Abstract: In an embodiment, a method includes: wirelessly transmitting power to a receiving coil from a transmitting coil, where the receiving coil is in a wireless power transmission space of the transmitting coil; measuring an output of a sensor during a first time to generate a first measurement; measuring the output of the sensor during a second time to generate a second measurement, the second time being after the first time; and when a magnitude of a difference between the first measurement and the second measurement is higher than a predetermined threshold, stopping wirelessly transmitting power to the receiving coil with the transmitting coil.

Abstract: A magnetic sensor includes at least one MR element and a coil. The coil includes at least one conductor portion. The at least one conductor portion is each located at a position such that a partial magnetic field generated by the conductor portion is applied to one of the at least one MR element, the one corresponding to the conductor portion, and extends along an imaginary curve curving to protrude in a direction away from the corresponding MR element.

Abstract: A system includes a voltage source, a current source, and a testing station. The testing system is arranged to mechanically and electrically connect to multiple head gimbal assemblies (HGAs) simultaneously, and the testing station includes conductors for electrically coupling to conductive pads of the HGAs. The system further includes memory containing instructions for causing a computing device to connect either the voltage source or the current source to the conductors corresponding to each of the HGAs to be connected to the testing station.

Abstract: In example embodiments, an RF-to-DC converter includes one or more unit cells that integrate a spintronic element (e.g., a magnetic tunnel junction (MTJ)) into a conductor ring RF energy absorber (e.g., a split-ring resonator (SRR)). A RF-to-DC converter that includes one or more MTJ-integrated SRR unit cells may provide compactness, as each unit cell includes its own independent SRR and integrated MTJ; scalability, as multiple unit cells may be connected into an array to increase DC power output; and energy harvesting efficiency, as a MTJ may be much more sensitive than a Schottky diode and the SRR of each unit cell may directly feed energy to a MTJ without impedance matching circuits.

Abstract: The present invention discloses an intruding metal detection method for a supplying-end module of an induction type power supply system having a supplying-end coil controlled by a first driving signal and a second driving signal. The method includes periodically generating a detection signal on the first driving signal and the second driving signal, wherein the detection signal controls the supplying-end coil to resonate and generate a coil signal; setting at least one threshold voltage and comparing a plurality of peak values of the coil signal with the at least one threshold voltage, respectively, to generate a plurality of trigger signals; determining whether to perform a pre-charging procedure according to a resonant frequency of the coil signal; and determining whether there is an intruding metal existing in a power supply range of the induction type power supply system according to the plurality of trigger signals and the resonant frequency.

Abstract: A filter assembly has a qualified filter element that filters fuel, a filter housing for the qualified filter element and a water-in-fuel sensor that senses presence of water in the filter housing. An electrical resistance of the water-in-fuel sensor changes based upon whether the qualified filter element is installed in the housing. A filter assembly can also have a plurality of magnetic elements disposed on at least one of the filter housing and the qualified filter element. A plurality of wires are disposed on at least the other of the filter housing and the qualified filter element. The control circuit determines that the qualified filter element is installed in the filter housing based on a change in the electrical current in the plurality of wires.

Abstract: A failure detecting apparatus that detects an isolation failure between a plurality of coils included in a signal detection apparatus. The failure detecting apparatus includes a voltage applying unit that applies a DC voltage to a coil in the plurality of coils; a differential signal generating unit that generates a differential signal from a voltage at the coil and a predetermined voltage; a threshold voltage setting circuit that outputs a threshold voltage; and a comparator that compares the differential signal with the threshold voltage, thereby detecting whether or not an isolation failure exists. The differential signal generating unit includes either first setting unit for setting an absolute value of the differential signal to be amplified with a predetermined gain or second setting unit for setting the predetermined voltage to be different from a ground potential, and the predetermined gain is set to a value different from one and zero.

Abstract: A hardware-only contactless position sensor system is provided that includes a contactless position sensor and hardware-only sensor system electronics. The sensor includes excitation, sine, and cosine coils. The electronics are coupled to the sensor and detect a position of a target relative to the sensor. The electronics include a phase shift and summation circuit that applies a phase shift at a frequency of the excitation coil to one of a sine signal from the sine coil or a cosine signal from the cosine coil as a phase shifted signal and add the phase shifted signal with an unshifted instance of the cosine or sine signal to produce a phase shifted output. The electronics also include a phase detector circuit that detects a phase of the phase shifted output and generate an output voltage corresponding to the phase and proportional to the position of the target.

Abstract: A method for recognizing a manipulation of at least one electrical line includes determining a parameter that is dependent on a resistance and a capacity, a resistance and an inductivity, or a resistance, a capacity, and an inductivity of the electrical line; comparing the determined parameter to a reference parameter to provide a comparison result; and recognizing a manipulation of the electrical line based on the provided comparison result.

Abstract: Present techniques provide an inductive proximity sensor having a multi-receiver coil assembly and an evaluator circuit configured to receive a differential signal from the multi-receiver coil assembly to determine the presence of a target. The multi-receiver coil assembly includes two receiver coils in a differential coil arrangement and a transmitter coil configured to emit an electromagnetic field and induce a voltage on each of the receiver coils. The voltage difference between the two receiver coils is transmitted as a differential signal to the evaluator circuit. Targets which approach the inductive proximity sensor disrupt the electromagnetic field and change the induced voltages on each of the receiver coils, thereby changing the differential signal. The evaluator circuit processes the differential signal to determine whether the changes indicate that a target is present.

