Detecting failure for multi-rail supply protection

A method for detecting failure of a device, the method comprising:

• determining whether a first failure has occurred at the device based on a rate of change of a current at a high-side switching element of a power converter;
• determining whether a second failure has occurred at the device based on both a current at a low-side switching element of the power converter and a voltage at a switch node that is electrically coupled to the high-side switching element and the low-side switch;
• and
• electrically disconnecting the high-side switching element from a supply circuit in response determining that the first failure has occurred at the device or in response to determining that the second failure has occurred at the device.

A system comprising:

• a power converter configured to output an output voltage, the power converter comprising a high-side switching element and a low-side switching element, wherein a switch node is electrically coupled to the high-side switching element and the low-side switch;
• and
• a circuit for detecting failure of a device, the circuit comprising:
• an on-phase detector configured to determine whether a first failure has occurred at a device based on a rate of change of a current at the high-side switching element;
• an off-phase detector configured to determine whether a second failure has occurred at the device based on both a current at the low-side switching element and a voltage at the switch node;
• and
• protection switch circuitry configured to electrically disconnect the high-side switching element from a supply circuit in response to the on-phase detector determining that the first failure has occurred at the device or in response to the off-phase detector determining that the second failure has occurred at the device.