Abstract: A voltage control device and a switched capacitor system are provided. The voltage control device is applied to a switched capacitor circuit, the switched capacitor circuit includes multiple switch elements and multiple capacitors. The switch elements include at least a first switch element. The first switch element receives a gate-source voltage to control its conduction degree. The voltage control device performs a stage time-varying modulation or a continuous time-varying modulation on the gate-source voltage of the first switch element. During the period for the first switch element being turned-on, the gate-source voltage of the first switch element is modulated as multiple target voltages at multiple time points in response to a set of switch control signals. The voltage control device is disposed in the switched capacitor system.

Abstract: A forward converter includes a voltage conversion device, a switch and an auxiliary device. The voltage conversion device includes a primary winding and a secondary winding, and is configured to convert an input voltage into an output voltage. The switch is connected to the voltage conversion device, and is switched to make the voltage conversion device receive or not receive the input voltage. The auxiliary device is connected to the voltage conversion device. When the switch is cut off, the auxiliary device stores electrical energy released by the voltage conversion device and generates a compensation voltage, and when the switch is turned on, the auxiliary device provides the compensation voltage, wherein the compensation voltage and the input voltage have same polarity. The present disclosure further provides a forward power factor corrector including the forward converter described above and a rectifying device.

Abstract: A voltage converter is connected with a load. The voltage converter includes a power source, a first switching element, a second switching element, an energy storage inductor, an energy storage capacitor and N capacitor modules. The first switching element is connected between a first terminal of the power source and a first node. The second switching element is connected between the first node and a second node. A second terminal of the power source is connected with the second node. The energy storage inductor is connected between the first node and the third node. The N capacitor modules are connected between the third node and a fourth node, wherein N is a positive integer. The energy storage capacitor is connected between the fourth node and the second node.

Abstract: A spike suppression device, for suppressing a spike current in a switched capacitor circuit, and the switched capacitor circuit includes an output capacitor and at least one input capacitor. The spike suppression device includes an inductive reactance element and a switch unit. The inductive reactance element is disposed between the output capacitor and the at least one input capacitor. The switch unit is coupled to the inductive reactance element. The inductive reactance element generates an induced voltage in response to the spike current. The induced voltage is opposite to the spike current, and the switch unit forms a discharge path of the inductive reactance element.

Abstract: A forward converter includes a voltage conversion device, a switch and an auxiliary device. The voltage conversion device includes a primary winding and a secondary winding, and is configured to convert an input voltage into an output voltage. The switch is connected to the voltage conversion device, and is switched to make the voltage conversion device receive or not receive the input voltage. The auxiliary device is connected to the voltage conversion device. When the switch is cut off, the auxiliary device stores electrical energy released by the voltage conversion device and generates a compensation voltage, and when the switch is turned on, the auxiliary device provides the compensation voltage, wherein the compensation voltage and the input voltage have same polarity. The present disclosure further provides a forward power factor corrector including the forward converter described above and a rectifying device.

Abstract: A linear driving module includes: a control circuit, a dimming module, and a low-dropout regulator. The control circuit generates switch signals in response to a change in a pulsed DC voltage. The dimming module receives the pulsed DC voltage. The dimming module includes dimming units. Light-emitting diode units in the dimming units are in a light-on state or a light-off state. The low-dropout regulator receives an input voltage from the dimming unit, and converts the input voltage into a regulated voltage. The input voltage varies with the number of light-emitting diode units in the light-on state. The input voltage is lower than the pulsed DC voltage, and the regulated voltage is lower than the input voltage.

Abstract: A voltage converter is connected with a load. The voltage converter includes a power source, a first switching element, a second switching element, an energy storage inductor, an energy storage capacitor and N capacitor modules. The first switching element is connected between a first terminal of the power source and a first node. The second switching element is connected between the first node and a second node. A second terminal of the power source is connected with the second node. The energy storage inductor is connected between the first node and the third node. The N capacitor modules are connected between the third node and a fourth node, wherein N is a positive integer. The energy storage capacitor is connected between the fourth node and the second node.

Abstract: A linear driving module includes: a control circuit, a dimming module, and a low-dropout regulator. The control circuit generates switch signals in response to a change in a pulsed DC voltage. The dimming module receives the pulsed DC voltage. The dimming module includes dimming units. Light-emitting diode units in the dimming units are in a light-on state or a light-off state. The low-dropout regulator receives an input voltage from the dimming unit, and converts the input voltage into a regulated voltage. The input voltage varies with the number of light-emitting diode units in the light-on state. The input voltage is lower than the pulsed DC voltage, and the regulated voltage is lower than the input voltage.

Abstract: In driving a segmented LED loading, an alternating current (AC) voltage is rectified into a direct current (DC) voltage; the DC voltage is regulated into an input voltage and the input voltage is maintained higher than a lowest voltage used for lighting at least one LED segment of the segmented LED loading; the input voltage and a current flowing through the segmented LED loading is detected to generate a switch control signal and a current control signal; respective operation states of each of a plurality of switches of a LED segment switch module are controlled by the switch control signal to control each LED segment of the segmented LED loading as power-supply state or no-power-supply state; and the current of the segmented LED loading is regulated based on the current control signal.

Abstract: A dimming system comprises a controller and an AC-to-DC converter. The controller outputs a control signal in response to a dimming signal. The controller comprises a frequency adjustment circuit and a duty cycle adjustment circuit. The frequency adjustment circuit adjusts the frequency of the control signal in response to the dimming signal. The duty cycle adjustment circuit adjusts the duty cycle of the control signal in response to the dimming signal. The AC-to-DC converter converts an external power and to output a DC signal in response to the control signal so as to drive a light source by the DC signal. When the controller is operated at a first mode, the control signal has a first frequency and a first duty cycle. When the controller switches to a second mode, the control signal has a second frequency and a second duty cycle.

