A gate voltage control/gate resistance changing circuit (21) is accommodated in the same package (P1) as a switching element (11), and outputs a driving signal to the switching element (11) to control turning on and off of the switching element (11). When an external signal is input from outside of the package (P1) to a terminal (3c) of the package (P1), a changing unit (221) accommodated in the package (P1) changes the switching speed of the switching element (11) based on the signal.

A method for operating a gate driver system includes measuring a first parameter according to a first priority schedule synchronously to a first edge of a switching signal generated by a gate driver integrated circuit and having a variable duty cycle. The method includes after measuring the first parameter of the gate driver system and prior to a second edge of the switching signal, measuring at least a second parameter of the gate driver system according to a first round-robin schedule synchronously to the first edge of the switching signal.

A drive circuit includes a second drive circuit that drives a semiconductor switching element in a case where a pulse width of a corresponding signal is determined to be larger than a second threshold, and a timing adjustment circuit that adjusts a timing at which the second drive circuit cooperates with a first drive circuit to drive the semiconductor switching element during a turn-off period of the semiconductor switching element due to drive of the first drive circuit.

A gate drive circuit that drives a power device by controlling charge and discharge of gate capacitance of the power device includes: a first semiconductor switch that charges the gate capacitance by being brought into conduction according to a first control signal; a second semiconductor switch that discharges the gate capacitance by being brought into conduction according to a second control signal; and a slew rate control circuit that is connected between a gate of the power device and a ground line, and controls a slew rate during discharge. The slew rate control circuit includes a capacitor and a third semiconductor switch connected in series. The third semiconductor switch is brought into conduction according to the second control signal.

A drive circuit includes a second drive circuit that drives a semiconductor switching element in a case where a pulse width of a corresponding signal is determined to be larger than a second threshold, and a timing adjustment circuit that adjusts a timing at which the second drive circuit cooperates with a first drive circuit to drive the semiconductor switching element during a turn-off period of the semiconductor switching element due to drive of the first drive circuit.

A semiconductor device includes a first switch and a first driver. The first switch selects and outputs one of a power supply potential and a generated potential as a first switch output potential based on a synchronization signal from a transmission circuit and a delayed signal delayed from the synchronization signal. The first driver charges a gate of a bipolar transistor element based on the synchronization signal of the transmission circuit and the first switch output potential.

A gate drive device for driving a switching element includes: a gate drive circuit that drives a gate of the switching element based on a gate drive signal and a drive performance adjustment signal; a gate voltage detection circuit that outputs an on detection signal or an off detection signal when detecting that a gate voltage of the switching element reaches an on determination set value or an off determination set value; and a control circuit that outputs the drive performance adjustment signal to the gate drive circuit to match a gate drive time with a predetermined gate drive time set value.

A turn-off circuit for a semiconductor switch includes an element having a variable resistance coupled to a control input of the semiconductor switch, a circuit for generating a control-input reference signal, and a control circuit coupled to adjust a resistance of the element having a variable resistance in response to the control-input reference signal in a closed control loop in order to turn off the semiconductor switch.

A circuit includes first to third transistors. The first transistor includes a first terminal coupled to a first voltage, and a second terminal coupled to a connection. The second transistor includes a gate terminal coupled to the gate terminal of the first transistor, a first terminal coupled to a second voltage, and a second terminal coupled to the connection. The third transistor includes a first terminal coupled to the connection, a second terminal coupled to a node between the second terminals of the first and second transistors. The third transistor is controlled to be turned ON at a beginning of a first edge of a driving signal on the connection to pull a voltage of the driving signal on the first edge toward a threshold voltage, and be turned OFF in response to and after the voltage of the driving signal on the first edge reaching the threshold voltage.

A power module apparatus includes a power substrate, at least one power device electrically connected to the power substrate and a gate-source board mounted relative to the power substrate, the gate-source board electrically connected to the at least one power device, a housing secured to the power substrate, and a clamping circuit electrically connected to the at least one power device. The clamping circuit being configured to reduce a voltage charge up at a gate of the at least one power device to within 8 V of a desired voltage.