A method and an apparatus for driving a power switch tube. The apparatus includes an input unit, a drive unit, a transformer and a power switch tube. The input unit is connected to the drive unit, which is configured to input a group of drive signals, and the group of drive signals includes four drive signals, where the first drive signal and the second are complementary signals, and a dead time exists; the third drive signal and the fourth are complementary signals, and a dead time exists; the phase difference between the first drive signal and the third is 180 degrees, and the phase difference between the second drive signal and the fourth is 180 degrees; the drive unit is configured to power on a field winding of the transformer; and the transformer provides a drive voltage signal for the power switch tube.

A switching power conversion apparatus includes: a multi-level power stage, a PWM control circuit, a multi-level driver circuit, a bootstrap capacitor control circuit and a driving power control circuit. The bootstrap capacitor control circuit includes bootstrap capacitor control switches. During a charging period, a bootstrap control signal controls the bootstrap capacitor control switches, to electrically connect a second bootstrap node to the ground voltage level, whereby the supply voltage charges the bootstrap capacitor via the bootstrap diode. During a pumping period, the bootstrap control signal controls the bootstrap capacitor control switches to electrically connect the second bootstrap node to one of the upper-gate nodes or the switching node, whereby the voltage of the first bootstrap node is pumped to a corresponding pumping voltage level.

A switching power conversion apparatus includes: a multi-level power stage, a PWM control circuit, a multi-level driver circuit, a bootstrap capacitor control circuit and a driving power control circuit. The bootstrap capacitor control circuit includes bootstrap capacitor control switches. During a charging period, a bootstrap control signal controls the bootstrap capacitor control switches, to electrically connect a second bootstrap node to the ground voltage level, whereby the supply voltage charges the bootstrap capacitor via the bootstrap diode. During a pumping period, the bootstrap control signal controls the bootstrap capacitor control switches to electrically connect the second bootstrap node to one of the upper-gate nodes or the switching node, whereby the voltage of the first bootstrap node is pumped to a corresponding pumping voltage level.

A switching power conversion apparatus includes: a multi-level power stage, a PWM control circuit, a multi-level driver circuit, a bootstrap capacitor control circuit and a driving power control circuit. The bootstrap capacitor control circuit includes bootstrap capacitor control switches. During a charging period, a bootstrap control signal controls the bootstrap capacitor control switches, to electrically connect a second bootstrap node to the ground voltage level, whereby the supply voltage charges the bootstrap capacitor via the bootstrap diode. During a pumping period, the bootstrap control signal controls the bootstrap capacitor control switches to electrically connect the second bootstrap node to one of the upper-gate nodes or the switching node, whereby the voltage of the first bootstrap node is pumped to a corresponding pumping voltage level.

A switching power conversion apparatus includes: a multi-level power stage, a PWM control circuit, a multi-level driver circuit, a bootstrap capacitor control circuit and a driving power control circuit. The bootstrap capacitor control circuit includes bootstrap capacitor control switches. During a charging period, a bootstrap control signal controls the bootstrap capacitor control switches, to electrically connect a second bootstrap node to the ground voltage level, whereby the supply voltage charges the bootstrap capacitor via the bootstrap diode. During a pumping period, the bootstrap control signal controls the bootstrap capacitor control switches to electrically connect the second bootstrap node to one of the upper-gate nodes or the switching node, whereby the voltage of the first bootstrap node is pumped to a corresponding pumping voltage level.

A circuit for decoding a pulse width modulated (PWM) signal generates an output signal switching between a first and second logic values as a function of a duty-cycle of the PWM signal. Current generating circuitry receives the PWM signal and injects a current to and sinks a current from an intermediate node as a function of the values of the PWM signal. A capacitor coupled to the intermediate node is alternatively charged and discharged by the injected and sunk currents, respectively, to generate a voltage. A comparator circuit coupled to the intermediate node compares the generated voltage to a comparison voltage and drives the logic values of the output signal as a function of the comparison.

A circuit for decoding a pulse width modulated (PWM) signal generates an output signal switching between a first and second logic values as a function of a duty-cycle of the PWM signal. Current generating circuitry receives the PWM signal and injects a current to and sinks a current from an intermediate node as a function of the values of the PWM signal. A capacitor coupled to the intermediate node is alternatively charged and discharged by the injected and sunk currents, respectively, to generate a voltage. A comparator circuit coupled to the intermediate node compares the generated voltage to a comparison voltage and drives the logic values of the output signal as a function of the comparison.

A power electronics device has a first power semiconductor switch and a driver circuit and enables a supply of electrical voltage to a driver circuit. An auxiliary circuit arrangement has a supply capacitor, an auxiliary capacitor, a normally off auxiliary semiconductor switch, a diode and a bootstrap diode. The auxiliary semiconductor switch is connected to a reference potential connection of the first power semiconductor switch via a connection point, starting from the connection point, a series connection of the diode, a second connection point and the auxiliary capacitor is arranged in parallel with the auxiliary semiconductor switch. When the auxiliary semiconductor switch is in the off state, the auxiliary capacitor is charged by the flow of current through the first power semiconductor switch.

The present invention provides a control circuit and a control method for a switch circuit and a switching-mode power supply circuit. The control method comprises following steps: detecting an output voltage or an output current, and adjusting an upper limit value and a lower limit value of an inductor current according to a result of comparing the output voltage or the output current with the corresponding reference; and sampling the inductor current, and controlling a main switch transistor in the circuit to be switched off when a sampling current rises to the upper limit value, and controlling the main switch transistor to be switched on when the sampling current drops to the lower limit value. In the present invention, the inductor current is fast in response without overshoot, the output voltage drops very little, there is no overshoot in a process of voltage recovery, and circuit transient response is fast.

The present invention provides a control circuit and a control method for a switch circuit and a switching-mode power supply circuit. The control method comprises following steps: detecting an output voltage or an output current, and adjusting an upper limit value and a lower limit value of an inductor current according to a result of comparing the output voltage or the output current with the corresponding reference; and sampling the inductor current, and controlling a main switch transistor in the circuit to be switched off when a sampling current rises to the upper limit value, and controlling the main switch transistor to be switched on when the sampling current drops to the lower limit value. In the present invention, the inductor current is fast in response without overshoot, the output voltage drops very little, there is no overshoot in a process of voltage recovery, and circuit transient response is fast.