Abstract: A high leakage inductance transformer core device, and method of forming same, that has a core made of tape wound material, at least one set of concentric primary and secondary windings, and at least one flux shunt between the primary and secondary windings which is also made of tape wound material. The transformer core and flux shunts are arranged so that the transformer has a low external magnetic field, and substantially no excess core losses due to principal core flux flowing from one part of the core structure to another through the broad surface of the core tape.

Abstract: A tape wound inductor core device, inductors including same and methods of manufacture. Tape wound material may be cut and/or shaped into “pucks” that have an exterior surface made up of or defined substantially by the edge surfaces of the layers of the constituent conductive material, with all or most of the broad surfaces disposed inwardly, thereby reducing eddy currents and associated losses. Various puck configurations, inductor arrangements and fabrication techniques are disclosed.

Abstract: A high leakage inductance transformer core device, and method of forming same, that has a core made of tape wound material, at least one set of concentric primary and secondary windings, and at least one flux shunt between the primary and secondary windings which is also made of tape wound material. The transformer core and flux shunts are arranged so that the transformer has a low external magnetic field, and substantially no excess core losses due to principal core flux flowing from one part of the core structure to another through the broad surface of the core tape.

Abstract: A tape wound inductor core device, inductors including same and methods of manufacture. Tape wound material may be cut and/or shaped into “pucks” that have an exterior surface made up of or defined substantially by the edge surfaces of the layers of the constituent conductive material, with all or most of the broad surfaces disposed inwardly, thereby reducing eddy currents and associated losses. Various puck configurations, inductor arrangements and fabrication techniques are disclosed.

Abstract: An inductor core device, and method of forming same, that has at least a first inductor core section and typically has a second inductor core section, both formed of stacked layers of conductive material. The second core section may be positioned relative to the first core section to define an air gap therebetween and the sections are preferably profiled between their respective end faces and broad surfaces to reduce the eddy current losses induced in the core section(s) near the air gap. Various embodiments, “profile” shaping configurations, and core section arrangements are disclosed.

Abstract: An inductor core device, and method of forming same, that has at least a first inductor core section and typically has a second inductor core section, both formed of stacked layers of conductive material. The second core section may be positioned relative to the first core section to define an air gap therebetween and the sections are preferably profiled between their respective end faces and broad surfaces to reduce the eddy current losses induced in the core section(s) near the air gap. Various embodiments, “profile” shaping configurations, and core section arrangements are disclosed.

Abstract: A bipolar junction transistor (BJT) used as a controlled rectifier (CR) that is driven and controlled by an electronic circuit, such that when (in a first mode of operation) the collector-emitter voltage (VCE) is above an offset voltage (VCEOS) the circuit drives the base of the SR BJT with a base current proportional to the difference between VCE and VCEOS, turning the CR BJT on with a base current proportional to the collector current. When the VCE of the CR BJT falls below VCEOS the drive circuit turns on a second transistor coupled between the base and collector of the CR BJT to turn the CR BJT rapidly off and maintains it in the off state as the collector voltage reverses. When the VCE of the CR BJT exceeds a threshold voltage above the normal conduction VCE range, the control circuit increases the base drive current to accelerate the CR BJT turn-on process.

Abstract: A controlled rectifier circuit having a BJT implemented as the controlled rectifier (CR) and first and second turn-off transistors coupled respectively between the base and collector and base and emitter of the CR BJT to rapidly remove stored charge from the collector-base junction of that CR BJT. The turn-off transistors may be implemented with BJTs, FETs (or related active electronic devices) and the polarity of the transistors may be the same or opposite to that of the CR BJT. Anti-saturation and drive current amplifying circuitry may be provided. A turn-off drive command may be delivered to an appropriate transistor via steering logic or an auto-steering configuration. The circuit is preferably implemented as an integrated circuit.

Abstract: A bipolar junction transistor (BJT) used as a synchronous rectifier (SR) that is turned off by an active electronic device such as a transistor coupled between the base and collector of that SR BJT. The turn-off transistor functions to rapidly remove stored charge from the collector-base junction of the SR BJT when appropriate. Various active electronic devices are discussed as implementations of the turn-off transistor, including bipolar and field effect transistors of same or opposite polarity. Various anti-saturation and base current increasing circuits are also disclosed.

Abstract: A bipolar junction transistor (BJT) used as a synchronous rectifier (SR) that is driven and controlled by an electronic circuit, such that when the collector-emitter voltage (VCE) is above an offset voltage (VOS) the circuit drives the base of the SR BJT with a base current proportional to the difference between VCE and VOS, turning the SR BJT on with a base current proportional to the collector current. When the VCE of the SR BJT falls below VOS the drive circuit turns on a second transistor coupled between the base and collector of the SR BJT to turn the SR BJT rapidly off and maintains it in the off state as the collector voltage reverses. When the VCE of the SR BJT is exceeds a threshold voltage above the normal conduction VCE range, the control circuit increases the base drive current to accelerate the SR BJT turn-on process.

