Abstract: A power factor correction circuit for a boost converter comprises a voltage converting means and a voltage-to-time converting means. The voltage converting means converts a supply voltage based on a time period of a turn-on duration Ton and a turn-off duration Toff of the boost converter into an output voltage. The voltage-to-time converting means generates the turn-on duration Ton based on the output voltage from the voltage converting means. The power factor correction circuit adjusts the turn-on duration Ton substantially in accordance with the following relationship: T on = T T on + T off ? first ? parameter second ? parameter The first parameter includes at least one first process-dependent parameter and the second parameter includes at least one second process-dependent parameter.

Abstract: A soft-switching power converter includes a main switch, an energy-releasing switch, and an inductive coupled unit. The main switch is a controllable switch. The energy-releasing switch is coupled to the main switch. The inductive coupled unit is coupled to the main switch and the energy-releasing switch. The inductive coupled unit includes a first inductance, a second inductance coupled to the first inductance, and an auxiliary switch unit. The auxiliary switch unit is coupled to the second inductance to form a closed loop. The main switch and the energy-releasing switch are alternately turned on and turned off. The auxiliary switch unit is controlled to start turning on before the main switch is turned on so as to provide at least one current path.

Abstract: The present invention relates to a pitch-variable battery fixture and a battery cell formation apparatus having the same. A pitch of clamping plates of a plurality of clamping blocks is increased by a slide actuator of the pitch-variable battery fixture, and then the clamping plates are inserted into a plurality of compartments of a battery tray. The clamping plates are urged to clamp batteries by the slide actuator. The battery tray is provided for placement of the batteries, and a compressing force is exerted for shaping the batteries during a battery cell formation. The pitch-variable battery fixture is provided for clamping batteries having different thicknesses. According to the actual thickness of each battery, the thickness of the formed battery can be shaped.

Abstract: A power supply system with current sharing includes a current sharing bus, a plurality of power supply units, and a plurality of controllers. The power supply units are connected to each other through the current sharing bus. Each power supply unit provides a current sharing signal value to the current sharing bus, and provides an output current to a load. Each controller receives current sharing signal values provided from other power supply units and current signal values corresponding to the output currents. When determining that the current signal value is less than a reference current sharing signal value, the controller increases an output voltage of the power supply unit to increase the output current. Otherwise, the controller decreases the output voltage to decrease the output current so that so that the output currents of the power supply units are shared to supply power to the load.

Abstract: A control circuit is configured to control a flyback circuit comprising a primary-side switch, a secondary-side rectifier and a transformer. The control circuit comprises a feedback control circuit configured to generate a secondary-side control signal based on a current ripple signal of the transformer, and at least one of a direct-current component of an output voltage signal and a direct-current component of an output current signal of a secondary side of the flyback circuit, wherein the secondary-side control signal is configured to control a turn-off of the secondary-side rectifier, an isolated transmission circuit coupled to the feedback control circuit and configured to generate a first primary-side control signal based on the secondary-side control signal, and a primary control circuit coupled to the isolated transmission circuit and configured to control a turn-on of the primary-side switch in response to receiving the first primary-side control signal.

Abstract: A control circuit is configured to control a flyback circuit comprising a primary-side switch, a secondary-side rectifier and a transformer. The control circuit comprises a feedback control circuit configured to generate a secondary-side control signal based on a current ripple signal of the transformer, and at least one of a direct-current component of an output voltage signal and a direct-current component of an output current signal of a secondary side of the flyback circuit, wherein the secondary-side control signal is configured to control a turn-off of the secondary-side rectifier, an isolated transmission circuit coupled to the feedback control circuit and configured to generate a first primary-side control signal based on the secondary-side control signal, and a primary control circuit coupled to the isolated transmission circuit and configured to control a turn-on of the primary-side switch in response to receiving the first primary-side control signal.

Abstract: In one embodiment, a power supply controller, or alternately a semiconductor device having a power supply controller, may have a first circuit configured to form a sense signal that is representative of a signal from an auxiliary winding of a transformer. A feedback circuit may be configured to allow the sense signal to increase in response to a turn-off of the power switch, to subsequently detect a second increase of the sense signal prior to subsequently turning on the power switch, and to form a feedback signal as a value of the sense signal responsively to the second increase of the sense signal.

Abstract: A switched-mode power supply with near valley switching includes a quasi-resonant converter. The converter includes a switch element that is turned on not only at the valley, but also in a window range of ?tNVW close to the valley, where the voltage across the switch element is at its minimum. This advantageously reduces switching loss and maintains a balance between efficiency and frequency variation.

Abstract: In one embodiment, a power supply controller, or alternately a semiconductor device having a power supply controller, may have a first circuit configured to form a sense signal that is representative of a signal from an auxiliary winding of a transformer. A feedback circuit may be configured to allow the sense signal to increase in response to a turn-off of the power switch, to subsequently detect a second increase of the sense signal prior to subsequently turning on the power switch, and to form a feedback signal as a value of the sense signal responsively to the second increase of the sense signal.

