Abstract: The voltage variation detection circuit includes: a threshold voltage generation circuit arranged to generate a threshold voltage; a comparator arranged to compare a variation detection-target voltage and the threshold voltage to each other; and a controller arranged to control the threshold voltage generation circuit based on output of the comparator. Repeated are operations of: decreasing the threshold voltage stepwise; when the variation detection-target voltage has come to the threshold voltage or more, first increasing the threshold voltage by specified steps and then again decreasing the threshold voltage stepwise; and when the variation detection-target voltage has come to the threshold voltage or more, increasing the threshold voltage by specified steps. The controller detects a variation of the variation detection-target voltage based on control results at time points when the variation detection-target voltage comes to the threshold voltage or more.

Abstract: A detection circuit of an electronic device includes a resistance detecting circuit and a voltage supplying circuit, wherein the detecting circuit is coupled to an input circuit which is coupled to the electronic device and comprises a plurality of resistors respectively coupled to a plurality of switches, wherein the resistance detecting circuit is arranged to detect whether the input circuit has a resistance variation and generate a detecting signal indicative of the resistance variation; and the voltage supplying circuit is coupled to the resistance detecting circuit to supply a first voltage signal, wherein the voltage supplying circuit receives the detecting signal, and selectively switches the first voltage signal to a second voltage signal according to the detecting signal; wherein the resistance detecting circuit determines whether at least one of the plurality of switches is closed according to the second voltage signal.

Abstract: A temperature measurement system is disclosed. In accordance with some embodiments of the present disclosure, a temperature measurement system may comprise a resistor, a thermistor, a resistance-to-current converter configured to generate a current signal based on a resistance, an analog-to-digital converter (ADC) configured to receive a first current signal based on the resistor, convert the first current signal into a first digital signal, receive a second current signal based on the thermistor, and convert the second current signal into a second digital signal, and a calculation stage communicatively coupled to an ADC output and configured to determine a first digital value based on the first digital signal, determine a second digital value based on the second digital signal, calculate a resistance ratio based on the first digital value and the second digital value, and determine a temperature output value based on the resistance ratio.

Abstract: A voltage stability monitoring apparatus monitors the voltage stability of a transmission corridor through which power flows between different parts of a power system. The apparatus monitors an equivalent load impedance at an interface between the transmission corridor and a part of the power system designated as generating the power. This equivalent load impedance at the interface comprises a ratio of a voltage phasor at the interface to a current phasor at the interface. The apparatus tracks a Thevenin equivalent voltage and impedance of the designated part by separately updating that voltage and impedance. Notably, the apparatus updates the Thevenin equivalent voltage to reflect the magnitude of any changes in the voltage phasor that are associated with large variations in the magnitude of the equivalent load impedance at the interface. The apparatus computes an index indicating the voltage stability as a function of this tracked Thevenin equivalent voltage and impedance.

Abstract: A system for providing power to a powered device over a communication cable has a cable resistance measuring mechanism that determines values of response signals detected in response to supplying each of at least three reference signals over the communication cable, and determines the resistance of a pair of wires in the cable based on these values. The cable resistance measuring mechanism may be configured for determining resistance of an Ethernet cable that delivers power to the powered device in a Power over Ethernet system.

Abstract: A circuit for detecting variation of a resistance value of a resistor with respect to a reference value includes a first resistor; a second resistor; a first current source circuit for supplying current to the first resistor; a second current source circuit for supplying current to the second resistor; a voltage comparator circuit for comparing a voltage across the first resistor and a voltage across the second resistor; and a control circuit for digitally adjusting the supply current of at least one of the first or second current source circuit. A ratio of resistance values of the first and second resistors can be obtained from an adjustment value from the control circuit and result of comparison from the voltage comparator circuit.

Abstract: A method and a device for monitoring at least one output stage for an inductive load using a current regulator and an analysis device are described. A short circuit to a power supply or to ground is detected by comparing at least one current value in a switching phase of the at least one output stage with at least one current value in a free-wheeling phase of the at least one output stage.

