Abstract: A system and apparatus for detecting and locating an arc fault in a photovoltaic solar power array. A plurality of capacitors divide strings of photovoltaic cells into a series of magnetic loops. When an arc fault occurs within one of the loops, a time-varying magnetic field is produced, with flux lines emanating from the area enclosed by the loop. At least three magnetic field sensors arranged at locations in or around the solar power array detect the spectral signature of the arc fault, and send related data to a computer via a communication network. The computer analyzes the data from the sensors to determine the location of the arc fault.

Abstract: An electric leakage sensing apparatus includes a coupling capacitor having one end connected to a DC power supply, a pulse generator that supplies a pulse to the other end of the coupling capacitor, a voltage detector that detects a voltage at the coupling capacitor charged by the pulse, an electric leakage determination part that compares the voltage detected by the voltage detector to a threshold value, and makes a determination of existence or non-existence of an electric leakage of the DC power supply based on a comparison result, and a booster circuit that applies a boosted pulse voltage to the coupling capacitor. The pulse generator converts an output voltage of the booster circuit into the pulse voltage. The voltage detector includes an offset voltage generating circuit that generates an offset voltage.

Abstract: Wafer cassette systems and methods of using wafer cassette systems. A wafer cassette system can include a base and a probe card assembly. The base and the probe card assembly can each include complementary interlocking alignment elements. The alignment elements can constrain relative movement of the base and probe card assembly in directions parallel to a wafer receiving surface of the base, while permitting relative movement in a direction perpendicular to the receiving surface.

Abstract: Embodiments of this invention include a test and measurement instrument and associated methods for automatically setting frequency span in a spectrum analyzer. For example, starting with a high reference level, the power level can be automatically measured for each band. If a suitable minimum power is not found in one of the bands, the reference level can be automatically and iteratively decreased until the suitable minimum power is found, or until the most sensitive power level is reached. This assures enough sensitivity to correctly determine the signal power level and not make decisions based on noise. When power on any band is greater than the predefined noise criteria, then the band having the highest power level can be selected, and the center frequency and span for the band measuring the most power can be automatically set.

Abstract: In order not to deteriorate the detection properties of an ion current that monitors a combustion state even when a smolder leak is present in an ignition plug of an internal combustion engine, an ion current detector includes an ignition plug of an internal combustion engine, an ignition coil which supplies a high voltage to the ignition plug, a controller which sends an ignition command, a bias capacitor which supplies a bias voltage to the ignition coil, an ignition capacitor which is connected to a primary side winding of the ignition coil, a DC power supply which charges the ignition capacitor and the bias capacitor, a current detecting unit which detects a current flowing through the ignition plug, an ion current detecting unit which detects an ion current from the current detected by the current detecting unit, and a Zener diode which restricts a charging voltage of the bias capacitor.

Abstract: A method and system for testing a read transducer are described. The read transducer includes a read sensor fabricated on a wafer. A system includes a test structure that resides on the wafer. The test structure includes a test device and a heater. The test device corresponds to the read sensor. The heater is in proximity to the test device and is configured to heat the test device substantially without heating the read sensor. Thus, the test structure allows for on-wafer testing of the test device at a plurality of temperatures above an ambient temperature.

Abstract: A micromachined magnetic field sensor is disclosed. The micromachined magnetic field comprises a substrate; a drive subsystem, the drive subsystem comprises a plurality of beams, and at least one anchor connected to the substrate; a mechanism for providing an electrical current through the drive subsystem along a first axis; and Lorentz force acting on the drive subsystem along a second axis in response to a magnetic field along a third axis. The micromachined magnetic field sensor also includes a sense subsystem, the sense subsystem includes a plurality of beams, and at least one anchor connected to the substrate; wherein a portion of the sense subsystem moves along a fourth axis; a coupling spring between the drive subsystem and the sense subsystem which causes motion of the sense subsystem in response to the magnetic field; and a position transducer to detect the motion of the sense subsystem.

Abstract: A clock-detecting circuit, containing at least a microprocessor, a clock circuit, and a zero-cross detecting circuit. The clock circuit is connected to the microprocessor. The input end of the zero-cross detecting circuit is connected to the utility power AC input. The output end of the zero-cross detecting circuit is connected to the input end of the microprocessor. The zero-cross detecting circuit operates to detect zero crossing points of the utility power AC input. The microprocessor operates to count the number of oscillation periods of the clock circuit in a time interval between two adjacent zero crossing points of the utility power AC input and to detect clock precision of the microprocessor according to the counted number. The circuit according to the invention features simple structure and low production cost, and is reliable and easy to be implemented.

Abstract: A circuit arrangement includes a load transistor and a sense transistor. The first load terminal of the load transistor is coupled to the first load terminal of the sense transistor. A measurement circuit comprising a current source configured to provide a calibration current, the measurement circuit configured to measure a first voltage between the first load terminal and the second load terminal of the sense transistor in the on-state of the sense transistor, to determine a resistance of the sense transistor based on the calibration current and the first voltage, to measure a second voltage between the first load terminal and the second load terminal of the load transistor in the on-state of the load transistor, and to determine a load current through the load transistor based on the resistance of the sense transistor and the second voltage.

