Abstract: A driving device for driving a light-emitting element includes a bridge rectifier, a first capacitor, an inductive control circuit, a transformer, a power switch element, an output stage circuit, and a controller. The bridge rectifier generates a rectified voltage. The inductive control circuit includes an inductor, and adjusts an inductive current through the inductor according to the rectified voltage and a first control voltage. The first control voltage is selectively used to perform a PFM (Pulse Frequency Modulation) operation. The transformer generates a transformation voltage according to the inductive voltage of the inductor. The output stage circuit generates an output voltage according to the transformation voltage. The light-emitting element determines whether to generate light according to the output voltage. The controller detects the rectified voltage, and determines the first control voltage according to the rectified voltage.

Abstract: A power supply circuit includes a transformer, a PWM IC, an input voltage detecting circuit, a detecting voltage adjusting circuit, and a driving voltage supply circuit. The transformer is configured to receive an input voltage on a primary side and provide an output voltage on a secondary side. The PWM IC is configured to activate the driving voltage according to a first detecting voltage and a second detecting voltage. The input voltage detecting circuit is disposed on the primary side of the transformer and configured to provide a first voltage and a second voltage associated with the input voltage. The detecting voltage adjusting circuit is disposed on the primary side of the transformer and configured to provide the first and the second detecting voltages according to the first and the second voltage. The driving voltage supply circuit is configured to provide the driving voltage for operating the PWM IC.

Abstract: A voltage compensation driving circuit is provided. The voltage compensation driving circuit converts input power into output power and auxiliary power. The voltage compensation driving circuit provides a boost control signal according to an output current of the output power, and the boost control signal has a duty cycle corresponding to the output current. The voltage compensation driving circuit boosts the auxiliary power by the boost control signal to generate a compensation voltage and transmits the compensation voltage to a light emitting device string via a boost resistor, so as to linearly control a brightness of the light emitting device string.

Abstract: A power conversion device is provided. The power conversion device includes a main transformer circuit, a power switch, an auxiliary transformer, a resonant circuit, and a switch circuit. When the power switch is turned on, the switch circuit is enabled according to energy stored in an output capacitor of the main transformer circuit, so that energy associated with a secondary side of a main transformer is coupled to the resonant circuit via the auxiliary transformer so the resonant circuit obtains coupling energy. When the power switch is turned off, the resonant circuit and a parasitic capacitor of the power switch form a resonant tank coupled to a grounding terminal of a power supply side based on the coupling energy.

Abstract: A light-emitting diode (LED) driving circuit may include: a power supply circuit, arranged to provide power to a first set of LEDs and a second set of LEDs; a first linear current regulator and a second linear current regulator, where any linear current regulator of the linear current regulators and a corresponding set of LEDs within the sets of LEDs are coupled to each other in series and coupled between a power terminal and a ground terminal of the power supply circuit; and a control circuit, coupled to the linear current regulators, arranged to control the linear current regulators to drive the sets of LEDs, respectively, to make currents respectively passing through the sets of LEDs be substantially equal to each other. Aforementioned any linear current regulator may include a comparator, a power switch, and a resistor, and the control circuit may include a detection circuit and parameter control circuits.

Abstract: A light-emitting diode (LED) driving circuit may include: a power supply circuit, arranged to provide power to a first set of LEDs and a second set of LEDs; a first linear current regulator and a second linear current regulator, where any linear current regulator of the linear current regulators and a corresponding set of LEDs within the sets of LEDs are coupled to each other in series and coupled between a power terminal and a ground terminal of the power supply circuit; and a control circuit, coupled to the linear current regulators, arranged to control the linear current regulators to drive the sets of LEDs, respectively, to make currents respectively passing through the sets of LEDs be substantially equal to each other. Aforementioned any linear current regulator may include a comparator, a power switch, and a resistor, and the control circuit may include a detection circuit and parameter control circuits.