Abstract: Disclosed is a method of evaluating a ground reinforcement effect using 4-D electrical resistivity monitoring, wherein the ground reinforcement is made up on an underground cavity through cement mortar grouting, the method including: (a) installing a survey line for measuring electrical resistivity in a ground reinforcement zone; (b) measuring the electrical resistivity of the ground reinforcement zone through the survey line before grouting mortar, and imaging three-dimensional electrical resistivity distribution in the ground reinforcement zone by applying a three-dimensional electrical resistivity inversion to the measured results; (c) measuring the electrical resistivity of the ground reinforcement zone through the survey line while or after grouting the mortar, and imaging the three-dimensional electrical resistivity distribution in the ground reinforcement zone by applying the three-dimensional electrical resistivity inversion to the measured results; and (d) calculating a change ratio of the electrical

Abstract: There is provided an insulation resistance detecting apparatus that accurately calculates an insulation resistance value in real time.

Abstract: A system for providing power to a powered device over a communication cable has a cable resistance measuring mechanism that determines values of response signals detected in response to supplying each of at least three reference signals over the communication cable, and determines the resistance of a pair of wires in the cable based on these values. The cable resistance measuring mechanism may be configured for determining resistance of an Ethernet cable that delivers power to the powered device in a Power over Ethernet system.

Abstract: The present invention employs identically sized mirror transistors arrange in groups that may be preferentially addressed and activated to determine the value of a resistor. Known current are directed through the resistor, and the voltage developed is measured by comparing against a reference voltage. The current is increased or decreased by the least significant value until the voltage across the resistor matches the reference voltage. A successive approximation or other known technique may be used instead. A reference current is developed that temperature stable and that is trimmed when manufactured to reduce process effects. The reference voltage may be constructed to be independent form a local power source so that the system is relatively independent of process, voltage and temperature, PVT.

Abstract: There is provided an insulation resistance detecting apparatus that accurately calculates an insulation resistance value in real time.

Abstract: A test system includes a circuit assembly having an IC and an external circuit. The IC includes test circuitry used to observe data indicative of target resistances in the external circuit. The test system evaluates the data to determine target resistance values. A first embodiment measures two output voltages responsive to a time varying reference voltage. The two output voltages can be used to determine resistance values in the external circuit. A second embodiment enables logic contention on the IC, controllably fixes a pull-down element on the IC, and controllably sweeps a pull-up element on the IC until the voltage at a node between the pull-down and pull-up elements and coupled to an external circuit exceeds a reference voltage.

Abstract: A method for analyzing skin response waveform information obtained by measuring skin impedance with a voltage of a predetermined frequency. A current value at the start of polarization caused by the application of the voltage is determined, followed by determining a current value after a predetermined amount of time from the start of the polarization. A current value after termination of the polarization (value NT) is then determined and the difference between the current value at the start of the polarization and after the predetermined amount of time from the start of the polarization (value A) is determined. The difference between the current value after the predetermined amount of time from the start of the polarization and the value NT (value B) is determined, followed by analyzing the skin response waveform information using the ratios A/B, B/A and the value NT.

Abstract: A device and method for measuring an impedance between first and second nodes in an electrical circuit without removing components includes at least one current source to provide first and second currents or current signals of known values. First and second probes contact the respective first and second nodes to apply the first and second currents. A third common probe contacts the circuit at a common node that experiences the same current flow as between the first and second nodes. At least one voltage meter measures voltages corresponding to the first and second currents. A processor calculates the impedance based on the known values of the currents, and the measured values of the voltages.

Abstract: A system for measuring differences in a physical variable, such as temperature or voltage, by utilizing predictable behavior in the relative time drift of offset curves for various circuit elements, including, for example, two sensors coupled to a difference signal amplifier, an ambient condition amplifier, and an analog to digital converter. In an initial calibration mode, the system records several offset curves, stored in memory, correlating ambient condition measurements to offset measurements acquired from the ambient condition amplifier and the difference signal amplifier. Offset curves recorded in the initial calibration mode, correlating ambient condition measurements to measurements from the difference signal amplifier, include one curve recorded with both inputs of the difference signal amplifier held at equal potential and another curve recorded with both sensors held at the same value of the physical variable, over a given ambient condition range.

