Abstract: Two centerlines each of which goes through the center of a surface and is parallel to one of the coordinate axes are considered for each surface constituting a cell. If one of the centerlines intersects a boundary, a line which goes through the intersection and is orthogonal to the centerline is approximated as a new boundary. If a boundary intersects with each of the two centerlines, an orthogonal line expressed by each of two lines which is obtained by crossing each of the two centerlines parallel to each different coordinate axis and a boundary is approximated as a new boundary. Thus, the new boundary is expressed by each part of these orthogonal lines toward the centerline from their intersection.

Abstract: A control circuit of a DC fan motor for start with high voltage and high rotational speed with low voltage at least includes an input unit, an output unit, a control unit and a comparator. The input unit is connected to the comparison unit and the control unit for the power being inputted to operate the control circuit. The output unit has motor coil sets to be connected to the control unit such that the output unit can be driven by way of being controlled with the control unit. The comparison unit is connected to the control unit to control output current of the control unit. Hence, while the motor starts in a condition of being high voltage, the control element can prevent from being burned out due to excessively large current. Further, the motor fan can maintain a high constant rotational speed with low voltage output to enhance capability of heat dissipation and power saving.

Abstract: A signal processing unit for a pressure switch or the like, comprising a sensor element, such as a strain gauge bridge, to supply an analog electrical signal that corresponds to a pressure; a signal processing unit which is connected downstream of the sensor element to amplify and digitize the analog signal; and a control unit for electrical switches which is connected downstream of the signal processing unit to switch external loads or the like. According to the invention, the signal processing unit comprises a chopper amplifier, which switches or balances the polarity of the analog electrical signal present at its input and supplied by the sensor element, and the amplified analog electrical or digitized signal present at its output, at the same clock rate.

Abstract: A method for a modified binary search includes steps of: selecting a parameter having a distribution of values, selecting a probability density function representative of the distribution of values of the selected parameter, defining a substantially equal probability weighted binary test interval from the probability density function for each of a selected number of test intervals over a selected test range, translating the weighted binary test intervals to obtain a highest resolution at a target point of the selected parameter, and skewing the translated and weighted binary test intervals by a selected scaling function to generate a modified binary test interval for each of the selected number of test intervals over the selected test range.

Abstract: A method and apparatus for calibrating a current source to a reference current through the use of 1-bit current comparisons. A temporary current source is first calibrated to the reference current, which allows an input offset current generated by the current comparator to be memorized. The current to be calibrated is then fine-tuned to the temporary current within specified limits, which effectively cancels comparison error that is generated by the input offset current.

Abstract: According to at least one embodiment, a method comprises measuring drive current of a reference memory cell of a circuit, and determining, based on the measured drive current of the reference memory cell, a drive current to be supplied to a calibration memory cell of the circuit to mimic a defective memory cell. The method further comprises supplying the determined drive current to the calibration memory cell, and using the calibration memory cell to determine strength of a weak write to be utilized by a weak write test for detecting defective memory cells.

Abstract: The present invention, in one embodiment, is a method for operating an electronic electric meter having current and voltage sensors configured to generate measurements of current and voltage, respectively; a microcomputer coupled to the current and voltage sensors and having on-chip masked read only memory (ROM); and a nonvolatile, alterable memory coupled to the microcomputer. The method includes steps of: storing vectors pointing to program portions of the ROM in the non-volatile memory; and using the stored vectors to operate the microcomputer to execute the program portions stored in the ROM to control operation of the meter.

Abstract: The invention provides a method for magnetic imaging of an object. The method comprises monitoring a magnetic field of sources in the object at a plurality of magnetic detectors to obtain a corresponding plurality of sensor outputs, monitoring a position of the object while monitoring the magnetic field of the sources, modeling the magnetic field of the sources in the object as a gradient of a scalar potential, the scalar potential comprising a sum of spherical harmonic functions each multiplied by a corresponding coefficient, and, compensating for the position of the object by applying a transformation to the plurality of sensor outputs, the transformation including, at least in part, a spherical harmonic translation transformation.

Abstract: A frequency harmonic identifier for detecting series arcs on a power line includes a frequency analyzer for providing the harmonic content of a sensed current signal and a decision logic for comparing a tested signal to at least one reference signal band. The reference signal band or bands may represent a variety of common loads and if the tested signal does not match any of the sets of reference signal bands, then the logic determines the tested signal to be a series arc signal. The frequency harmonic identifier may be provided within a circuit interrupter and may issue a trip signal if the tested signal is determined to be a series arc signal. Also disclosed is a method for detecting series arcs, and a storage medium having instructions for causing a computer to implement the method.