Abstract: A recharger includes a power supply circuit, an output circuit, a detection circuit, a micro-controller, and a restart circuit. The detection circuit includes a resistor and an NTC thermistor. The resistor includes a first end coupled to an auxiliary voltage provided by the power supply circuit. The NTC thermistor includes a first end coupled to a second end of the resistor and a second end coupled to a bias voltage. The micro-controller, including a pin coupled between the resistor and the NTC thermistor, turns off when the pin level is lower than a reference voltage. The restart circuit includes a comparator having a positive input end coupled to the pin, a negative input end coupled to a restart voltage, and an output arranged to output an enable signal when the level of the pin is higher than the restart voltage, thereby activating the output circuit for providing an output voltage.

Abstract: A power supply device includes an input stage circuit, a controller, a multi-order resonant circuit, a transformer, and an output stage circuit. The input stage circuit generates a switching voltage according to an input voltage. The controller generates a first control voltage and a second control voltage according to the switching voltage. The multi-order resonant circuit provides a reference voltage at a first node. The multi-order resonant circuit includes a first current path and a second current path. The first node is respectively coupled through the first current path and the second current path to a ground voltage. The first current path and the second current path are selectively closed or open according to the first control voltage and the second control voltage. The output stage circuit generates an output voltage according to the transformation voltage of the transformer.

Abstract: A power supply circuit includes a transformer, two load-monitoring circuits, a pulse-width modulation integrated circuit, and a burst mode control circuit. The first load-monitoring circuit is disposed on the primary side of the transformer for detecting a first current flowing through the primary side, thereby providing a corresponding first detecting voltage. The first load-monitoring circuit is configured to conduct or cut off the first current according to a control signal. The pulse-width modulation integrated circuit is configured to provide the control signal according to the first detecting voltage. The second load-monitoring circuit is disposed on the secondary side of the transformer for detecting a second current flowing through the secondary side, thereby providing a corresponding second detecting voltage. The burst mode control circuit is configured to adjust the value of the first detecting voltage according to the second detecting voltage.

Abstract: A voltage compensation driving circuit is provided. The voltage compensation driving circuit converts input power into output power and auxiliary power. The voltage compensation driving circuit provides a boost control signal according to an output current of the output power, and the boost control signal has a duty cycle corresponding to the output current. The voltage compensation driving circuit boosts the auxiliary power by the boost control signal to generate a compensation voltage and transmits the compensation voltage to a light emitting device string via a boost resistor, so as to linearly control a brightness of the light emitting device string.

Abstract: A power conversion device is provided for supplying power to an electronic device. The power conversion device includes a power supply connector, a voltage conversion circuit, a switch circuit and a detection circuit. The power supply connector is configured to couple with the electronic device. The voltage conversion circuit is configured to provide a suitable voltage level for the electronic device. The switch circuit is coupled between the voltage conversion circuit and the power supply connector. When the power supply connector is coupled with the electronic device and a ground pin of the power supply connector is fully shielded, the detection circuit configures the switch circuit to be conducted for supplying power to the electronic device.

Abstract: A power supply circuit includes: an alternating current-to-direct current (AC-to-DC) converter, a transformer, a first current switch, a switch control circuit and a power factor enhancement circuit. The AC-to-DC converter converts an AC power signal into a DC power signal. The transformer includes a primary side and a secondary side, where a first terminal of the primary side is coupled to the AC-to-DC converter, a second terminal of the secondary side is coupled to a ground voltage level, a first terminal of the first current switch is coupled to a second terminal of the primary side, and a second terminal of the first current switch is coupled to the ground voltage level through an impedance component. The power factor enhancement circuit selectively adjusts a zero current detection voltage to make the switch control circuit set the first current switch to be in a conducting state.

Abstract: A recharger includes a power supply circuit, an output circuit, a detection circuit, a micro-controller, and a restart circuit. The detection circuit includes a resistor and an NTC thermistor. The resistor includes a first end coupled to an auxiliary voltage provided by the power supply circuit. The NTC thermistor includes a first end coupled to a second end of the resistor and a second end coupled to a bias voltage. The micro-controller, including a pin coupled between the resistor and the NTC thermistor, turns off when the pin level is lower than a reference voltage. The restart circuit includes a comparator having a positive input end coupled to the pin, a negative input end coupled to a restart voltage, and an output arranged to output an enable signal when the level of the pin is higher than the restart voltage, thereby activating the output circuit for providing an output voltage.