Abstract: A ratio meter and apparatus for measuring electrical components with high stability and no effect on the circuit under test. Two input signals are switched by a switching means and the inputs to two measuring means are measured while keeping the switches in a first state and a second state to find the ratio of the measurements. The ratio to be measured, which is related to the above-mentioned input signals, and which forms a bilinear equation with the two ratios, one each obtained under the first and second state, are obtained from said ratios. Accurate calibration is performed and measurement of electrical and electronic components with high stability is accomplished by connecting a front-end circuit with the ratio meter.

Abstract: A system and method for measuring the alternating current series resistance of a conductor when transporting large currents on the order of several thousand amperes. The system comprises a current sensor, a current/voltage converter, a voltage divider, a voltage sensor, a null indicator, and a voltage meter. The alternating current series resistance is measured by measuring a real component of a voltage drop over a predetermined length of the conductor, deriving a measurement current from the conductor, converting the measurement current into a measurement voltage, withdrawing an adjustable portion of voltage from the measurement voltage, comparing the adjustable portion of voltage with the voltage drop, adjusting the adjustable portion of voltage to balance the voltage drop, measuring the alternating current, and determining the resistance of the conductor as a function of the value of the adjustable portion of voltage that balances the voltage drop and the measured alternating current.

Abstract: A device for the comparison of two resistors is based upon analog information carried by currents. The device includes a measurement circuit for extracting the currents from the two resistors to be compared, and copies the currents to a parallel analog-digital converter that carries out the division of the extracted currents. The device converts the ratio of the extracted currents into a digital code that is the image of the ratio of the two resistors. The ratio is constantly re-updated as a function of environmental parameters of the circuit, such as the operating temperature. Also disclosed is a system for correcting the value of integrated compensated resistors. The system implements a device of this kind that does not use a reference voltage generator.

Abstract: Disclosed is a current sensing system for measuring the current flowing through a current sensing resistance. The system has a calibration resistance coupled to the current sensing resistance and a pair of input resistances each having a first end coupled to one of the ends of the current sensing resistance and a second end coupled to one of the ends of the calibration resistance. A voltage is created across the calibration resistance and the calibration resistance is set at a predetermined level to compensate for the current sensing resistance deviating from a reference value. The voltage is filtered and amplified to produce an output representative of the measured current.

Abstract: A method for sorting integrated circuit (IC) devices of the type having a substantially unique identification (ID) code, such as a fuse ID, includes automatically reading the ID code of each of the IC devices and sorting the IC devices in accordance with their automatically read ID codes.

Abstract: An inventive method for sorting integrated circuit (IC) devices of the type having a substantially unique identification (ID) code, such as a fuse ID, includes automatically reading the ID code of each of the IC devices, and sorting the IC devices in accordance with their automatically read ID codes. The inventive method can be used in conjunction with an IC manufacturing process that includes providing semiconductor wafers, fabricating the IC's on each of the wafers, causing each of the IC's to store its ID code, separating each of the IC's from its wafer to form IC dice, assembling the IC dice into IC devices, and testing the IC devices.

Abstract: An inventive method for sorting integrated circuit (IC) devices of the type having a substantially unique identification (ID) code, such as a fuse ID, includes automatically reading the ID code of each of the IC devices, and sorting the IC devices in accordance with their automatically read ID codes. The inventive method can be used in conjunction with an IC manufacturing process that includes providing semiconductor wafers, fabricating the IC's on each of the wafers, causing each of the IC's to store its ID code, separating each of the IC's from its wafer to form IC dice, assembling the IC dice into IC devices, and testing the IC devices.

Abstract: A contact resistance check circuit and method for verifying that a sufficient electrical connection is established between a source and a sense lead of a Kelvin connection. The circuit includes a microprocessor for driving a transformer that is connected to the source/sense probe (i.e., contact resistance) with an input pulse. The input pulse is altered in relation to the magnitude of the contact resistance to produce a check pulse. A comparator is used to compare the check pulse with a threshold voltage and for generating a fault indication signal. A flip flop then stores the fault indication signal so that the fault indication signal may be monitored by the microprocessor.

