Method and device for actuating a power circuit breaker

A device for driving a semiconductor power switch connected between two energy storage devices in a wiring system of a vehicle equipped with an integrated starter generator, comprising:

• a semiconductor power switch having a switching path, and a control input for controlling said power switch with a control voltage Vst as a transfer gate to a non-conductive off-state or to a conductive on-state;
• said power switch having two transistors or groups of transistors connected in series, wherein, in an off-state of said power switch, at least one of said two transistors or groups of transistors is blocked;
• at least one diode assigned to each transistor or group of transistors for recording a chip temperature;
• a charge pump for generating the control voltage, said charge pump driving said transistors of said power switch, in the conductive on-state, in each case only to such an extent that the chip temperature of each transistor of said power switch is maintained at a predetermined setpoint temperature;
• and
• a temperature recording unit configured to compare the chip temperature with the predetermined setpoint temperature and to output an enable signal representing a result of the comparison to said charge pump, and wherein a resistance of said switching path is increased when the setpoint temperature is reached.