Abstract: The invention relates to a method for determining the switching state of a transistor having an insulated drive electrode. The drive electrode is charged during a switch-on cycle depending on a drive signal and is discharged during a switch-off cycle depending on the drive signal. The transistor turns on or turns off depending on the charge stored on the drive electrode. The temporal profile of a charging and discharging current of the drive electrode or the temporal profile of the charge stored on the drive electrode is evaluated in order to determine the switching state. A state signal dependent on the switching state is provided, as is an apparatus for carrying out this method.

Abstract: A DC-DC converter is provided with a series circuit formed by an inductor and a capacitor, an output voltage for a load being tapped off across the capacitor and the load bringing about a load current. The converter also has a changeover switch for connecting an input voltage to the series circuit or for short-circuiting the series circuit and a control circuit for controlling the changeover switch in such a way that the changeover switch alternately short-circuits the series circuit or connects it to the input voltage. The converter also has a means for increasing a resistance in series with the series circuit at least in the event of the series circuit being short-circuited by means of the changeover switch, if the load current falls by a specific value.

Abstract: A half-bridge circuit includes: a vertically designed n-conducting first MOS transistor that is integrated in a first semiconductor body having a front side and a rear side; and a vertically designed p-conducting second MOS transistor that is integrated in a second semiconductor body having a front side and a rear side. The first and second transistors are connected in series between a first connection terminal and a second connection terminal. The half-bridge circuit also includes a drive circuit for driving the first and second transistors. The first and second transistors are applied to a common connection plate.

Abstract: A half-bridge circuit includes: a vertically designed n-conducting first MOS transistor that is integrated in a first semiconductor body having a front side and a rear side; and a vertically designed p-conducting second MOS transistor that is integrated in a second semiconductor body having a front side and a rear side. The first and second transistors are connected in series between a first connection terminal and a second connection terminal. The half-bridge circuit also includes a drive circuit for driving the first and second transistors. The first and second transistors are applied to a common connection plate.