Disclosed is a converter circuit having high power in an ultra-wide range, which includes a transformer module, a first and second primary input modules, an output module, a high and low voltage mode control module, and a load output module. The first primary input module includes a first primary voltage equalization network, a first switch module and a first LC module, the second primary input module includes a second primary voltage equalization network, a second switch module and a second LC module. The first primary voltage equalization network is connected between a first input capacitor and the second switch module, and the second primary voltage equalization network is connected between a second input capacitor and the first switch module. In this disclosure, it is surprisingly found that through arranging resonant voltage equalization network, a designated primary voltage deviation problem, which is caused by a change of a pulse control of an LLC resonant converter under a light load, is solved.

An embodiment apparatus includes a converter including a plurality of switching elements configured as a bridge circuit connected to an input terminal and having a plurality of bridge arms, wherein a topology of the converter is configured to be switchable to a full-bridge type topology or a half-bridge type topology, and wherein a resonant capacitor is connected to a midpoint between respective ones of the bridge arms, and a controller configured to switch the topology of the converter to the full-bridge type or the half-bridge type by controlling whether the resonant capacitor is activated based on a load current of the converter.

A wireless power transfer system comprises a power transmission device and a power reception device. The power reception device includes a power reception coil that wirelessly magnetically couples with a power transmission coil included in the power transmission device. The power transmission device includes a switching circuit in which switch elements perform switching operations, an input voltage adjustment circuit that is electrically connected to the switching circuit and adjusts an input voltage, and an MPU. The MPU is configured to recognize a power requirement presented by the power reception device, control the input voltage adjustment circuit and control intermittent oscillation of the switching circuit, and adjust the input voltage to prevent an oscillation stop period of the intermittent oscillation from exceeding a predetermined stop period.

A power converter a transformer, a switching bridge circuit, a resonant tank circuit, an output rectifier, and a controller. The switching bridge circuit a plurality of switches, each switch controllable into a conduction mode and into a non-conduction mode. The controller is configured to control the plurality of switches based on a series of phase shift modulation switching cycles, each cycle comprising a control period and a delay period. During the control period, the controller causes the conduction mode of each switch of the plurality of switches to overlap a portion of each conduction mode of two other switches. During the delay period, the controller controls all of the switches into non-conduction modes overlapping in time.

An apparatus, such as an image forming apparatus, includes a Universal Serial Bus (USB) host interface configured to connect to a USB device, a direct current to direct current (DC-DC) converter configured to supply power to the USB device connected to the USB host interface, and a control unit configured to switch the DC-DC converter from a pulse width modulation (PWM) mode to a pulse frequency modulation (PFM) mode based on a type of the USB device connected to the USB host interface.

An apparatus, such as an image forming apparatus, includes a Universal Serial Bus (USB) host interface configured to connect to a USB device, a direct current to direct current (DC-DC) converter configured to supply power to the USB device connected to the USB host interface, and a control unit configured to switch the DC-DC converter from a pulse width modulation (PWM) mode to a pulse frequency modulation (PFM) mode based on a type of the USB device connected to the USB host interface.

A system is disclosed. The system includes a substrate, and a first chip on the substrate, where a load circuit is integrated on the first chip. The system also includes a second chip on the substrate, where a power delivery circuit is configured to deliver current to the load circuit according to a regulated voltage at a node. The power delivery circuit includes a first circuit configured to generate an error signal based at least in part on the regulated voltage, and a voltage generator including power switches configured to modify the regulated voltage according to the error signal, where the first circuit of the power delivery circuit is integrated on the first chip, and where at least a portion of the power switches of the power delivery circuit are integrated on the second chip.

A resonant switching power converter includes: capacitors, switches, at least one charging inductor, at least one discharging inductor and a pre-charging circuit. The pre-charging circuit controls a first switch of the switches when the resonant switching power converter operates in a pre-charging mode, to control an electrical connection relationship between the input voltage and a first capacitor of the capacitors and to control other capacitors of the capacitors, thus controlling the capacitors to be connected in parallel to one another or to be connected in series to one another, so that when a voltage drop across the first capacitor is lower than a predetermined voltage, the voltage drop across each capacitor is charged to the predetermined voltage. After operating in the pre-charging mode, the resonant switching power converter subsequently operates in a resonant voltage conversion mode, to thereby convert an input voltage to an output voltage.

An inline DC feeder DC/DC voltage step-up harness for photovoltaic solar facilities includes a housing, a plurality of PV input connectors, an at least one PV output connector. The housing incorporates a DC/DC converter, and has an input and an output. The plurality of PV input connectors are operatively connected to the housing at the input. The PV output connector is operatively connected to the housing at the output.

A semiconductor device includes first and second electrodes, a semiconductor part therebetween, and a control electrode between the semiconductor part and the first electrode. The semiconductor part includes first, third and fifth layers of a first conductivity type and second and fourth layers of a second conductivity type. The second layer is provided between the first layer and the first electrode. The third layer is provided between the second layer and the first electrode. The fourth layer and the fifth layer are selectively provided between the first layer and the second electrode. In a method for controlling the semiconductor device, first to third voltages are applied in order to the control electrode while a p-n junction between the first and second layers is biased in a forward direction. The second and third voltages are greater than the first voltage, and the third voltage is less than the second voltage.