Abstract: A semiconductor device can include: a substrate having a semiconductor material; a plurality of semiconductor layers of a first conductivity type, and being sequentially stacked on the substrate, where a doping concentration of the semiconductor layers successively increases from bottom to top; a trench that extends from the surface of a topmost semiconductor layer into a bottommost semiconductor layer of the semiconductor layers; a plurality of field plates that correspond to the semiconductor layers, each field plate being located in a portion of the trench that corresponds to one of the semiconductor layers; and a trench pad located in a bottom and a sidewall of the trench, and being filled each space between two adjacent field plates, where the thickness of the trench pad between each field plate and corresponding semiconductor layer sequentially decreases from the bottom to the top.

Abstract: Disclosed is an ESD protection device, comprising: a semiconductor substrate; a semiconductor buried layer located in the semiconductor substrate; an epitaxial semiconductor layer located on the semiconductor substrate and comprising a first doped region and a second doped region, wherein the semiconductor substrate and the first doped region are of a first doping type, the semiconductor buried layer, the epitaxial semiconductor layer and the second doped region are of a second doping type, the first doping type and the second doping type are opposite to each other, and the first doped region forms a plurality of interfaces with the epitaxial semiconductor layer. The disclosure improves protection performance and maximum current bearing capacity without increasing parasitic capacitance of the ESD protection device.

Abstract: A load current adjusting circuit can include: a counter configured to generate first and second digital signals in accordance with a pulse signal, where a numerical relationship between the first and second digital signals is determined in accordance with a duty cycle of the pulse signal; and an adjusting circuit configured to adjust a load current to vary along with the duty cycle of the pulse signal in accordance with the first and second digital signals.

Abstract: An apparatus can include: a bleeder circuit coupled to a DC bus of an LED driving circuit having an SCR dimmer; the bleeder circuit being configured to stabilize a voltage of the DC bus at a predetermined value by drawing a bleed current through a bleed path in a first mode, and to cut off the bleed path in a second mode; and a controller configured to control the bleeder circuit to be in the first mode before the SCR dimmer is turned on, and to switch to the second mode after the SCR dimmer is turned on, where the predetermined value is greater than zero.

Abstract: A ripple suppression circuit for suppressing a ripple component in a drive current for an LED load includes: an output port connected to the LED load; a current filter circuit connected in series with the output port, and being configured to control the drive current based on an output voltage after a ripple component is filtered out, where the drive current is maintained as substantially stable; and a ripple shunt circuit connected between a drive current input terminal and a ground terminal, and being configured to shunt the drive current in response to the output voltage, where the output voltage is a voltage output from a power stage circuit that is coupled to the ripple suppression circuit.

Abstract: A multi-phase parallel converter can include: sampling circuits corresponding to power stage circuits to form a plurality of phases of the multi-phase parallel converter, where each sampling circuit samples an inductor current of a corresponding power stage circuit, and generates a sense signal; a current-sharing circuit that generates a current-sharing control signal according to a superimposed signal that is generated by adding the sense signal to a bias voltage signal; switching control circuits corresponding to the power stage circuits, where each switching control circuit receives the current-sharing control signal, and controls a switching operation of a corresponding power stage circuit; and a bias voltage generator that generates the bias voltage signal to gradually increase/decrease when a selected phase is to be disabled/enabled.

Abstract: In one embodiment, a control circuit configured to control a switch mode power supply, can include: (i) a compensation signal generating circuit configured to generate a compensation signal according to an error between an output voltage feedback signal and a first reference voltage of the switch mode power supply; (ii) a switching signal generating circuit configured to control a switching operation of a power switching device of the switch mode power supply according to the compensation signal; (iii) a judge circuit configured to determine an operation state of the switch mode power supply according to the output voltage feedback signal; and (iv) a loop gain regulating circuit configured to regulate a loop gain of the control circuit according to the operation state.

Abstract: A power supply including a bi-directional DC converter and a control method thereof are disclosed herein. The power supply includes first to third terminals, first and second semiconductor switches and a mode switching means. The first terminal is electrically coupled to an external power source. The second terminal is electrically coupled to a load. The third terminal is electrically coupled to a battery. The first and second semiconductor switches are electrically coupled in series between the first and second terminals. The mode switching means is electrically coupled to the first semiconductor switch, the second semiconductor switch and a bi-directional DC converter, respectively. The bi-directional DC converter is further electrically coupled to an intermediate node between the first semiconductor switch and the second semiconductor switch, and to the third terminal.

Abstract: An adaptive charge control circuit configured for a switching charger can include: an input voltage control circuit configured to receive an input voltage signal of the switching charger and an input voltage reference signal, and to generate a first error signal; an input current control circuit configured to receive an input current signal of the switching charger and an input current reference signal, and to generate a second error signal; a charging current control circuit configured to receive a charging current signal of the switching charger and a charging current reference signal, and to generate a third error signal; and a charging voltage control circuit configured to receive a charging voltage signal of the switching charger and a charging voltage reference signal, and to generate a fourth error signal.

Abstract: The present disclosure relates to a synchronous rectification circuit. Operation states of four transistor switches in the synchronous rectification circuit are adjusted in accordance with a detected input voltage signal of the synchronous rectification circuit to achieve synchronous rectification. Moreover, the transistor switches in a rectifier bridge and a switching control circuit are all integrated into a single chip to have an increased integration level, a reduced chip size, and high efficiency. The present disclosure also relates to a switching power supply comprising the above synchronous rectification circuit.

