Abstract: Methods and apparatuses for performing highly accurate surgery using a finite element model coupled with ultrasonic tracking are described.

Abstract: Disclosed are embodiments of methods and systems for wireless data transmission by magnetic induction. In one embodiment, a network of magnetic induction units is provided. The units may be configured to transmit a data signal by modulation of a time-varying magnetic field. One or more units may also be configured to receive a data signal received from another magnetic induction unit. In one specific implementation, a network of underground magnetic induction units is provided, each having a sensor connected thereto. Each of the units, or a subset of the units, may be configured to transmit its sensed data to an adjacent or nearby unit, which, in turn, may retransmit the original data, along with additional appended data, to another adjacent unit. The network data may thereby be relayed in a multi-hop fashion until it reaches a desired destination.

Abstract: A human interface device with an inherent built-in feedback mechanism for use by a user to remotely interface with a computer-simulated environment is disclosed herein. The human interface device comprises at least one sensor configured to sense a condition within the action of the computer-simulated environment and also operable to generate a communication concerning the sensed condition. At least one micro-controller is positioned within the human interface device and configured to receive the communication concerning the sensed condition from the at least one sensor. The at least one micro-controller is further configured to generate communication in reaction to the communication from the sensor. At least one actuator is configured to receive the communication from the at least one micro-controller and provide a sensory experience in reaction to the communication.

Abstract: A system and method are disclosed for utilizing resources of a network. A constructive proof that a subset of resources is sufficient to satisfy the objective of a system can be generated. The constructive proof can comprise instructions for using the subset of resources. A set of computer-executable instructions can be created from the constructive proof and executed on a host device. The computer-executable instructions can control a data output device according to the instructions of the constructive proof.

Abstract: Disclosed are embodiments of methods and systems for wireless data transmission by magnetic induction. In one embodiment, a network of magnetic induction units is provided. The units may be configured to transmit a data signal by modulation of a time-varying magnetic field. One or more units may also be configured to receive a data signal received from another magnetic induction unit. In one specific implementation, a network of underground magnetic induction units is provided, each having a sensor connected thereto. Each of the units, or a subset of the units, may be configured to transmit its sensed data to an adjacent or nearby unit, which, in turn, may retransmit the original data, along with additional appended data, to another adjacent unit. The network data may thereby be relayed in a multi-hop fashion until it reaches a desired destination.

Abstract: A semiconductor device (10, 100) comprising a Schottky charge transfer junction and a novel junction termination design. The device provides improved breakdown performance and reliability at reduced cost. The device may be fabricated by conventional technology on any semiconductor material, and is particularly suited for silicon carbide (SiC) and Group III-V nitrides (such as GaN). The junction termination design may be applied to PN charge transfer junctions (30) and combined with the Schottky charge transfer junctions (60) to form devices that comprise of one or more of such junctions. The overall result is significant improvement on-state conduction and switching characteristics.

Abstract: A method and apparatus are provided for improving a breakdown voltage of a semiconductor device. The method includes the steps of coupling an electrode of the silicon-carbide diode to a drift layer of the semiconductor device through a charge transfer junction, said drift layer being of a first doping type and providing a junction termination layer of a relatively constant thickness in direct contact with the drift layer of the semiconductor device and in direct contact with an outside edge of the charge transfer junction, said junction termination layer extending outwards from the outside edge of the charge transfer junction, said junction termination layer also being doped with a doping material of a second doping type in sufficient concentration to provide a charge depletion region adjacent the outside edge of the charge transfer junction when the charge transfer junction is reverse biased.

Abstract: A direct current to direct current boost or buck voltage converter in accordance with the invention includes a plurality of switching devices that effect voltage conversion and control current flow direction in the converter. The converter also includes a control circuit for comparing an output voltage of the converter with a reference voltage, where the control circuit produces a comparison signal based on that comparison. A resonant gate-drive circuit, also included in the converter and coupled with the control circuit and the plurality of switching devices, opens and closes the plurality of switches in response to the comparison signal to effect voltage conversion and control current flow direction.

Abstract: A system and method for detecting, measuring, and reporting a time derivate of a current signal (di/dt). A sensing element detects current from a load. The sensing element includes an inductor. The inductor is located in series with the load and includes associated parasitic resistance. A differential potential develops across the inductor and the parasitic resistance. The differential potential is amplified and converted to a single-ended value. The single-ended value is then fed to an analog to digital converter that provides an output representative of di/dt.

Abstract: A monolithically formed battery charger may be fabricated as an integral part of a multifunctional integrated circuit or as independent monolithically formed integrated circuit. The monolithically formed battery charger includes at least one step-down converter having a given duty ratio coupled to a battery-terminal interface that provides a stepped-down output voltage and current that may be used to charge a rechargeable battery. The step-down converter includes one or more cascaded monolithically-formed synchronous-buck regulators operating at a frequency of at least one megahertz. Each regulator may include a capacitor, inductor, controller, switch, and rectifier. When cascaded, the high-side output node of a preceding synchronous-buck regulator is connected to the switch in a successive synchronous-buck regulator.