Abstract: A circuit for measuring current drawn by a self-powered electronic protection device. The circuit monitors current in a polyphase alternating current (AC) power source by measuring current in a rectified secondary winding of a current transformer coupled to a phase current of the power source. The measurement circuit includes a measurement burden connected between the cathode of the current transformer rectifier and a switch. Closing the switch references the voltage drop across the measurement burden to a reference potential. A controller closes the switch while receiving measurements of the voltage drop. Because the voltage drop is referenced to a reference potential, it can be analyzed in a controller to detect a fault condition without being conditioned with an inverting amplifier or a difference amplifier.

Abstract: A system and method for improved voltage contrast inspection is disclosed. In one embodiment the temporal response to voltage contrast is considered to find an optimal acquisition time. In another embodiment, multiple optimal acquisition times are identified. The identified acquisition times are used in voltage contrast inspection of semiconductor fabrication, and are well-suited to SOI technology.

Abstract: A method of probe card partitioning for testing an integrated circuit die includes providing a first probe card partition layout having a first number of distinct sections. Each distinct section uses a distinct probe card for testing. The first probe card partition layout is repartitioned into a second probe card partition layout having a second number of distinct sections. The second number is less than the first number.

Abstract: A calibration method for adjusting an offset voltage of a unit is proposed. The unit, capable of operating in a calibration mode or a normal mode, includes a first input terminal, a second input terminal and an output terminal. The calibration method includes: operating the unit in a calibration mode; providing a programmable voltage to the first input terminal; providing a constant voltage to the second input terminal; adjusting the programmable voltage monotonously when an output status of the output terminal is not changed; latching the programmable voltage when the output status toggles; and operating the unit in a normal mode after the output status toggles.

Abstract: Core loss in an inductor is measured with reduced sensitivity to phase measurement error by connecting a reactive component to resonate with the inductor and thus cancel a portion of the reactive voltage on the inductor; reducing the phase difference between the inductor voltage and current and making the observed power more resistive. The reactive component may be a capacitor for sinusoidal excitation or an inductance such as an air core transformer for arbitrary excitation.

Abstract: A digital multimeter includes a body having a function selector and a first coupler and includes a head having a display and a second coupler. The function selector selects a parameter to be measured, and the display displays a measurement corresponding to the parameter to be measured. The first and second couplers are engaged in a first arrangement joining the body and the head, and the first and second couplers are disengaged in a second arrangement separating the body and the head.

Abstract: A method and apparatus use a plurality of first region values to calculate a second region value, each of the plurality of first region values reflecting sensor element activity in a corresponding region of an input module, the second region value reflecting sensor element activity of a group of the corresponding regions. The method and apparatus determine that the input object is present relative to the group of the corresponding regions if the second region value meets or exceeds a threshold presence value.

Abstract: The present disclosure generally relates to an evanescent microwave microscopy probe and methods for making and using the same. Some embodiments relate to a probe which is constructed of silver. Other embodiments relate to a method of measuring an unknown property a target material, comprising moving the probe away from the target material, taking a first measurement, moving the probe such that it touches the target material, taking a second measurement, and comparing the first and second measurements in order to measure the unknown property.

Abstract: A system and method for identifying opens among parallel connections on a circuit assembly such as a printed circuit board (PCB). In a learn phase performed on a known good circuit assembly, a group of parallel connected pins are excited with a first signal. A second signal, out-of-phase with the first signal, is applied to a second group of pins associated with the component. The amplitude and/or the phase of the second signal and the number and/or specific pins in the second group of pins are selected so that first and second signals coupled to a detector plate proximal to the component substantially offset. During a manufacturing test, signals of comparable amplitude and phase are applied to like pins on a like component of a circuit assembly under test. If the response signal coupled to a like detector plate is below a threshold, it is determined that each pin in the group of parallel connected pins is connected.

Abstract: A salinity determining system for determining a salinity of water in a hydrocarbon emulsion of oil and water. The salinity determining system includes an antenna element in contact with the hydrocarbon emulsion and a switch coupled to the antenna element. The salinity determining system includes a first analyzer device configured to be coupled to the antenna element via the switch. The first analyzer device is associated with a first coincidence function based on first measured electrical parameters of transmitted radio-frequency (RF) energy. The salinity determining system also includes a second analyzer device configured to be coupled to the antenna element via the switch.

Abstract: A stiffener for a probe card assembly can include decoupling mechanisms disposed within radial arms of the stiffener. The decoupling mechanisms can be compliant in a direction along a radial direction of said radial arm and rigid in a direction perpendicular to said radial arm. The decoupling mechanisms can decouple the stiffener from thermally induced differential radial contraction and expansion of the stiffener relative to the cardholder to which the stiffener is mounted. This can reduce thermally-induced vertical translation of the probe card assembly.