Patent ID: 8503146

Claim:
A power supply system comprising: a switching device operable to be turned on and off for causing power to be delivered to a load, the switching device having a control terminal; driver circuitry coupled to the control terminal of the switching device, the driver circuitry operable to drive the switching device, the driver circuitry further operable to: detect a fault condition in the power supply system; if the switching device is turned on when the fault condition is detected, reduce the voltage at the control terminal of the switching device to a level just above the threshold voltage for the switching device; hold the voltage at the control terminal to the level just above the threshold voltage for a controlled duration, thereby reducing the saturation current flowing through the switching device; and further reduce the voltage down to a low voltage level near ground at the control terminal of the switching device after the controlled duration, thereby safely turning off the switching device; wherein the driver circuitry comprises a fault detection circuitry operable to detect the fault condition and a resistor-capacitor network coupled to the fault detection circuitry and to the switching device and operable if the fault condition is detected to control a rate of decrease of the voltage at the control terminal of the switching device from a high turn-on voltage level to the level just above the threshold voltage for the switching device.