Rise time for High Voltage input power rail to the Built-in Switching Regulator

Question: What is the min/max rise time for High Voltage input power rail to the Built-in Switching Regulator?

 

Answer:

The max rate of change of the High Voltage input power rail connecting SREGHVIN is 32 V/μS as the Absolute Maximum High Voltage Supply ramp time for the SREGHV pin is defined as 1μs. If the ramp rate for the input power supply (HV domain which powers the Built-in Switching Regulator) exceeds 32 V/μs, a 1Ω resistor in conjunction with the recommended 1 μF input capacitor is required for the input pin SREGHVIN.