Abstract: In one embodiment, a power supply controller, or alternately a semiconductor device having a power supply controller, may have a first circuit configured to form a sense signal that is representative of a signal from an auxiliary winding of a transformer. A feedback circuit may be configured to allow the sense signal to increase in response to a turn-off of the power switch, to subsequently detect a second increase of the sense signal prior to subsequently turning on the power switch, and to form a feedback signal as a value of the sense signal responsively to the second increase of the sense signal.

Abstract: A power adapter includes a protocol integrated circuit (IC) on a secondary side of a transformer and a controller IC on a primary side of the transformer. The power adapter has an output voltage that changes depending on the charging voltage requirement of an electronic device (e.g., mobile device) connected to receive power from the power adapter. The power adapter includes an adaptive overvoltage protection mode that sets an overvoltage protection threshold to a low level during startup and thereafter sets the overvoltage protection threshold to a higher level after detecting proper operation of the protocol IC.

Abstract: In one embodiment, a power supply controller, or alternately a semiconductor device having a power supply controller, may have a first circuit configured to form a sense signal that is representative of a signal from an auxiliary winding of a transformer. A feedback circuit may be configured to allow the sense signal to increase in response to a turn-off of the power switch, to subsequently detect a second increase of the sense signal prior to subsequently turning on the power switch, and to form a feedback signal as a value of the sense signal responsively to the second increase of the sense signal.

Abstract: A switched-mode power supply with near valley switching includes a quasi-resonant converter. The converter includes a switch element that is turned on not only at the valley, but also in a window range of ?tNVW close to the valley, where the voltage across the switch element is at its minimum. This advantageously reduces switching loss and maintains a balance between efficiency and frequency variation.

Abstract: A switched-mode power supply with near valley switching includes a quasi-resonant converter. The converter includes a switch element that is turned on not only at the valley, but also in a window range of ?tNVW close to the valley, where the voltage across the switch element is at its minimum. This advantageously reduces switching loss and maintains a balance between efficiency and frequency variation.

Abstract: In one embodiment, a power supply controller, or alternately a semiconductor device having a power supply controller, may have a first circuit configured to form a sense signal that is representative of a signal from an auxiliary winding of a transformer. A feedback circuit may be configured to allow the sense signal to increase in response to a turn-off of the power switch, to subsequently detect a second increase of the sense signal prior to subsequently turning on the power switch, and to form a feedback signal as a value of the sense signal responsively to the second increase of the sense signal.

Abstract: An exemplary embodiment of an alternating valley switching controller is provided. The alternating valley switching controller includes a valley detection circuit and an alternating circuit. The valley detection circuit is coupled to an auxiliary winding of a transformer to generate a valley-detection signal. The alternating circuit alternates a plurality of switching periods of a switching signal according to a blanking-window signal and the valley-detection signal. The blanking-window signal switches between a first voltage level and a second voltage level in the plurality of switching periods. The plurality of switching periods includes at least two first periods and at least two second periods which occur alternately in response to the first voltage level and the second voltage of the blanking-window signal.

Abstract: A method for communicating with a power converter comprises initiating a communication sequence by sensing a first distortion of a sensed waveform during a discharge period of a first power transfer cycle of the power converter. The sensed waveform is proportional to a secondary current of the power converter. At a primary side of the power converter, a data bit is received from a secondary side of the power converter, by sensing a second distortion to represent one state of the data bit and sending an absence of the second distortion to represent another state of the data bit. The secondary distortion is applied to the secondary current during the discharge period of a subsequent power transfer cycle.

Abstract: A method for communicating with a power converter comprises initiating a communication sequence by sensing a first distortion of a sensed waveform during a discharge period of a first power transfer cycle of the power converter. The sensed waveform is proportional to a secondary current of the power converter. At a primary side of the power converter, a data bit is received from a secondary side of the power converter, by sensing a second distortion to represent one state of the data bit and sending an absence of the second distortion to represent another state of the data bit. The secondary distortion is applied to the secondary current during the discharge period of a subsequent power transfer cycle.

Abstract: In one embodiment, a power supply controller, or alternately a semiconductor device having a power supply controller, may have a circuit configured configuring the PWM circuit to form a first signal having a value formed to be representative of a peak value of a primary current through the power switch and having a duration that is representative of a time interval that a secondary current is flowing through a secondary winding wherein the peak value is the peak value during an on-time of the power switch, and configured to form a current having a value that is representative of an average value of the secondary current.

Abstract: An electrical circuit for a power supply includes a primary-side controller integrated circuit (IC) that outputs a drive signal on a switch pin to control a switching operation of a switch that is coupled to a primary winding of a transformer. The primary-side controller IC places the switch pin at high impedance during a sense window and turns on the switch in response to sensing a dynamic detection signal on the switch pin during the sense window. The dynamic detection signal is induced by a secondary-side controller IC by controlling switching of a switch that is coupled to a secondary winding of the transformer when the output voltage drops below a predetermined threshold during standby or other low load conditions.