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.

A control unit determines a polarity of an actual voltage value of an AC power supply if it is either positive or negative based on a detection voltage thereof detected by the voltage detector. The control unit alternately actuates a set of a first switch and a fourth switch and another set of the second switch and a third switch each time when it is determined that the polarity of the actual voltage value of the AC power supply changes. A second reactor is disposed at at least one of first and second positions. The first position is located between a first AC side terminal and a connection point located between the first switch and the second switch. The second position is located between a second AC side terminal and a connection point located between the third switch and the fourth switch.

A full-wave rectifier is disclosed. In one embodiment the full-wave rectifier includes two input paths configured to receive an alternating input voltage, two output paths configured to provide a direct output voltage, and four switched-mode rectifying paths that are connected between each of the input paths and each of the output paths, wherein the switched mode rectifying paths are configured to connect a first input path to a first output path and a second input path to a second output path during a first half wave of the input voltage, and to connect the first input path to the second output path and the second input path to the first output path during a second half wave of the input voltage, and wherein the switched-mode rectifying paths include cascode circuits.

A rectifier cell includes a first cell branch and a second cell branch that extend in parallel between two opposite nodes receiving an a.c. signal. The first cell branch includes a first pair of transistors arranged with their current paths cascaded, with a first intermediate point in-between. The second cell branch includes a second pair of transistors arranged with their current paths cascaded, with a second intermediate point in-between. Each of the pairs of transistors includes a first transistor with a control terminal coupled to one of the two opposite nodes and a second transistor with a control terminal coupled to the other of the two opposite nodes. The bulks of the transistors receive voltages in order to vary the transistor threshold voltage by bringing the threshold voltage to a first value during forward conduction and to a second value during reverse conduction.

The control apparatus is used with the electrical power converter working to an inputted one of ac voltage and a terminal-to-terminal voltage at a capacitor into the other. The control apparatus calculates a sine-wave command value for a reactor current based on the ac voltage and an amplitude command value indicating an amplitude of the reactor current. The control apparatus also operates switches SW in peak-current mode control to bring the reactor current into agreement with a command value for the reactor current to which a current correction value is added. The control apparatus sets the current correction value to include a component of fluctuation in the terminal-to-terminal voltage at the capacitor based on the ac voltage Vac.

Methods and apparatus are disclosed for wirelessly receiving power. In one aspect, an apparatus for wireless receiving power is provided. The apparatus comprises a receive circuit configured to receive wireless power via a magnetic field sufficient to power or charge a load. The apparatus further comprises a synchronous rectifier electrically coupled to the receive circuit, the synchronous rectifier comprising a switch and configured to rectify an alternating current (AC) signal, generated in the receive circuit, to a direct current (DC) signal for supplying power to the load. The apparatus further comprises a controller configured to, during a period when an input voltage level of the synchronous rectifier is higher than an output voltage level of the synchronous rectifier, adjust a conduction angle of the switch at a first frequency substantially in phase with a frequency of the AC signal to adjust an output power to the load.

A semi-active bridge for furnishing voltage of a correct polarity to a powered device in a Power over Ethernet (PoE) network is disclosed. In one or more implementations, the semi-active bridge includes a diode having an anode portion and a cathode portion. The anode portion of the diode is connected to an input terminal, and the cathode portion of the diode is connected to an output terminal. The semi-active bridge also includes an active transistor device having a source region and a drain region. The drain region of the active transistor device is connected to the input terminal, and the source region of the active transistor device is connected to the output terminal.

A hand tool battery includes a charging coil and a bridge rectifier. The bridge rectifier has at least two rectifying arrangements for synchronous rectification.

An active rectifier and a wireless power reception apparatus using the same are disclosed herein. The active rectifier includes first and fourth switches, second and third switches, and a synchronization control unit. The first and fourth switches are turned on while the voltage of an alternating current (AC) input is negative, and apply the current of the AC input to a rectifying capacitor. The second and third switches are turned on while a voltage of the AC input is positive, and apply the current of the AC input to the rectifying capacitor. The synchronization control unit compensates for the delay time of the comparator for detecting zero-crossing of the AC input so as to switch the first to fourth switches.

A wireless power receiver circuit forms a wireless power receiving apparatus together with a reception coil. An internal power supply line is connected to a capacitor C. An output line is connected to a secondary battery. An H-bridge circuit includes N-channel MOSFETs MH1, MH2, ML1, and ML2. A first switch is arranged between a rectification line and the internal power supply line. A second switch is arranged between the rectification line and the output line. A voltage V.sub.DD of the internal power supply line is supplied to a power supply terminal of a controller.