Abstract: A bipolar junction transistor (BJT) used as a controlled rectifier (CR) that is driven and controlled by an electronic circuit, such that when (in a first mode of operation) the collector-emitter voltage (VCE) is above an offset voltage (VCEOS) the circuit drives the base of the SR BJT with a base current proportional to the difference between VCE and VCEOS, turning the CR BJT on with a base current proportional to the collector current. When the VCE of the CR BJT falls below VCEOS the drive circuit turns on a second transistor coupled between the base and collector of the CR BJT to turn the CR BJT rapidly off and maintains it in the off state as the collector voltage reverses. When the VCE of the CR BJT exceeds a threshold voltage above the normal conduction VCE range, the control circuit increases the base drive current to accelerate the CR BJT turn-on process.

Abstract: A bipolar junction transistor (BJT) used as a synchronous rectifier (SR) that is turned off by an active electronic device such as a transistor coupled between the base and collector of that SR BJT. The turn-off transistor functions to rapidly remove stored charge from the collector-base junction of the SR BJT when appropriate. Various active electronic devices are discussed as implementations of the turn-off transistor, including bipolar and field effect transistors of same or opposite polarity. Various anti-saturation and base current increasing circuits are also disclosed.

Abstract: A controlled rectifier circuit having a BJT implemented as the controlled rectifier (CR) and first and second turn-off transistors coupled respectively between the base and collector and base and emitter of the CR BJT to rapidly remove stored charge from the collector-base junction of that CR BJT. The turn-off transistors may be implemented with BJTS, FETs (or related active electronic devices) and the polarity of the transistors may be the same or opposite to that of the CR BJT. Anti-saturation and drive current amplifying circuitry may be provided. A turn-off drive command may be delivered to an appropriate transistor via steering logic or an auto-steering configuration. The circuit is preferably implemented as an integrated circuit.

Abstract: A bipolar junction transistor (BJT) used as a synchronous rectifier (SR) that is driven and controlled by an electronic circuit, such that when the collector-emitter voltage (VCE) is above an offset voltage (VOS) the circuit drives the base of the SR BJT with a base current proportional to the difference between VCE and VOS, turning the SR BJT on with a base current proportional to the collector current. When the VCE of the SR BJT falls below VOS the drive circuit turns on a second transistor coupled between the base and collector of the SR BJT to turn the SR BJT rapidly off and maintains it in the off state as the collector voltage reverses. When the VCE of the SR BJT is exceeds a threshold voltage above the normal conduction VCE range, the control circuit increases the base drive current to accelerate the SR BJT turn-on process.

Abstract: A switch mode voltage regulator with synchronous rectification that produces ripple cancellation with fast load response is described. The switch mode voltage regulator comprises a main step-down regulator with synchronous rectification with an auxiliary step-down regulator that produces an output ripple cancellation current that is equal but opposite to the output ripple of the main regulator during static load conditions. During changing load conditions a feedback control circuit changes the duty cycle of the main regulator while a time-delay circuit prevents a change of the duty cycle in the auxiliary regulator. Thus, the main regulator is allowed to change its average current while preventing a counteracting average current change in the auxiliary regulator. An embodiment is described in which the duty cycle in the auxiliary regulator is changed in phase with the duty cycle of main regulator to further improve the dynamic response to load changes.

Abstract: A circuit for an inductive current sensor that optimizes waveform fidelity of the inductively sensed current for non-sinusoidal currents is claimed. The circuit employs a high gain op amp to sum the inputs of a feedback capacitor and other feedback impedance components including a second op amp and a capacitor, the values of which are selected to provide a double pole roll-off with a gain peaking Q of between 1 and 10, and an impedance which at the low corner frequency is approximately equal to that of the feedback capacitor. Above the low corner frequency of the sensor, the impedance is sufficiently high to have substantially no effect on the circuit and which decreases below the low corner frequency.

Abstract: Compound inductors for use in switching regulators have two or more symmetrically coupled windings so the component size is reduced as well as a reduction in power losses compared with conventional inductors. The compound inductors may be used in buck and boost regulators. The compound inductor assembly has a first inductor with a first winding on a first magnetic core, a second inductor with a second magnetic core outside the first winding of the first inductor, and a second winding around the first winding of the first inductor and the second core. One end of the first winding and the corresponding end of the second winding is connected to a common connection such that voltages from an alternating current flowing in the first winding have the same polarity in the first winding and in the second winding.

Abstract: A switching regulator for achieving soft switching comprises a pilot switch in series with a diode, and a pilot inductor connected from the junction between the pilot switch and the diode to a tap on the main inductor. A bidirectional circuit operating as a buck or a boost regulator can be achieved by replacing all of the diodes with active switches and selectively activating certain of the switches.

Abstract: A physically integrated assembly of tow magnetically independent transformers and two semiconductor rectifiers, arranged to minimized leakage and parasitic lead inductances, and the resultant voltage dropout during current commutation from one transformer-rectifier to the other. In a suitable circuit this assembly produces a nearly pure DC output voltage, which requires a minimum amount of filtering. It is also possible, when a choke input filter is required in the output, to integrate the filter choke into the same physical assembly, using part of the existing tranformer core material. The choke is magnetically independent of the transformers.