Abstract: In certain examples, methods and semiconductor structures are directed to a switching (power) amplification circuit, including resonance circuitry to resonate at a frequency associated with at least one of a plurality of different selectable resonance frequencies. The switching amplification circuit is configured to deliver power to one or multiple loads while the switching amplifier circuit is operating based on one or more of the selectable resonance frequencies.

Abstract: In certain examples, methods and semiconductor structures are directed to circuit-based apparatus in which an amplifier includes stacked, first and second circuit amplification stages to operate out of phase from one another for providing a push-pull operation, with each of the first and second circuit stages including a switching circuit and an impedance path to drive the switching circuit. The apparatus further includes a waveform-shaping circuit to shape, in response to each of the first and second circuit stages, a voltage signal for presentation to the switching circuit. As may be implemented in various more-specific examples, the apparatus may generate a constant output voltage with high efficiency across a wide range of resistive loads.

Abstract: Exemplary aspects are directed to a power-amplification circuit including multiple in-parallel circuit paths, each including a power amplifier driving an immittance converter. Current from each output of the respective immittance converters is combined for delivery to a load. In a more specific example, a control circuit may be used to modulate, such as by enabling or disabling power delivered from, one or more of the power amplifiers for fast, coarse resetting of the overall power delivered to the load, and/or to modulate one or more of the modulate immittance converters (e.g., via a phase or signal-timing adjustment) to finely tune the resetting of the overall power delivered to the load. Using the control circuit for providing both the coarse adjustment and the fine adjustment, and fast acting precise delivery of overall power delivered to a load may be realized for any of a variety of applications.

Abstract: In certain examples, the disclosure involves or is directed to a circuit-based apparatus that has a T-network, and a plurality of circuit paths with a first path having a first switching node to respond to an RF input signal that is characterized by a first phase, and with a second path having a second switching node to respond to the RF input signal characterized by a second phase that is different than the first phase. The circuit paths may be configured as a push-pull amplification circuit. The T-network may be arranged between the first and second switching nodes and may include a variable impedance circuit. The variable impedance circuit may be adjusted, in accordance with a selected frequency of the RF input signal. The T-network may be characterized by a resonance frequency shunts a second harmonic current associated with the resonance frequency, thereby permitting for use of different selected frequencies.

Abstract: In specific examples, aspects are directed towards eliminating, mitigating or reducing gate loss in circuits including, for example, WBG power devices. One such example is directed towards an apparatus including first and second types of field-effect transistor (FET), where the first type is characterized as being a normally-on FET in a switching-circuit operation with a high-voltage rating, and the second type of FET is characterized as being a normally-off FET in a switching-circuit operation with a voltage rating that is much less than the high-voltage rating of the first type of FET circuit. The FET are arranged in a cascode manner so that, in response to a switching control signal received by the second type of FET circuit, the second type of FET circuit is active to drive the first type of FET.

Abstract: Exemplary aspects are directed to a power-amplification circuit including multiple in-parallel circuit paths, each including a power amplifier driving an immittance converter. Current from each output of the respective immittance converters is combined for delivery to a load. In a more specific example, a control circuit may be used to modulate, such as by enabling or disabling power delivered from, one or more of the power amplifiers for fast, coarse resetting of the overall power delivered to the load, and/or to modulate one or more of the modulate immittance converters (e.g., via a phase or signal-timing adjustment) to finely tune the resetting of the overall power delivered to the load. Using the control circuit for providing both the coarse adjustment and the fine adjustment, and fast acting precise delivery of overall power delivered to a load may be realized for any of a variety of applications.

Abstract: In specific examples, aspects are directed towards eliminating, mitigating or reducing gate loss in circuits including, for example, WBG power devices. One such example is directed towards an apparatus including first and second types of field-effect transistor (FET), where the first type is characterized as being a normally-on FET in a switching-circuit operation with a high-voltage rating, and the second type of FET is characterized as being a normally-off FET in a switching-circuit operation with a voltage rating that is much less than the high-voltage rating of the first type of FET circuit. The FET are arranged in a cascode manner so that, in response to a switching control signal received by the second type of FET circuit, the second type of FET circuit is active to drive the first type of FET.

Abstract: Methods and apparatus for a dc-dc converter for operating at substantially fixed switching frequency, the converter including a rectifier, and a resonant inverter coupled to the rectifier, the resonant inverter including a switch and a reactive network having first, second, third and fourth energy storage elements, wherein an impedance magnitude at the output of the switch due to the reactive network has minima at dc and at a frequency near a second harmonic of the switching frequency.

Abstract: A resistance compression network substantially decreases the variation in effective resistance seen by a tuned rf inverter as loading conditions change. Circuits can include resistance compression networks and rectifiers to form rf-to-dc converters having narrow-range resistive input characteristics.

Abstract: A switched mode dc-dc converter enables increases in switching frequency over conventional architectures. In one embodiment, a dc-dc converter has a Vernier-regulated architecture having unregulated cells and a regulating cell coupled to a controller. In another embodiment, a dc-dc-converter has a cell-modulation-regulated architecture.

Abstract: An expandable, self-fastening strap includes a pair of fastening ends separated by a band, at least a portion of which is expandable. Located on one of the fastening ends is an eyelet. At least a portion of the laces of a boot may be forwarded through the eyelet. The strap and lace combination is wrapped around the boots, with the strap covering the laces, until the fastening ends of the strap meet. The fastening ends are then fastened together. Because at least a portion of the band is expandable, when the band is wrapped around the boot pressure is placed upon the laces, thereby precluding them from slipping under the strap. The strap thus secures the laces without undesirably constricting circulation of the wearer. As a result, wearer fatigue and discomfort is reduced. In addition, because the strap is tightly affixed to the boot, the device presents no extraneous protrusions that may become entangled in machinery or the like.