Abstract: A method, apparatus and computer program product are provided for implementing power system performance. Power supply system data are processed and a power path in a power supply system having a predefined component failure mode is identified for placement of a fuse. Transient and steady state current levels are determined for each identified power path. A fuse size is selected within an identified fuse size range based upon the determined transient and steady state current levels. A selected fuse energy rating is lower than an energy rating of the solid-state devices in the identified power path.

Abstract: Disclosed herein is a method and system for calibrating line drive currents in systems that generate data signals by varying line drive currents and that interpret the data signals by comparing them to one or more reference voltages. The calibration includes varying the line drive current at a transmitting component. At different line drive currents, a receiver reference voltage is varied while the transmitting component transmits data to a receiving component. At each line drive current, the system records the highest and lowest receiver reference voltages at which data errors do not occur. The system then examines the recorded high and low receiver reference voltages to determine a desirable line drive current.

Abstract: A signal compensation circuit of a bus is disclosed in the present invention, wherein the amplitude of a surge is obtained by inputting a test pattern into the bus and comparing a reference voltage and a peak-value signal filtered out from the bus. For continual correction of the damping resistance, the test pattern can be inputted into the bus repeatedly to optimize the effect of the compensation. Then, a proper damping resistor is selected and connected to the bus in series to absorb the energy of the surge. The signal compensation circuit is embedded in the chip, such as in the south bridge.

Abstract: A voltage detection unit generates a detection voltage signal representative of a potential difference caused by a current to be detected. A reference current generation unit generates a first reference current and a second reference current having a linear relationship therebetween. In response to the detection voltage signal and the first reference current, a transfer unit determines a first operation voltage. Furthermore, the transfer unit determines a second operation voltage and a transfer current in response to the first operation voltage and the second reference current. The second operation voltage is substantially equal to the first operation voltage. A detection current signal having a linear relationship with the current to be detected is generated through subtracting at least the second reference current from the transfer current.

Abstract: In a method for optimizing an ion detector a control voltage, such as in a mass spectrometry system, an array of mass scan data is acquired. Based on the size of the largest peak in the array or part of the array, a determination is made as to whether the current detector gain should be changed to a new detector gain. If the current detector gain should be changed, the control voltage for the subsequent mass scan is adjusted to a new control voltage corresponding to the new detector gain. The data are scaled based on the current detector gain. In another method, a gain versus control voltage curve is generated for calibration. These methods may be implemented by hardware, software, analog or digital circuitry, and/or computer-readable or signal-bearing media.

Abstract: The present invention provides a method for verifying a design of a circuit board that has a wiring layer connecting components to be mounted, a power layer, and an insulating layer formed between the wiring layer and the power layer. According to this method, detection of chippings in the power layer is performed. The chipping is, for example, a gap, a slot, or a slit, and corresponds to one wiring layer and interrupts a region in which the wiring layer and the power layer are opposed to each other. When chippings are detected, a common-mode voltage expected to be caused owing to each of the chippings is computed. Subsequently, the position of the chipping and the value of the common-mode voltage caused owing to the chipping are outputted. Thus, the priorities of the chippings, to which countermeasure for suppressing radiation of electromagnetic waves should be applied, can easily be decided.

Abstract: A low voltage swing bus analysis method using a static timing analysis (STA) tool, which provides simple and accurate timing analysis verification. The low voltage swing bus analysis method is used in a static timing analysis (STA) tool. The STA tool receives a design file which executes the timing verification program then extracts the timing model for each cell, present in a design file during execution of the timing verification program, and calculates a timing for each node. The STA tool extracts a timing model for a sense amplifying flip flop, among cells present in the design file during execution of the timing verification program, from execution of a subroutine and calculating a timing for each node connected to the sense amplifying flip flop. The STA tool outputs the calculated timings.

