An apparatus attachable to a luminaire includes circuitry for converting alternating current power into direct current (DC) power and providing a digitally stable ground for operation of a processor-based device. The circuitry includes a transformer isolating a primary side from a secondary side of the circuitry. A switching controller (e.g., a pulse width modulation controller) on the primary side directs a switching circuit to selectively permit current flow through a primary side of the transformer to a first ground node. A secondary winding of the transformer sources a rectified DC output relative to a second ground node that is isolated from the first ground node. In some cases, compensation on the secondary winding side provides isolated feedback to the controller, such as via an optical isolator. The controller directs the switching circuit based at least partially on the feedback and input from an auxiliary winding of the transformer.

A switching converter includes: a reactor having one end to be connected to an AC power source; and a rectifier circuit connected to an opposite end of the reactor, the rectifier circuit converting a power source voltage applied by the AC power source into a DC voltage. The rectifier circuit includes a first leg and a second leg connected in parallel to the first leg. The first leg includes a first upper-arm element and a first lower-arm element connected in series. The second leg includes a second upper-arm element and a second lower-arm element connected in series. A snubber circuit including a resistor and a capacitor is connected to each of upper and lower-arm elements in one of the first and second legs. No snubber circuit is connected to upper and lower-arm elements in another of the first and second legs.

System and method for controlling synchronous rectification. For example, a system for controlling synchronous rectification includes: a first control-signal generator configured to generate a first control signal; a second control-signal generator configured to receive the first control signal for a first switching cycle and generate a second control signal for a second switching cycle based at least in part on the first control signal for the first switching cycle, the first switching cycle preceding the second switching cycle; and a driver configured to receive the first control signal and generate a drive voltage based at least in part on the first control signal; wherein the second control-signal generator is further configured to: process information associated with the first control signal; determine a first time duration when the first control signal remains at a first logic level during the first switching cycle.

The subject application provides a power converter with lossless current sensing capability. The power converter comprises: a transformer, a primary switch for conducting or blocking a current flowing in a primary winding of the transformer, a controller configured to generate a first control signal through a first control node to control the primary switch; and a current sensing circuit configured for sensing a current flowing in the primary winding. The current sensing circuit comprises a current sensing switch that is configured to be normally open and has a gate length smaller than a gate length of the primary switch. A relatively simple current sensing circuit is achieved and the overall power efficiency is improved.

A snubber circuit includes a snubber substrate including an electrically insulating carrier and an electrically conducting structured layer applied thereon, the electrically conducting structured layer including two segments. The snubber circuit further includes two electrically resistive layers, each resistive layer being applied onto the two segments of the electrically conducting structured layer of the snubber substrate, and a capacitor disposed on the electrically resistive layers and having two terminals, each terminal being electrically connected to one of the electrically resistive layers. Further, a power semiconductor module having such a snubber circuit is disclosed.

Disclosed herein is a semiconductor device configured by packaging a semiconductor chip, including at least one terminal. The semiconductor chip includes a pad connected to the terminal, a voltage clamp unit, and a wiring disposed along an outer periphery of the semiconductor chip and between the voltage clamp unit and the pad. In a case in which the wiring has no broken wire portion, a terminal voltage generated at the terminal is clamped to a clamp voltage by the voltage clamp unit, and in a case in which the wiring has a broken wire portion, the terminal voltage reaches a predetermined voltage higher than the clamp voltage or a predetermined voltage lower than the clamp voltage.

A small cell networking device mountable to a streetlight fixture includes circuitry for converting alternating current power into direct current (DC) power and providing a digitally stable ground for operation of the small cell device. The circuitry includes a transformer isolating a primary side from a secondary side of the circuitry. A switching controller on the primary side directs a switching circuit to selectively permit current flow through a primary side of the transformer to a first ground node on the primary side. A secondary winding of the transformer sources a rectified DC output relative to a second ground node that is isolated from the first ground node. In some cases, compensation on the secondary winding side provides isolated feedback to the controller, such as via an optical isolator. The controller directs the switching circuit based at least on the feedback and input from an auxiliary winding of the transformer.

Power converting devices (100) for power tools. One embodiment provides a power converter device (100) including a power source (200), a power converter (210) coupled to the power source (200), and an electronic processor (220) coupled to the power converter (210) to control the operation of the power converter (210). The power converter (210) is configured to receive an input power in one form or at a first voltage from the power source and convert the input power to an output power in another form or at a second voltage. The power converter (210) includes at least one wide bandgap field effect transistor controlled by the electronic processor (220) to convert the input power to output power.

An air conditioning device includes a buck converter which comprises a switching device, an inductor, a diode and at least one capacitor. The diode is a SiC diode, and the buck converter further includes an attenuator associated to the SiC diode and a ferrite bead associated to the switching device.

A line interface filter apparatus to couple a drive or group of drives to a shared multiphase AC bus, including individual phase circuits having an inductor coupled between a respective bus and drive phase lines, a tapped resistor coupled to the respective drive phase line, and a capacitor coupled between the resistor and a common connection of the capacitors of the individual phase circuits, where the capacitance of the capacitors is 5 to 15 times a per-phase equivalent capacitance of the drive or group of drives, and the resistance of the resistors is two times a damping ratio times a square root of a ratio of the filter inductance to the filter capacitance, where the damping ratio ζ is greater than or equal to 1.0 and less than or equal to 2.0.