whereas the load power-supply voltage being monitored (V_CM) can be as high as 36 V. At power-up, for applications where the common-mode voltage (V_CM) slew rate is greater than 6 V/μs with a final common-mode voltage greater than 20 V, the V_S supply is recommended to be present before V_CM. If the use case requires V_CM to be present before V_S with V_CM under these same slewing conditions, then a 331-Ω resistor must be added between the V_S supply and the VS pin bypass capacitor.

Power-supply bypass capacitors are required for stability, and must be placed as close as possible to the supply and ground pins of the device. A typical value for this supply bypass capacitor is 0.1 µF. Applications with noisy or high-impedance power supplies may require additional decoupling capacitors to reject power-supply noise.

During slow power-up events, current flow through the sense resistor or voltage applied to the REF pin can result in the output voltage momentarily exceeding the voltage at the LIMITx pins, resulting in an erroneous indication of an out-of-range event on the ALERTx output. When powering the device with a slow ramping power rail where an input signal is already present, all alert indications should be disregarded until the supply voltage has reached the final value.