Abstract: An on-line sensing system and method for monitoring in real-time thermal-oxidative breakdown, water contamination, and/or fuel dilution conditions in operational engine lubricating oils. The method of the invention includes an electrochemical impedance analysis technique specific to the particular oil to be monitored. Sensing devices having of at least two electrodes are configured for direct installation in an existing access port, or drain port, of a lubricating oil reservoir. An AC voltage waveform is applied to the sensing device (preferably less than 100 Hz) to produce voltage and current responses between the appropriate electrodes contacting the oil. The magnitude impedance |Z| and phase angle components of the complex impedance are used to characterize the quality and/or condition of the engine oil under test. The system also provides an electrical indication indicative of the percentage remaining useful life of the oil.

Abstract: A storage battery includes a battery housing and a plurality of electrochemical cells in the battery housing electrically connected to terminals of the battery. A battery test module is mounted to the battery housing and electrically coupled to the terminals through Kelvin connections. A display or other output is configured to output battery condition information from the battery test module. Battery post extensions couple the battery test module to terminals of the battery.

Abstract: An electronic system for the continuous monitoring of voltage charge within the electrical system of a motor vehicle having an electrical generation source and a secondary electrochemical cell or battery. The system comprises a programmable in-vehicle monitor having a flashing LED indicator that alerts the vehicle operator of the condition of the electrical system. An example of the invention comprises a plug-in housing for use in a vehicle accessory-power-socket. Additionally, a method of market distribution is disclosed.

Abstract: A method of measuring a motor constant is provided in a vector control apparatus for an induction motor. A voltage output phase ?v is set at a previously set arbitrary phase. Prior to applying a current, a current command is fed to operate the vector control apparatus with a proportional-plus-integral controller being set operative. After conduction for a predetermined time, the gain of the proportional-plus-integral controller is set to zero to maintain an integrated value constant and accordingly fix a voltage command value. In this state, a current command value and a detected current value are measured. This measurement is performed at two levels of current, and a primary resistance value (or a line-to-line resistance value) is derived from the slope.

Abstract: Apparatus and method for real-time analysis of an electric power transmission link status direct buried or installed in a duct or a tunnel are described. The method includes: real-time measuring a surface distributed temperature of the link by using a distributed temperature sensor installed along a longitudinal direction of the link; calculating a conductor temperature of the link on the basis of the surface distributed temperature and an electric current flowing through the link; calculating a heat flow emitted out of the link on the basis of the surface distributed temperature and the conductor temperature; and real-time calculating a thermal parameter of an environment around the link on the basis of the heat flow. Thus, it is possible to calculate operating conditions of the link more accurately and improve safety of electric power transmission by real-time calculating the thermal parameter of the environment around the link.

Abstract: A test machine (10) is provided with a integrating circuit (102) so that when a integrated circuit (12) is inserted in the test machine an external feedback loop between an input (120a) and an output (124a) of a comparator (122) in the integrated circuit under test is established. Thus an input voltage of the comparator (122) oscillates around a threshold level of the comparator (122). A test result is determined dependent on an average value of an oscillating voltage in the feedback loop. In an embodiment the feedback loop is realized with a digital test tester (100, 104, 106) with an added analog integrating circuit added to its output (14).

Abstract: A universal power measurement SoC includes an analog signal conditioning circuit, analog-to-digital converter circuit, memory and micro control unit. The analog signal conditioning circuit receives physical signals from a signal sensor and adjusts the polarities and amplitudes of the signals to produce suitable analog signals and gain status. The analog-to-digital converter circuit converts the adjusted analog signals into digital signals. The memory stores the pre-setup parameters of the power measurement. The micro control unit, according to users' choices, processes the converted digital signals with the gain status to produce the output signals of the power measurement.

Abstract: A current sense resistor circuit using Kelvin connection sense features provides an average voltage across net sense resistance and average voltage across net reference resistance to be available at the Kelvin connection points. The Kelvin connections can be used by a negative feedback gain loop to hold the average current through respective reference elements and sense elements substantially constant.

Abstract: A circuit for detecting a defect of electronic components in an electronic control unit includes an output for driving a load (3). A redundant measurement of the current (IL) is executed at the contacts (G, S, D), in particular at the driven contacts (S, D), of one or more semiconductor circuit elements, and an error function of a semiconductor circuit element is detected when the comparison of two current values (IS, ISense1, ISense2) by way of the current flowing through a load (3, 3?) indicates an unequal current distribution. This circuit is of use in electronic brake force or driving dynamics controllers for motor vehicles.