Abstract: A logic state transition sensor circuit. The logic state transition sensor circuit detects and records transitions in voltage corresponding to a transition of a digital logic state (high to low; low to high). The logic state transition sensor circuit may include a sensing circuit containing sensing and amplification elements and a recording circuit containing recording elements. When a logic state transition occurs at an input of the sensing circuit, a positive logic pulse may be generated. Propagation of the logic pulse to the recording circuit causes a charge to be transferred to an output stage capacitor. Repeated logic state transitions cause similar incremental increases in the charge of the output stage capacitor. Charge transfer is governed by ratios of capacitors internal to the recording circuit and hence may be insensitive to process variation. The output stage capacitor may output a voltage representative of a number of logic state transitions sensed.

Abstract: A data comparator that operates on an input voltage signal and a reference voltage signal is disclosed. Internally, the comparator includes replicated circuitry to produce differential gain. Each set of replicated circuitry includes two gain stages for high amplification, high sampling rate, and for reducing kickback noise at the input voltage signal and the reference voltage signal. The comparator may further include self-biased CMOS inverters for cancellation of input offset error and a rail-to-rail regenerative output latch. The circuit can also include a comparator bias circuit that can improve the speed of the auto-zero operation.

Abstract: A direct current voltage boost converter includes a substantially static direct current voltage source coupled with an inductor. The converter also includes a step-up switch coupled with the inductor, and a capacitor coupled with, and between, electrical ground, and the inductor and the step-up switch via a switching device for controlling current flow direction. The converter further includes a single control circuit coupled with the step-up switch, the switching device and an output terminal of the boost converter, wherein the control circuit opens and closes the step-up switch and the switching device substantially out of phase with each other. This out of phase switching effects voltage conversion and regulation based, at least in part, on a desired output voltage and an output voltage present on the output terminal of the boost converter.

Abstract: A novel monolithic step-down dc-dc buck converter that uses two or more (“n”) parallel slices to achieve a high output current with a small filter capacitor is provided. Each of the n slices may be operated with a phase difference of 360°/n. Each of the converter slices may be based on a synchronous rectifier topology to avoid the excessive power losses introduced by the diode component of conventional step-down buck converters. Hysteretic control may be used (with or without pulse-width modulation and pulse-frequency modulation) to provide an internal gate-drive waveform without the need to provide a dedicated clock signal or oscillator circuit.

Abstract: A monolithically formed battery charger may be fabricated as an integral part of a multifunctional integrated circuit or as independent monolithically formed integrated circuit.

Abstract: A direct current voltage converter in accordance with the invention includes a substantially static direct current voltage source, an inductor; a current-control switch coupled with, and between, the voltage source and the inductor, a step-up switch coupled with the inductor, and a current sense device coupled in series with the step-up switch and electrical ground. The converter also includes a capacitor for storing converted voltage that is coupled with, and between, electrical ground, and the inductor and the step-up switch through a device for controlling current flow direction. The converter further includes a first control circuit, which opens and closes the current-control switch based, at least in part, on an electrical current conducted through the current sense device, and a second control circuit, which opens and closes the step-up switch based, at least in part, on a voltage potential across the electrical load.

Abstract: A direct current to direct current boost or buck voltage converter in accordance with the invention includes a plurality of switching devices that effect voltage conversion and control current flow direction in the converter. The converter also includes a control circuit for comparing an output voltage of the converter with a reference voltage, where the control circuit produces a comparison signal based on that comparison. A resonant gate-drive circuit, also included in the converter and coupled with the control circuit and the plurality of switching devices, opens and closes the plurality of switches in response to the comparison signal to effect voltage conversion and control current flow direction.

Abstract: A method and apparatus are provided for improving a breakdown voltage of a semiconductor device. The method includes the steps of coupling an electrode of the silicon-carbide diode to a drift layer of the semiconductor device through a charge transfer junction, said drift layer being of a first doping type and providing a junction termination layer of a relatively constant thickness in direct contact with the drift layer of the semiconductor device and in direct contact with an outside edge of the charge transfer junction, said junction termination layer extending outwards from the outside edge of the charge transfer junction, said junction termination layer also being doped with a doping material of a second doping type in sufficient concentration to provide a charge depletion region adjacent the outside edge of the charge transfer junction when the-charge transfer junction is reverse biased.

Abstract: A data comparator that operates on an input voltage signal and a reference voltage signal is disclosed. Internally, the comparator includes replicated circuitry to produce differential gain. Each set of replicated circuitry includes two gain stages for high amplification, high sampling rate, and for reducing kickback noise at the input voltage signal and the reference voltage signal. The comparator may further include self-biased CMOS inverters for cancellation of input offset error and a rail-to-rail regenerative output latch. The circuit can also include a comparator bias circuit that can improve the speed of the auto-zero operation.

Abstract: A system and method for detecting, measuring, and reporting a time derivate of a current signal (di/dt) is provided. A sensing element detects current from a load. The sensing element includes an inductor. The inductor is located in series with the load and includes associated parasitic resistance. A differential potential develops across the inductor and the parasitic resistance. The differential potential is amplified and converted to a single-ended value. The single-ended value is then fed to an analog to digital converter that provides an output representative of di/dt.