Abstract: A process for controlling the weldability of a sheet (1) of the composite metal sheet type having a layer (7) which is interposed between two metal facing sheets (3,5) and comprises a polymer (8) having a filler of conductive particles (9). This process comprises measuring by means of a signal of given frequency f applied to two electrodes (11,13) disposed in facing relation to each other, each electrode being in contact with a corresponding metal facing sheet (3,5), the voltage/current phaseshift .phi. due to the resistive and capacitive properties of the composite sheet (1). The response of the composite sheet (1) to this signal corresponds to that of an equivalent parallel RC circuit. Thereafter, the mass fraction of the conductive particles (9) is calculated from the value of .phi.. By comparing the determined mass fraction with prefixed thresholds, the weldability and the vibration-damping capacity of the composite sheet (1) are evaluated.

Abstract: A relative volume fraction probe particularly for use in a multiphase fluid system includes two parallel conductive paths defining therebetween a sample zone within the system. A generating unit generates time varying electrical signals which are inserted into one of the two parallel conductive paths. A time domain reflectometer receives the time varying electrical signals returned by the second of the two parallel conductive paths and, responsive thereto, outputs a curve of impedance versus distance. An analysis unit then calculates the area under the curve, subtracts the calculated area from an area produced when the sample zone consists entirely of material of a first fluid phase, and divides this calculated difference by the difference between an area produced when the sample zone consists entirely of material of the first fluid phase and an area produced when the sample zone consists entirely of material of a second fluid phase. The result is the volume fraction.

Abstract: An impedance probe circuit and method presents a balanced load to a DC or RF voltage source and to two voltage measurement nodes. The impedance probe circuit is accurate for measurement of an impedance device X which has a range always less than the value of a characteristic impedance C. A source terminal is coupled to a voltage source having a series impedance C. A test resistor T is connected between the source terminal and one terminal X1 the unknown impedance. A reference resistor R is connected between the source terminal and the other terminal X2 of the unknown impedance. The parallel combination of the test resistor T and the reference resistor R has an impedance substantially equal to C/3. A third impedance of value C/3 is connected to the node X1 and to a first voltage measurement terminal. A fourth impedance of value C/3 is connected to the node X2 and to a second voltage measurement terminal.

Abstract: Methods of measuring, adjusting and uniformalizing a sectional area ratio of a metal-covered electric wire, a method of cleaning an electric wire, a method of manufacturing a metal-covered electric wire, an apparatus for measuring a sectional area ratio of a metal-covered electric wire, and an apparatus for electropolishing a metal-covered electric wire.Electric resistance values of first and second materials are previously stored respectively so that a sectional area ratio of a metal-covered electric wire is calculated on the basis of the as-stored values and an actually measured electric resistance value of the metal-covered electric wire. Measurement and uniformalization of a sectional area ratio of a metal-covered electric wire and cleaning of an electric wire are carried out by dissolving surface layer parts of the electric wires by electropolishing.

Abstract: Integrated voltage divider comprising partial resistors (R1 ,R2) formed of paths of polycrystalline semiconductor material applied over a dielectric layer (4) on a semiconductor substrate (5). Under the paths, each forming a partial resistor (R1,R2) in the semiconductor substrate (5), a well (6 and 7 respectively) is formed having a conductivity type opposite to the conductivity type of the semiconductor substrate (5). The total surfaces of the paths forming the partial resistors (R1,R2) are dimensioned so that their ratio equals the inverse ratio of the resistor values of the two partial resistors (R1 ,R2).

Abstract: In a voltage drop detecting circuit, when voltage Vcc being monitored is at a steady-state value, reference voltage B is classified by divided voltages Va to Vc from detection voltage generation circuit group for classification of reference voltage. In accordance with the result of that classification, one of the divided voltages Va to Vc from detection voltage generation circuit group for detection of a drop in the voltage being monitored is selected as detection voltage A. Since the resistance ratio can be expressed fairly correctly in ICs, the circuit structure of the voltage drop detecting circuit is capable of reducing the apparent range of variation of reference voltage B, whereby the precision of detection is improved.

Abstract: A method and apparatus for determining the resistance of the coils and commutator connections in an armature of an electric motor wherein a current is generated between a first commutator segment and a commutator segment located at least three segments beyond said first segment, a first voltage is measured across the first commutator segment and an adjacent second commutator segment, a second voltage is measured across the second commutator segment and an adjacent third commutator segment, and a third voltage is measured across a pair of commutator segments which are adjacent to the first commutator segment. After the three voltages are measured, the current is disconnected, and a voltage is generated across two commutator segments spaced at least three segments beyond the first segment. The generated voltage is adjusted so that the voltage measured across the second and third commutator segments equals the previous measurement, and the voltages are remeasured.