Abstract: An instrument which utilizes this invention is a pulse generator which has adjustable rise and fall time. The generation of timing of pulses is under control of a digital circuit, and the timing of the beginning and end of each pulse and thus duty cycle is precise. The pulse generator also has an analog-to-digital converter that is used to measure voltages internal to the instrument. Voltage measurements are used to calculate the rise and fall times of the pulses. The rise and fall time of the pulses are adjusted based upon mathematical calculations. Control of rise and fall times is implemented using circuitry internal to the pulse generator. Rise time and fall time circuitry adjusts the rate of change of voltage (dv/dt) on the pulses generated. Rise time and fall time are independently adjustable.

Abstract: An automated test method for performing a hi-pot test procedure for an electrical device through the use of a test program installed in a factory information system (FIS) and a test instrument connected to the FIS. The test program sends a control command to the test instrument that in turn executes the hi-pot test for the electrical device. Test results are obtained by the test program from the test instrument and sent to the FIS. The test results are stored in the FIS for future reference.

Abstract: A method for analyzing electromigration and voltage drop effects in wire segments forming a power-bus grid of an integrated circuit. A floor plan design is created by mapping wire segments to various metal layers in the IC core. Digital, analog, and memory power zones indicating the power consumption of regions within the core are also mapped to the core. An equivalent circuit of the floor plan is generated in a netlist. The netlist is simulated, with the current density and voltage drop of power-bus wire segments calculated. Calculated current density and voltage drop values are analyzed in the floor plan design using a color map to indicate the current density and voltage drop levels of the wire segments. The designer can modify the floor plan design quickly and easily if the calculated current density and voltage drop values indicate potential electromigration or voltage drop problems.

Abstract: Improved endpoint detection and/or thickness measurements may be obtained by correcting sensor data using calibration parameters and/or drift compensation parameters. Calibration parameters may include an offset and a slope, or other parameters. Drift compensation parameters may include off-wafer measurements.

Abstract: The invention relates to a digital circuit making it possible to measure the effective voltage of a signal, comprising at least one module exhibiting a sampler stage exhibiting an output generating an output logic signal which, for each given sampling period, exhibits a level representing the value of the voltage of the signal with respect to a given threshold (A), characterized in that it comprises a circuit (CIRC) for calculating a value representative of said effective voltage as a function of the difference between the number of times the output logic signal indicates that the voltage of the signal is above the given threshold (A) and the number of times the output logic signal indicates that this value is below said given threshold (A) over a duration corresponding to N given sampling periods.

Abstract: A technique for determining performance characteristics of electronic devices and systems is disclosed in one embodiment, the technique is realized by measuring a first response on a first transmission line from a single pulse transmitted on the first transmission line, and then measuring a second response on the first transmission line from a single pulse transmitted on at least one second transmission line, wherein the at least one second transmission line is substantially adjacent to the first transmission line. The worst case bit sequences for transmission on the first transmission line and the at least one second transmission line are then determined based upon the first response and the second response for determining performance characteristics associated with the first transmission line.

Abstract: A synchronous vector measuring device can measure an absolute phase angle of a synchronous vector excellent in continuous numerical stability at high speed and with high accuracy in a noisy electric power system. A voltage measuring part measures the voltage of the electric power system at a period equal to 1/4N (N being a positive integer) of one period of a reference wave. A voltage root-mean-square value calculation part calculates, at each voltage measuring timing, a voltage root-mean-square value at a specific timing from the voltages measured at past 4N timings including the specific timing. An absolute phase angle calculation part makes, at each voltage measuring timing, an inverse cosine of a value obtained by dividing the voltage measured at the specific timing by the product of the voltage root-mean-square value and the square root of 2, as the absolute phase angle of the synchronous vector at the specific timing.

Abstract: A switching semiconductor device (11) provided in a semiconductor module (10) includes a plurality of switching semiconductor elements. A loss calculating section (12) calculates a power loss generated in the switching semiconductor device (11) based on a voltage of each of the switching semiconductor elements which is measured by a voltage measuring section (13) and a current of each of the switching semiconductor elements which is measured by a current measuring section (14). The loss calculating section (12) outputs loss data indicative of the power loss thus calculated as a data signal to a motor control section (82) provided on the outside of the semiconductor module (10). The motor control section (82) can recognize the power loss generated in the switching semiconductor device (11) from the loss data.

