An integrated cinema amplifier comprises a power supply stage that distributes power over a plurality of channels for rendering immersive audio content in a surround sound listening environment. The amplifier automatically detects maximum and net power availability and requirements based on audio content by decoding audio metadata and dynamically adjusts gains to each channel or sets of channels based on content and operational/environmental conditions. A power supply stage provides power to drive a plurality of channels corresponding to speaker feeds to a plurality of speakers. The amplifier has a front panel having an LED array with each LED associated with a respective channel or group of channels of the multi-channel amplifier, and a control unit configured to light the LEDs according to display patterns based on operating status or error conditions of the amplifier.

A switching power supply device includes a power factor improvement circuit, a phase-shifted full bridge type DC/DC converter that is arranged in a rear stage of the power factor improvement circuit and has a full-bridge type switching circuit, an output current detecting circuit for detecting an output current to be supplied to a load, an output voltage detecting circuit for detecting an output voltage to be supplied to the load, and a power factor improvement circuit output voltage detecting circuit for detecting a power factor improvement circuit output voltage, which is input from the power factor improvement circuit to the DC/DC converter. The switching power supply device further includes a control unit for dynamically changing dead times of the full-bridge type switching circuit based on the power factor improvement circuit output voltage, and the output current and the output voltage to be supplied to the load, and the control unit applies the dead times that have been changed to control switching of the full-bridge type switching circuit.

According to one embodiment, there is provided a power converter including a totem-pole power factor correction circuit that can achieve reduction in recovery loss with a simple structure. A power converter according to an embodiment includes a totem-pole power factor correction circuit, a series connection of a first current detector and a second current detector, and a control circuit.

A power conversion apparatus sets a point between AC input terminals of a full-wave rectifying circuit as an input terminal of an alternating voltage, connects a series circuit of two capacitors between the input terminals, connects a series circuit of two switches between DC output terminals of the full-wave rectifying circuit, connects one end of a series circuit of a third capacitor and an inductor with a midpoint of the two switches, connects the other end thereof with a connection point of two capacitors, connects a positive electrode side terminal of a smoothing capacitor with a DC output terminal of a positive electrode of the full-wave rectifying circuit via a first diode, connects a negative electrode side terminal of the smoothing capacitor with a DC output terminal of a negative electrode of the full-wave rectifying circuit via a second diode for preventing counter current.

An illumination device is provided. The illumination device includes a light emitting source and a clamped series resonant converter (CSRC) coupled thereto. The CSRC includes a first rectifier to generate a direct current (DC) using an alternating current (AC) voltage. The CSRC further includes an inverter having a switching leg including a plurality of switches coupled in series and a diode leg having a plurality of diodes coupled in series. The diode leg is coupled in parallel with the switching leg. Furthermore, the inverter includes an inductor coupled to the switching leg and a capacitor coupled to the diode leg. The CSRC also includes a transformer coupled to the inverter, where a voltage developed across a primary winding of the transformer causes automatic power factor correction by drawing an input current flowing through the CSRC that is proportional to the AC voltage.

A resonant induction wireless power transmission apparatus having intrinsic line power factor correction provides a method of wireless transmission with a near unity power factor, low harmonic distortion load at the line connection point without employing specific power factor correction circuitry. The apparatus provides a transmission frequency inverter operated with a rectified sinusoidal supply voltage instead of a conventional direct current voltage. The resonant induction transfer coil pair is transformed into an impedance inverter by addition of two series connected resonating capacitors of specific value. The impedance inverter raises the secondary side voltage under conditions of light loading and in this way forces line frequency source current and secondary side load current to be proportional, thereby maintaining near unity line load power factor and low harmonic current distortion.

A high-power power supply for use with display devices and an associated display device are provided. The high-power power supply includes an AC conversion module configured to rectify an external AC source into a DC output, a power factor correction circuit configured to perform power factor correction to the DC output and output a correction completion signal when the correction is completed, a power-on control circuit configured to control the power factor correction circuit to be turned on to perform the power factor correction to the DC current when receiving a power-on signal and to control multiple resonance control circuits to be turned on when receiving the correction completion signal, a plurality of resonance control circuits configured to, when turned on, control multiple transformers to operate normally, and multiple transformers configured to supply different operating voltages to the display device. The present disclosure has the advantage of low cost.

A driver device (10) for driving a load (22), in particular for driving an LED unit comprising one or more LEDs is presented. The driver device comprises input terminals (12, 14) for connecting the driver device to an electrical power supply (16) for receiving a variable input voltage (V10) from the electrical power supply, a converter unit (25) for converting the input voltage (V10) to an output voltage (V12) including a resonant converter (40) and a switch unit (26), wherein the switch unit is adapted to provide a chopped voltage of the input voltage as a drive voltage (V16) to the resonant converter, and a control unit (34) connected to the switch unit for controlling a pulse frequency (f.sub.P) of the chopped voltage, wherein the control unit is adapted to control an input current (I10) drawn from the electrical power supply by controlling the pulse frequency of the chopped voltage on the basis of a measured value of the variable input voltage.

A power converter for converting DC power to DC power includes an inverter stage having two or more switched inverters configured to receive DC power from a source and produce a switched AC output power signal. A transformation stage is coupled to receive the switched output power signal from the inverter stage, shape the output power signal, and produce a shaped power signal. A rectifier stage having two or more switched inverters coupled to receive the shaped power signal and convert the shaped power signal to a DC output power signal is included. A controller circuit is coupled to operate the power converter in a variable frequency multiplier mode where at least one of the switched inverters is switched at a frequency or duty cycle that results in an output signal having a frequency that is a harmonic of the fundamental frequency being generated by the power converter.

The disclosed embodiments provide an AC/DC power converter that converts an AC input voltage into a DC output voltage. This AC/DC power converter includes an input rectifier stage which rectifies an AC input voltage into a first rectified voltage. The AC/DC power converter also includes a switching resonant stage which is directly coupled to the output of the input rectifier stage. The switching resonant stage converts the rectified voltage into a first high frequency AC voltage of a first amplitude. This AC/DC power converter additionally includes a transformer which is coupled to the output of the switching resonant stage and is configured to down-convert the first high frequency AC voltage into a second high frequency AC voltage of a second amplitude. Furthermore, the AC/DC power converter includes an output rectifier stage which is coupled to the output of the transformer, wherein the output rectifier stage rectifies the second high frequency AC voltage into a DC output voltage.