Abstract: A current in a circuit is measured without breaking the circuit. A relatively low resistance element in the circuit such as a component lead is chosen. A current is forced through the element and the voltage drop measured. Another current is forced through the element and the voltage drop measured. The values of these currents and voltages are used to determine the original current in the circuit.

Abstract: An apparatus and method for determining a characteristic of a resistor and/or an environment occurring as a voltage across a measuring resistor (e.g., a voltage across a temperature-dependent resistor) by comparing it with a reference value that occurs as a voltage across a reference resistor (e.g., a voltage across a temperature-stabilized reference resistor) to determine, for example, temperature. A total of four voltages are measured. That is, positive and negative currents are passed through the measuring resistor and the resulting first and second voltages across the measuring resistor are detected. Positive and negative currents then are passed through the reference resistor and the resulting third and fourth voltages across the reference resistor are detected. The difference between the first and second voltage and the third and fourth voltages is determined to eliminate the effect of thermo-electric voltages in the lines to the resistors and the lines of the contact terminals in the switches.

Abstract: Disclosed is a method and apparatus for determining weld and coil resistances of a commutator type electric motor armature. The method comprises the steps of determining a resistance ratio for a pair of coils and then determining the weld resistance across a commutator bar and coil connection based upon the resistance ratio.

Abstract: The present invention includes a dielectric sensor which provides at least two signals corresponding to the sensed dielectric of a petroleum stream. A temperature sensor also senses the temperature of the petroleum stream and provides a corresponding temperature signal. Crossplot data arrange the two parameters associated with the petroleum stream dielectric is stored in a memory. The memory is accessed using signals from the dielectric sensor and the temperature sensor to select data from the memory. An output circuit provides a water cut signal in accordance with the selected data.

Abstract: A liquid mixing ratio detecting apparatus is designed so that an oscillation voltage generated by an oscillation unit is applied to one of a differentiating circuit and an integrating circuit, which is constituted by a combination of a capacitor composed of a pair of opposite electrodes for detecting a mixing ratio of a mixed liquid and a resistor, and a mixing ratio detecting unit produces a signal relating to an inclination rate of one of a differential waveform signal and an integration waveform signal, which is generated by one of the differentiating circuit and the integrating circuit, respectively, thereby obtaining a signal representing the mixing ratio of the mixed liquid on the basis of the produced signal relating to the inclination rate of the waveform signal.

Abstract: The arrangement serves to process sensor signals furnished by a sensor which when fed with a supply signal in response to the action of a physical measured quantity. The sensor generates a measuring effect representing the dependence of an electrical characteristic quantity on the physical measured quantity. The arrangement also includes a signal processing circuit which operates by the principle of quantized charge transport by means of switch-capacitor structures. The signal processing circuit establishes a charge balance by opposite integration of measuring charge packets dependent on the measuring effect and compensation charge packets independent of the measuring effect and furnishes an analog output signal corresponding to the integration result. The analog output signal also provides a feedback input to the sensor. By this feedback the analog output signal is regulated so that it is proportional to the measurement result.

Abstract: A position determining device for an adjustment device including two continuous potentiometers having sliders movable to respective positions determininng respective resistance values of the potentiometers, the sliders being coupled with the adjustment drive so that the respective resistance values determined by the positions of the sliders correspond to a set position of the adjustment drive, a device for driving each of the sliders with a transmission ratio different from one another so that the potentiometers have a resistance value different from one another for a given set position of the adjustment drive, and a device for establishing a differential value from the different resistance values as a measure of the set position of the adjustment drive.

Abstract: A position detecting apparatus electrically detects the present position of a moving body reciprocated within a movable region. The apparatus comprises a resistance section continuously disposed by a predetermined length along the reciprocating direction within a detecting region corresponding to the movable region on a substrate composed of an insulator. A plurality of region discriminating patterns are formed by combining a conductive section discontinuously disposed by a predetermined length along the reciprocating direction within the detecting region on the substrate, and an insulating section having no conductor. An electric brush is provided which is connected to the moving body and reciprocated within the detecting region in a state in which the brush slidably contacts the resistance section and the plurality of region discriminating pattern section.