Abstract: A system operable to detect voltages within an electrical device and provide an output based on the voltages detected by the system. The electrical device may include an isolation switch adapted to selectively isolate the electrical device from an electrical bus. The system may be operable to detect voltage data in the electrical bus and the electrical device downstream of the isolation switch. The system may provide an indication that voltage is detected in the electrical bus, but that no hazardous voltages are detected within the electrical device downstream of the isolation switch. The system may be adapted to produce a plurality of outputs based on the voltage data detected on the electrical bus and in the electrical device downstream of the isolation switch.

Abstract: In one embodiment, a circuit measures picoampere current levels. The circuit comprises: an operational-amplifier that has differential inputs and differential outputs; a switching structure that switchably couples an input line to one of the differential inputs in response signals from a timing circuit; a first integrating capacitor coupled to one of the differential inputs and to one of the differential outputs; a second integrating capacitor coupled to the other of the differential inputs; and a charge injection compensation structure that selectively injects charge into the input line and removes charge from the input line in response to signals from the timing circuit.

Abstract: Disclosed herein is a method and system for calibrating line drive currents in systems that generate data signals by varying line drive currents and that interpret the data signals by comparing them to one or more reference voltages. The calibration includes varying the line drive current at a transmitting component. At different line drive currents, a receiver reference voltage is varied while the transmitting component transmits data to a receiving component. At each line drive current, the system records the highest and lowest receiver reference voltages at which data errors do not occur. The system then examines the recorded high and low receiver reference voltages to determine a desirable line drive current.

Abstract: An apparatus for calculating an effective voltage is provided, which includes a voltage reducer, an analogue to digital converter, a first detector, a second detector and a calculator. The voltage reducer steps down instantaneous output voltages of a generator. The analogue to digital converter converts each analogue signal of the instantaneous output voltages into a digital signal. The first detector detects a first signal of digitized instantaneous output voltage. The second detector detects a second signal, which differs in terms of phase by 120 deg. from the first signal. The calculator calculates an effective voltage according to the first and second signals, by executing a calculation with an expression: E={2(Va2+VaVb+Vb2)/3}1/2, where E represents the effective voltage, Va the first signal of instantaneous output voltage and Vb the second signal, respectively.

Abstract: A system for field substitution of components of a RF metrology system. The system includes a sensor/cable combination and an analysis unit. Parameters of the RF metrology system are determined prior to placing the RF metrology system in the field. From these parameters, either component, the cable/sensor combination or the analysis module, may be substituted in the field by recalibrating the system for the substituted unit. Such recalibration is carried out utilizing the parameters determined prior to placing the RF metrology system in the field.

Abstract: An apparatus (10) having a portable power source (11) can make use of a plurality of differing charge depleted threshold values (and, in a preferred embodiment, corresponding visual charge-remaining indicators) to determine what level of charge remains in the portable power source (11). This in turn permits the recharging advice as suggested by the visual indicator to better track and reinforce the ordinary recharging behaviors of a given user. So configured, the total lifetime of the portable power source may be extended while also ensuring that the portable power source will be fully charged upon completion of each charging cycle.

Abstract: Embodiments are provided for testing termination circuits in SCSI bus controllers. In one embodiment, the termination circuits are tested by sending test data between respective SCSI controllers of the termination circuits for varying enabled/disabled statuses of the termination circuits.

Abstract: A first resistor is connected in parallel with a second resistor having a lower resistance than the first resistor. The voltage at the terminal of the first resistor is compared with a first threshold voltage, and the voltage at the terminals of the second resistor is compared with a second threshold voltage. A switching device either connects the first resistor in series in a remote power feed circuit, if the switching device detects that the remote power feed current is less than a third threshold current that is between the first and second threshold currents, or connects the second resistor and the first resistor, connected in parallel, in series in the remote power feed circuit if the switching device detects that the remote power feed current is greater than the third threshold current.

Abstract: Before a washing machine is switched over to a very high spin speed in the spin program of the washing machine, the existing imbalance due to irregular distribution of laundry in the drum should be checked. If the imbalance is too strong, the spin program should be interrupted if there is a threat of excessively high bearing forces to be expected. The fluctuation in rotary speed, which may have a high frequency due to the drum speed, and of the power consumption of the washing machine motor measured downstream of the direct current intermediate circuit prior to the feed thereof into the inverter for producing the rotary field in the motor. There, the vector product of the current and the voltage for imbalance measurement by determining power is blocked off from mains network interference effects by the high capacitance of the direct current intermediate circuit.

