Abstract: A power factor correction circuit can include: a power meter configured to measure THD at an input port; a switching-type regulator that is controllable by a switching control signal in order to adjust a power factor of an input signal thereof; and a controller configured to generate the switching control signal to control the switching-type regulator to perform power factor correction, where the controller minimizes the THD by adjusting a current reference signal according to a measured THD, and the current reference signal represents an expected inductor current of the switching-type regulator.

Abstract: A power factor correction circuit can include: a power meter configured to measure THD at an input port; a switching-type regulator that is controllable by a switching control signal in order to adjust a power factor of an input signal thereof; and a controller configured to generate the switching control signal to control the switching-type regulator to perform power factor correction, where the controller minimizes the THD by adjusting a current reference signal according to a measured THD, and the current reference signal represents an expected inductor current of the switching-type regulator.

Abstract: A semiconductor device includes a type IV semiconductor base substrate, a first type III-V semiconductor layer formed over the base substrate, a second type III-V semiconductor layer formed over the first type III-V semiconductor layer. A two-dimensional charge carrier gas forms at an interface between the first and second type III-V semiconductor layers. First and second electrically conductive device terminals are in ohmic contact with the two-dimensional charge carrier gas. A gate electrode is formed on the first type III-V semiconductor layer and is configured to control a conduction state of the two-dimensional charge carrier gas. An electrically insulating region is disposed over the second type III-V semiconductor layer and is laterally between the gate electrode and the second electrically conductive device terminal. At least one diode is formed on the electrically insulating region and is electrically connected between the gate electrode and the second electrically conductive device terminal.

Abstract: A power factor correction circuit can include: a power meter configured to measure a power factor at an input port; a switching-type regulator that is controllable by a switching control signal in order to adjust the power factor of an input AC power; an EMI filter disposed between the switching-type regulator and the input port; and a controller configured to generate the switching control signal to maximize the power factor by adjusting a current reference signal according to a measured power factor, where the current reference signal represents an expected inductor current of the switching-type regulator.

Abstract: A power factor correction circuit can include: a power meter configured to measure THD at an input port; a switching-type regulator that is controllable by a switching control signal in order to adjust a power factor of an input signal thereof; and a controller configured to generate the switching control signal to control the switching-type regulator to perform power factor correction, where the controller minimizes the THD by adjusting a current reference signal according to a measured THD, and the current reference signal represents an expected inductor current of the switching-type regulator.

Abstract: Disclosed is a method and a device for detecting states of a battery and a battery pack. The disclosure obtains a first state of charge and a second state of charge of the battery by use of a charge calculation method and a method based on battery model, respectively. The charge calculation method is more accurate when the charge-discharge current is large and the method based on battery model performs better in handling a small current, so that a chemistry state of charge obtained by performing a weighted calculation for the first state of charge and the second state of charge can represent the real state of charge of the battery more precisely. The disclosure settles the difficulty on parameter extraction of the conventional model method, eliminates the influence of the accumulated error of the charge calculation method, and combines the advantages of the method based on the battery model and the coulometer method.

Abstract: In one embodiment an LED driving circuit can include: (i) a rectifier circuit configured to receive an AC input power supply through a TRIAC, and to generate a bus voltage; (ii) a driving current generator configured to convert the bus voltage to a constant driving current and an output voltage to drive an LED load; and (iii) a current distribution circuit coupled between a positive pole and a negative pole of the bus voltage, where the current distribution circuit is configured to sample an input current to generate a sense signal, and to compare the sense signal against a voltage reference signal that represents an expected input current, so as to regulate the input current according to the voltage reference signal.

Abstract: In one embodiment an LED driving circuit can include: (i) a rectifier circuit configured to receive an AC input power supply through a TRIAC, and to generate a bus voltage; (ii) a driving current generator configured to convert the bus voltage to a constant driving current and an output voltage to drive an LED load; and (iii) a current distribution circuit coupled between a positive pole and a negative pole of the bus voltage, where the current distribution circuit is configured to sample an input current to generate a sense signal, and to compare the sense signal against a voltage reference signal that represents an expected input current, so as to regulate the input current according to the voltage reference signal.