Abstract: In a power factor corrector including a PWM switch to switch a line current generated from a line voltage to charge a boost capacitor to thereby generate an output voltage, a piecewise on-time modulation apparatus and method comprise comparing a line voltage dependent voltage with an output voltage dependent voltage to generate a comparison signal to determine the on-time of the PWM switch. When the line voltage is lower than a threshold, the on-time of the PWM switch varies with the line voltage, and when the line voltage is higher than the threshold, the on-time of the PWM switch is constant.

Abstract: A two-phase driver comprises two H-bridge circuits each of them including a transformer and two switch assemblies connected to the opposite terminals of the primary side of the transformer, in which one of the switch assemblies is shared by the two H-bridge circuits. Each of the switch assemblies includes a high-side switch and a low-side switch, and each of the high-side switch and low-side switch is switched by a respective signal so as to modulate the loading currents supplied to two loading loops connected to the two H-bridge circuits, respectively.

Abstract: In a three-phase inverter configured driving circuit and method, three switch assemblies are connected in parallel between an input voltage and a reference voltage and switched to generate a three-phase AC voltage on the primary side of a three-phase transformer, so as to be transformed to a three-phase current from the secondary side of the transformer to provide for three loadings.

Abstract: In a power factor corrector including a PWM switch to switch a line current generated from a line voltage to charge a boost capacitor to thereby generate an output voltage, a piecewise on-time modulation apparatus and method comprise comparing a line voltage dependent voltage with an output voltage dependent voltage to generate a comparison signal to determine the on-time of the PWM switch. When the line voltage is lower than a threshold, the on-time of the PWM switch varies with the line voltage, and when the line voltage is higher than the threshold, the on-time of the PWM switch is constant.

Abstract: In a three-phase inverter configured driving circuit and method, three switch assemblies are connected in parallel between an input voltage and a reference voltage and switched to generate a three-phase AC voltage on the primary side of a three-phase transformer, so as to be transformed to a three-phase current from the secondary side of the transformer to provide for three loadings.

Abstract: A two-phase driver comprises two H-bridge circuits each of them including a transformer and two switch assemblies connected to the opposite terminals of the primary side of the transformer, in which one of the switch assemblies is shared by the two H-bridge circuits. Each of the switch assemblies includes a high-side switch and a low-side switch, and each of the high-side switch and low-side switch is switched by a respective signal so as to modulate the loading currents supplied to two loading loops connected to the two H-bridge circuits, respectively.

Abstract: A charge mode pulse-width modulation control method and apparatus includes setting up a detector at a primary side of a transformer to detect a current and feeding back the detected current to a current apparatus to provide a current output; an integrator providing charge output with a voltage mode, where the charges are supplied by the integrator which takes the output current of current source to implement mathematical integration, and produce an output voltage and providing the output voltage to a main controller as a reference for deciding whether or not to switch a switch. The control system can prevent the transformer from reaching magnetic saturation and the feedback control current signal from generating noises.