Abstract: A fluid pump system includes a pump having a plurality of cylinders, each having an outlet port coupled to a high-pressure manifold. A pressure transducer is coupled to the manifold and configured to convert pressure levels of fluid in the manifold to a voltage signal at an output of the transducer. The system further includes a digitizer configured to convert the voltage signal from the transducer to a digital signal at a digitizer output, such that when a value of the voltage signal is less than a selected reference voltage a first digital value is produced, and when the voltage level exceeds the selected reference voltage a second digital value is produced. A diagnostic circuit having an input coupled to the digitizer output is configured to detect malfunctions of the pump based upon characteristics of the digital signal.

Abstract: A fuel cell generation system employing a load following algorithm that provides the desired output power from the fuel cell on demand. The system includes a draw current sensor that measures the current drawn from the fuel cell used to satisfy the system load demands. The load following algorithm uses the measured draw current to identify the proper amount of fuel and air to meet the load demands, and then provides a buffer of extra fuel and air to the fuel cell so if the load demand suddenly increases, the fuel cell is able to immediately produce the extra output power. As the current drawn from the fuel cell changes in response to changing load demands, the load following algorithm causes the amount of fuel and air being applied to the fuel cell stack to increase and decrease so that the buffer of extra fuel and air is maintained substantially constant.

Abstract: Methods and devices for monitoring distributed electric power are disclosed, including energy devices with a sensor for monitoring an electric circuit, and a memory to store sensor measurements. Various techniques are disclosed for using polymeric RAM, 1T-DRAM, enhanced SRAM, magnetoresistive RAM, organic RAM, chalcogenide RAM, holographic memory, PLEDM, single-electron RAM, fractal cluster glass memory and other technologies in energy devices with high-endurance, high-density, high-capacity, non-volatile, solid-state, or removable memories.

Abstract: A system and method for measuring integrated circuit processor power demand comprises calibrating one or more voltage controlled oscillators for use as ammeters, calibrating a calibration current source, wherein the calibration current source draws current through a inherent resistance, calibrating the inherent resistance, and interleaving said calibrations in time with calculating the processor power demand using a voltage that is measured across the inherent resistance.

Abstract: A method of screening defects includes steps of: (a) measuring a quiescent current at a first supply voltage for each of a plurality of devices; (b) measuring a quiescent current at a second supply voltage for each of the plurality of devices; (c) generating a plot of the quiescent current measured at the first supply voltage vs. the quiescent current measured at the second supply voltage for each of the plurality of devices; (d) determining a range of intrinsic variation of quiescent current in the plot; and (e) identifying any of the plurality of devices corresponding to a measurement plotted outside the range of intrinsic variation as defective.

Abstract: Methods are disclosed for calculating the amount of voltage coupled to a device. In some embodiments, the method may comprise identifying a conductor that is coupled to a device, extracting information regarding the relationship between the conductor coupled to the device and adjacent conductors, extracting information regarding signals that are present in the adjacent conductors, partitioning the signal information into phases, calculating a voltage induced in the conductor coupled to the device during each phase of the partitioned signal, calculating an average voltage induced in the conductor coupled to the device and, flagging the device if the average voltage induced is above a predetermined threshold.

Abstract: A control arrangement and method is provided for detecting and responding to disturbances in electrical power systems. In a preferred arrangement, an integration is initiated that is based on a comparison of actual voltage of a source and a reference voltage. When the integration exceeds a predetermined value, the source is considered unreliable. Also in a preferred arrangement, a determination is made as to whether or not the disturbance is a downstream fault condition. For example, this is useful for applications where a transfer is made from a first source to a second source when predetermined disturbances are detected. In this manner, the transfer of the load to a second source is avoided which would continue the supply of the downstream fault. Additionally, the arrangement distinguishes between various degrees of disturbances to permit appropriate response based on the severity and type of disturbance. For example, a first immediate response, i.e.

Abstract: The present invention provides an apparatus and method for inspecting electrical continuity of a circuit board, capable of decreasing the impedance in a current path as an inspection object to achieve enhanced SN ratio. A coupling capacitance is formed at one of terminals of a pattern wire on a board as an inspection object in a non-contact manner, and an inductance (450) and a lead wire are connected to this capacitance. An AC inspection signal is applied to the other terminal through the lead wire in a contact manner. A resonance circuit is defined by the capacitance, inductance and pattern wire, and thereby an output signal can be detected with lowering the impedance.