Abstract: A method of controlling a voltage switch circuit can include: controlling an output voltage of the voltage switch circuit to be switched from a first voltage input to a first switch circuit to a second voltage input to a second switch circuit to be no larger than a smaller one of the first and second voltages before the second switch circuit starts conducting; switching the output voltage to the second voltage when the second switch circuit starts conducting, where outputs of the first and second switch circuits are coupled together to provide the output voltage; and controlling the first switch circuit to turn off after the second switch circuit conducts and when the output voltage is no larger than the smaller one of the first and second voltages.

Abstract: A passive boost network configured to boost and output an AC power signal having a predetermined frequency, can include: an input port; an output port configured to provide the AC power signal; first and second passive components coupled in series between first and second terminals of the input port; a third passive component coupled in series with the second passive component between first and second terminals of the output port; and where the first passive component is one of a capacitor and an inductor, and the second and third passive components are each the other of the capacitor and the inductor.

Abstract: A control circuit for generating a switching control signal to control switching operations of a power switch in a power stage circuit, can include: a first control loop configured to receive a first voltage feedback signal, and to generate a first compensation signal; a voltage regulating circuit configured to receive an output voltage signal of the power stage circuit, and to generate a second compensation signal according to a difference between an output voltage signal of the power stage circuit during different time periods; and control and driving circuit configured to receive the first and second compensation signals and a sense voltage signal that represents a current through an inductor of the power stage circuit, and to generate an OFF signal, and a switching control signal according to the OFF signal and an ON signal.

Abstract: Disclosed are AC-DC voltage converter circuits and methods for low standby power consumption. In one embodiment, a method can include: (i) detecting operating states of an input power supply, where the input power supply is received by a safety capacitor and provided to a switching power supply circuit after being rectified and filtered; (ii) removing a phantom load when the input power supply operates in a normal operating state; (iii) loading the phantom load when the input power supply operates in an under voltage lock out state; and (iv) when the input power supply operates in the under voltage lock out state, using energy stored in the safety capacitor to supply power to a load of the switching power supply circuit and the phantom load, and disabling a power stage circuit until a voltage of the safety capacitor is reduced to less than a safety threshold value.

Abstract: A parameter identification circuit for a digital power converter having an inductor and a capacitor, can include: an inductor parameter circuit that receives an inductor current of the inductor, a capacitor voltage of the capacitor, a duty cycle in a start-up stage, and a predetermined inductor current, where the inductor parameter circuit obtains an inductor parameter according to an integrated value of the capacitor voltage, an integrated value of the duty cycle in the start-up stage, and the predetermined inductor current, when the inductor current rises to a level of the predetermined inductor current; and a capacitor parameter circuit that receives the inductor current, the capacitor voltage, and a predetermined capacitor voltage, where the capacitor parameter circuit obtains a capacitor parameter according to an integrated value of the inductor current and the predetermined capacitor voltage when the capacitor voltage rises to a level of the predetermined capacitor voltage.

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 multichannel constant current LED controlling circuit can include: (i) a control loop configured to generate a first control signal in accordance with a current feedback signal that represents a driving current flowing through an LED load, where the LED load comprises a plurality of LED strings coupled in series; (ii) a loop steady state network comprising a plurality of steady state holding components configured to hold a plurality of steady state control signals that correspond to a plurality of load states of the LED load, where when a state of the LED load varies, at least one of the steady state holding components is selected by the control loop to generate the first control signal; and (iii) a power switching transistor of a power stage circuit configured to generate a pseudo-constant output current to drive the LED load.

Abstract: A speaker driving apparatus can include: a sound pressure feedback unit configured to generate an electrical signal indicative of a sound pressure of a loudspeaker; a compensation unit configured to compensate an input audio signal according to the electrical signal indicative of the sound pressure of the loudspeaker to generate a compensated audio signal, where the sound pressure of the loudspeaker is linearly related to the input audio signal; and an amplification unit configured to amplify the compensated audio signal in order to drive the loudspeaker.

Abstract: A switching control circuit for controlling a multi-channel switching circuit can include: a logic control circuit that receives an external operation signal, and generates an enable signal, a trigger signal, and an order signal; a reference voltage regulation circuit that receives the enable signal, the trigger signal, the order signal, and a plurality of input voltage signals, and generates an adjustable reference voltage signal, where the reference voltage regulation circuit is also configured to select one of the plurality of input voltage signals based on the order signal; a feedback control circuit that receives the reference voltage signal, the plurality of input voltage signals, and the output voltage signal, and generates a feedback control signal; and a channel selection circuit that receives the order signal and the feedback control signal, and generates switching control signals to control switching operations of the multi-channel switching circuit.

Abstract: A converter can include: (i) a first switch having a first terminal for receiving an input voltage, and a second terminal coupled to a first terminal of a second switch; (ii) an inductor having a first terminal coupled to a common node of the first and second switches, and a second terminal coupled to a first terminal of a third switch, where second terminals of the second and third switches are coupled to ground; and (iii) a plurality of output channels coupled to a common node of the inductor and the third switch, where the converter operates in a buck-boost mode, a buck mode, or a boost mode based on the relationship between the input voltage and output voltages of the plurality of output channels.