Patent ID: 8598921
Filing Date: 2013-12-03
Classification: H03K

Abstract:
1. A driving circuit for driving a power semiconductor switch, comprising a signal-processing unit for generating a gate signal for a gate of the power semiconductor switch, the driving circuit including a resistor series circuit which is connectable to a power terminal, used for the current supply, of the power semiconductor switch, and whose output is connected to a first input of the signal-processing unit, and the signal-processing unit having a second input for a reference voltage for the collector-emitter voltage of the power semiconductor switch, wherein at least one semiconductor device is provided which is implemented in such a way that it is operated in breakdown in response to the exceedance of a specific collector-emitter voltage of the power semiconductor switch, an output of the at least one semiconductor device being connected via a conductive interconnect to a terminal between the resistors of the resistor series circuit or to the resistor-series-circuit output which is connected to the signal-processing unit, and the breakdown voltage of the at least one semiconductor device being selected in such a way that the potential at the output of the at least one semiconductor device is greater than the potential at the gate of the power semiconductor switch in the ON state of the power semiconductor switch, wherein a further semiconductor device is provided which is connected in series to the at least one first semiconductor device, a switch being positioned parallel to this further semiconductor device and its gate being connected indirectly or directly to an output of the signal-processing unit, to which output, in particular, the gate of the power semiconductor switch is connectable, the driving circuit being implemented in such a way that the signal-processing unit closes the switch in the ON state of the power semiconductor switch and/or at the beginning of the circuit-breaking operation of the power semiconductor switch.