Abstract: A passive power factor correction circuit includes: a DC capacitor and an input capacitor, coupled to a rectifying circuit and charged by a DC voltage from the rectifying circuit; an output capacitor, coupled to a load; first diode and a second diode, coupled to the input capacitor and the output capacitor; and an inductor, coupled to the load, the input capacitor and the output capacitor. Charging into and discharging from the DC capacitor are completed within a half cycle of an input AC voltage.

Abstract: A dimming system comprises a controller and an AC-to-DC converter. The controller outputs a control signal in response to a dimming signal. The controller comprises a frequency adjustment circuit and a duty cycle adjustment circuit. The frequency adjustment circuit adjusts the frequency of the control signal in response to the dimming signal. The duty cycle adjustment circuit adjusts the duty cycle of the control signal in response to the dimming signal. The AC-to-DC converter converts an external power and to output a DC signal in response to the control signal so as to drive a light source by the DC signal. When the controller is operated at a first mode, the control signal has a first frequency and a first duty cycle. When the controller switches to a second mode, the control signal has a second frequency and a second duty cycle.

Abstract: A direct current (DC) conversion circuit suitable for driving a load comprises a buck-boost converter, a resonant stage circuit and an output stage circuit. The buck-boost converter has two input ends receiving a first DC signal, and two output ends outputting a second DC signal. The resonant stage circuit has two input ends receiving the second DC signal. The resonant stage circuit converts the second DC signal to energy and further converts the energy to a negative voltage by a resonance effect. The resonant stage circuit has two input ends outputting the energy. The output stage circuit has two input ends receiving the energy to store the energy, and two output ends outputting energy to the load.

Abstract: A DC conversion circuit in the disclosure includes a buck-boost converter and a resonant stage circuit. The buck-boost converter has two input ends, a negative output end and a positive output end. The buck-boost converter receives a first DC signal via its two input ends, and outputs a second DC signal via its two output ends. The resonant stage circuit has two input ends and two output ends. The resonant stage circuit receives the second DC signal via its two input ends, converts the second DC signal into energy for power charging, and outputs the energy to a load via its two output ends. Then, the resonant stage circuit converts the energy, which is used for power charging, to form a negative voltage by a resonance effect, and outputs the energy to the load via its two output ends.

Abstract: The present disclose relates to a power active buck power factor correction device, comprising: a AC source; a rectifying device coupled to the AC source for receiving and rectifying the AC source so as to generate an input voltage; a first converting device coupled to the assistance device for receiving, transmitting, converting and storing energy; a load coupled to the first converting device; and an assistance device coupled to the first converting device for generating an assistance voltage. Specifically, the polarity of the assistance voltage is same with the input voltage, but is contrary to an output voltage, so that the first converting device may continue to work and receive an input current under the input voltage is smaller than the output voltage while the discontinue time of the input current is getting shorter so as to obtain the perfected power factor correction effect.

Abstract: A power-saving method for a lamp power-saving system is provided. The method includes the following steps. A lamp control unit is provided to control a fluorescent lamp. The lamp control unit includes a power conversion circuit and a preheat and lighting circuit. The preheat and lighting circuit, coupled to the power conversion circuit and two terminals of the fluorescent lamp, preheats and activates the fluorescent lamp, and outputs a feedback signal indicating a current passing through the fluorescent lamp. When the feedback signal indicates the fluorescent lamp is in a preheat mode, a resonant circuit of the preheat and lighting circuit is enabled to preheat the fluorescent lamp via a current path provided by a diode bridge of the preheat and lighting circuit. When the feedback signal indicates the fluorescent lamp is lighted, the current path of the preheat and lighting circuit is disconnected to stop preheating.

Abstract: Systems and methods for lighting control are disclosed. The system may include at least one lighting device providing illumination and a handheld unit coupled with the lighting device to control at least one of a controllable lighting state, a controllable lighting intensity, and a controllable lighting effect of the lighting device. The handheld unit may include an image-capturing device and a processor coupled with the image-capturing device. The processor may be configured to control the image-capturing device to capture an image of a space affected by the lighting device; analyze an luminance level of the space; receive a lighting parameter; and provide a command to the lighting device for controlling at least one of the controllable lighting state, the controllable lighting intensity, and the controllable lighting effect of the lighting device based on at least one of the image, the luminance level, and the lighting parameter.

Abstract: The invention disclosed buck power factor correction system. The system includes: a first storing device, for storing and discharging energy; a first converter device, coupled to the first storing device, for transferring and converting energy; a second storing device, coupled to the first storing device, for storing and discharging energy; and a second converter device, coupled to the second storing device, for transferring and converting energy.

Abstract: A method for identifying a rated power of a HID lamp includes the steps of: outputting a first driving signal and a second driving signal to drive the HID lamp in order, and calculating a first electric characteristic variation of the HID lamp; and identifying the rated power of the HID lamp according to the first electric characteristic variation and a first default value.

Abstract: A light source driving device configured to drive a light-emitting unit is provided. The light source driving device includes a direct voltage source, a first capacitance unit, and a switching current adjustment circuit. The direct voltage source is coupled with the light-emitting unit and supplies a direct voltage. The first capacitance unit and the light-emitting unit are connected in parallel. The switching current adjustment circuit and the light-emitting unit are connected in series. The switching current adjustment circuit is configured to bear a part of a voltage stress of the direct voltage source and is configured to switch the direct voltage.