Abstract: A switching circuit has an active switch, a controller, and at least two terminals. The at least two terminals include two current control terminals for connection at two locations in another circuit. The controller is configured to turn the active switch off to block current between the two locations when the voltage between the two locations is of a first polarity and otherwise to turn the active switch on to conduct current between the two locations, whether or not the two current control terminals are the only ones of the at least two terminals that are connected to the other circuit.

Abstract: Low-loss, common-source gate-control topologies may be used to efficiently drive a multiplicity of switches at frequencies greater than 1 MHz and over a range of duty cycles, including 50%. The control switches can be controlled at high speed using simple, directly-coupled drive circuitry. The gate control topology provides for ZVS of control switches and of primary and synchronous rectifier switches while also eliminating essentially all losses associated with the charging and discharging of gate capacitances of the primary and synchronous switches. The overall switching losses in the converter are reduced to the conduction losses in the channels of the switches enabling high operating frequencies to be achieved at high conversion efficiency. An inductive clamp circuit may be incorporated across a winding to provide a low-loss, common source gate drive topology for complementary switches having different duty cycles and an aggregate duty cycle less than 100%.

Abstract: Modulation control circuitry modulates the equivalent output resistance of a power converter, for example a Sine Amplitude Converter, by varying the ON resistance of the primary switches in the converter. The modulation control circuitry may be used to “soft-start” the converter, perform output current limiting, and to improve current sharing between converters in a power sharing array. Soft-start may be achieved by controlling the rate of rise of the peak voltage applied to the gate control inputs of the primary switches. As the gate voltage passes through a range near the threshold voltage of the primary switches, the ON resistance of the switches, and the equivalent output resistance of the converter, will vary smoothly from a relatively high value to a relatively low value. Current limiting may be accomplished by measuring the output current of the converter and controlling the gate voltages of the main switches in order to keep the current at or below a predetermined level.

Abstract: A Factorized Power Architecture (“FPA”) method and apparatus includes a front end power regulator (“PRM) which provides one or more controlled DC bus voltages which are distributed through the system and converted to the desired load voltages using one or more DC voltage transformation modules (“VTMs”) at the point of load. VTMs convert the DC bus voltage to the DC voltage required by the load using a fixed transformation ratio K=Vout/Vin and with a low output resistance. VTMs exhibit high power density, efficiency and, owing to their inherent simplicity and component utilization, reliability. VTMs may be paralleled and share power without dedicated protocol and control interfaces, supporting scalability and fault tolerance. Feedback may be provided from a feedback controller at the point of load to the front end or to upstream, on-board power regulator modules (“PRMs”) to achieve precise regulation.

Abstract: Protection and filtering functions are provided for external circuits by internal circuits that use controlled elements.

Abstract: A circuit on a circuit board is encapsulated using a first mold section and a second mold section. The first mold section closes on one side of the board, and the first mold section has an exposed first conduit. The second mold section closes on another side of the board, and the second mold section has a second conduit for pushing molding compound into a mold cavity in at least one of the mold sections. The second conduit has a side opened to the first mold section when the first and section mold sections are closed on the circuit board. A piston extends through the first conduit to close the side of the second conduit.

Abstract: A transformer in which a magnetic medium provides flux paths within the medium, two or more windings enclose the flux paths at separated locations along the paths, and an electrically conductive medium, arranged in the vicinity of the magnetic medium and the windings, defines a boundary within which flux emanation from the magnetic medium and the windings is confined and suppressed. In a transformer constructed in accordance with the present invention, both controlled values of leakage inductance and the benefits of separated windings can be achieved. The conductive medium can be configured to reduce the leakage inductance of a controlled-leakage inductance transformer (e.g. for use in a zero-current switching power converter), having separately located windings, by at least 25%, and can be configured to reduce the leakage inductance of a low-leakage inductance transformer (e.g. for use in a PWM power converter), having separately located windings, by at least 75%.

Abstract: A circuit board has a hole that is large enough to accommodate a portion of an electronic component. Contacts are arranged along a side wall of the accommodated portion of the component. Other contacts are mounted on the board and exposed along the periphery of the hole. The contacts on the component (the first contacts) and the contacts on the board (the second contacts) are arranged to effect electrical contact between the first contacts and the second contacts for a range of positions of the component along a direction perpendicular to the board. A connector for making electrical connection includes a connector body supporting the second contacts in a manner that provides mechanically compliant sliding contact between the first contacts and the second contacts when the component is mounted, and a mechanism that enables the connector to be attached to the board by surface mount soldering.

Abstract: Passive circuitry for controlling the current drawn from an AC line and delivering a rectified voltage to a load includes a bridge rectifier, a filter capacitor, a range selector switch for configuring the rectifier and filter capacitor in either a full wave rectification or a voltage doubling configuration, and inductances between the rectifier and the capacitor. Inductances may be alternatively connected between the AC line and the rectifier. A high packing density coupled inductor includes a thermally conductive encapsulant and base plate for removing heat from the inductor allowing smaller inductors to be used to achieve greater power densities. A universal passive current control module includes two input terminals for connection to the AC input, a positive output terminal and a negative output terminal for connection to a load, a third output terminal for connection to a filter capacitance, and a thermally conductive encapsulant for filling the free space within the module.

Abstract: A bobbin is adapted to support a winding on a permeable core and has a wall that provides a confined thermally conductive channel that causes conduction of heat along a predetermined path from the core to a location outside the winding. A value of magnetizing inductance in a transformer is set by adjusting the gap until the value of magnetizing inductance has been set and attaching a segment of the bobbin to a pair of core pieces to maintain the gap. A permeable slug provides a permeable path outside of the hollow interior space and does not couple the winding, and an electrically insulating coupler is interposed between the slug and the winding to electrically insulate the winding.

Abstract: A bobbin is adapted to support a winding on a permeable core and has a wall that provides a confined thermally conductive channel that causes conduction of heat along a predetermined path from the core to a location outside the winding. A value of magnetizing inductance in a transformer is set by adjusting the gap until the value of magnetizing inductance has been set and attaching a segment of the bobbin to a pair of core pieces to maintain the gap. A permeable strip provides a permeable path outside of the hollow interior space and does not couple the winding, and an electrically insulating coupler is interposed between the slug and the winding to electrically insulate the winding.

Abstract: A power converter assembly includes a heat sinking plate, a circuit board structure having a side that faces and is spaced by a gap from a surface of the heat sinking plate that is nearer to said side, a relatively thin, high heat density, dissipative semiconductor component mounted on said side, an encapsulating material filling the gap, and relatively taller, lower heat density, components mounted on the other side of the circuit board, the gap being characterized by an average thermal-resistance of less than 1° C.−in2/Watt.

Abstract: An apparatus includes (a) switching power conversion circuitry including an inductive element connected to deliver energy via a unidirectional conducting device from an input source to a load during a succession of power conversion cycles, and circuit capacitance that can resonate with the inductive element during a portion of the power conversion cycles to cause a parasitic oscillation, and (b) clamp circuitry connected to trap energy in the inductive element and reduce the parasitic oscillation.

Abstract: Heat is conducted, from a heat generating electronic device that is mounted in a gap between a circuit board and a heat dissipator, along a path that includes a path segment that passes along conductive runs on the circuit board and another segment that spans the gap at a location adjacent to the device, the other path segment being spanned predominantly by a non-metallic piece that has a thermal conductivity of at least 7 W/m-°K.

Abstract: A switching circuit has an active switch, a controller, and at least two terminals. The at least two terminals include two current control terminals for connection at two locations in another circuit. The controller is configured to turn the active switch off to block current between the two locations when the voltage between the two locations is of a first polarity and otherwise to turn the active switch on to conduct current between the two locations, whether or not the two current control terminals are the only ones of the at least two terminals that are connected to the other circuit.

Abstract: A power converter includes a housing, heat generating circuitry in the housing, and a heat conducting metal sheath on the outside of the housing. The housing has an elongated-box shape including two relatively smaller ends and four relatively larger sides and a heat-conducting metal sheath on the outside of the housing. The heat conducting sheath covers substantially all of the four relatively larger sides.

Abstract: Apparatus (and a method) useful in a switching power converter having a transformer and a primary switch for connecting a DC input source to a primary winding of the transformer during a portion of each of a succession of converter operating cycles, the apparatus includes a reset capacitor and a reset switch. Reset circuitry cooperates with the reset switch to connect and disconnect the reset capacitor in a manner which provides for resetting the transformer and which allows a current having a non-zero average value to flow in the reset switch. Another aspect is a method for limiting the slew rate in a switching power converter which includes a transformer and a reset circuit of the kind which non-dissipatively recycles the magnetizing energy stored in a transformer during each of a succession of converter operating cycles.

Abstract: An apparatus includes (a) switching power conversion circuitry including an inductive element connected to deliver energy via a unidirectional conducting device from an input source to a load during a succession of power conversion cycles, and circuit capacitance that can resonate with the inductive element during a portion of the power conversion cycles to cause a parasitic oscillation, and (b) clamp circuitry connected to trap energy in the inductive element and reduce the parasitic oscillation.