Abstract: A sensing device is provided. First to third receiving electrodes extend in a first direction. First and third receiving electrodes are respectively disposed on two sides of the second receiving electrode. The first to fourth transmitting electrodes are disposed on a row extending in a second direction. The first and second transmitting electrodes are respectively disposed on two sides of the first receiving electrode, the third and fourth transmitting electrodes are respectively disposed on two sides of the third receiving electrode, and the second and third transmitting electrode are respectively disposed on two sides of the second receiving electrode. The first, second third and fourth transmitting electrodes are independently controlled by a transmitter. A receiver generates a sensing signal according to a signal level is at least one of the first, second, and third receiving electrodes.

Abstract: A method for determining residual coupling of an inductive, conductivity sensor, in which the conductivity sensor is surrounded by a measured medium and an equivalent impedance of the medium is calibrated with a variable compensation impedance. The variable compensation impedance and the equivalent impedance of the medium act on a measuring coil of the conductivity sensor with a phase shift of 180°. In order to be able to perform a measuring of the residual coupling with a high accuracy of measurement at any time during operation of the conductivity sensor, the variable compensation impedance is varied until an output voltage of the measuring coil of the conductivity sensor assumes a minimum voltage; wherein the minimum voltage corresponds to the residual coupling of the inductive, conductivity sensor.

Abstract: A method for sensing analyte. The method includes the steps of sensing one or more parameters in reaction to the presence of one or more analytes and outputting a current therefrom in accordance with level of the sensed parameter by each of a plurality of sensors, each of the plurality of sensors being provided in one or more sensor array columns, selectively heating one or more of the sensor array columns by a heating element, and receiving an output current from one of the plurality of sensors from each of the plurality of sensor arrays by a Voltage Controlled Oscillator (VCO) arranged in a VCO array. The method further includes the steps of generating an output oscillation frequency by each VCO in accordance with the level of the received output current, and counting a number of oscillations over a predetermined time received from each of the plurality of VCOs in the VCO array by a plurality of counters arranged in a counter array.

Abstract: An embodiment relates to an integrated circuit comprising measurement means for detection of a current change, wherein said measurement means comprise at least one coil.

Abstract: A refillable and implantable infusion apparatus and method that includes a needle penetration detector that detects and indications the position of a needle relative to a septum of a drug reservoir of the implantable infusion apparatus. With the needle position data, medical professionals may better ensure they are injecting drugs into the drug reservoir, thus, improving patient safety.

Abstract: An inductive sensor includes a primary winding, two secondary windings and a moveable target, the primary winding being centered about a central axis and carrying a high-frequency alternating current which can induce a voltage in secondary windings, the secondary windings also being centered about the central axis and made up of a number k of substantially identical loops, which are successively crossed and arranged opposite the primary winding. In this case, the target is made up of a part having p=1 angular sector with an angular opening. The opening of the angular sector of the target is less than that of a loop of secondary winding with a deviation calculated such as to eliminate the fourth harmonic of the linearity deviation Fourier decomposition, between the measured angular value and real angular value for the position of the target over the measurement course.

Abstract: The disclosure features apparatus, methods, and systems for wireless power transfer that include a power source featuring at least one resonator, a power receiver featuring at least one resonator, a first detector featuring one or more loops of conductive material and configured to generate an electrical signal based on a magnetic field between the power source and the power receiver, a second detector featuring conductive material, and control electronics coupled to the first and second detectors, where during operation, the control electronics are configured to measure the electrical signal of the first detector and compare the measured electrical signal of the first detector to baseline electrical information for the first detector to determine information about whether debris is positioned between the power source and the power receiver.

Abstract: This invention provides methods and devices for detecting the viscosity and conductivity of a conductive fluid sample. A sample fluid can be received into a sample chamber between a field inductor and sensor inductor. Electromagnetic fields generated by the field inductor can be modulated due to the counter-emf induced in the sample. The modulations can be detected by the sensor inductor and correlated to electric parameters in the fluid.

Abstract: Operative monitoring of track brakes involves passing an electric current through a winding of a brake magnet, measuring the electric current and comparing the temporal progression of the measured current with a saved temporal progression of a reference current. Comparison is achieved by calculating the difference between the measured current and the reference current. The difference between measured current and reference current may be temporally integrated and compared with a threshold value. To determine a magnetic coupling between track brake and track, a calculation may be made as to whether the measured current has local minima and/or local maxima during the activation of the track brake, only the temporal progression of the measured current as the current increases being subjected to a comparison with the reference current. The current may be activated in pulses, with the comparison of the measured current and the reference current being restarted with each pulse.

Abstract: A method for operating a magneto-inductive flow measuring device having a measuring tube, wherein an at least partially electrically-conductive measured material flows through the measuring tube. For determining flow, there is produced by means of at least one coil arrangement a clocked magnetic field, which at least partially passes through the measured material, wherein the magnetic field is produced by an exciter current, which flows through the coil arrangement. The magnetic field is operated with at least a first clocking, wherein, in a case in which the coil arrangement is free of exciter current, an electrical potential difference is sensed between the measured material and a reference potential by means of at least a first measuring electrode communicating with the measured material.

Abstract: A device for use with a conduit having a first conduit end and a conduit second end, into which conduit a cable can be installed using a flow of air into the first conduit end, the device being suitable for confirming that the air is flowing out from the second conduit end. In an embodiment, the device includes a housing, means to enable connection of the device to the second conduit end, a detector arranged to detect an electrical property change, and an actuator for causing an electrical property change detectable by the detector, wherein in use, the air flowing into the device causes the detector and the actuator to move relative to each other, causing an electrical property change detectable by the detector.

Abstract: This invention relates to non-contact measurement methods and an apparatus for the identification of hazardous contact voltages on energized objects and surfaces. The apparatus includes an electric field sensor structured to sense an electric field and a gain amplifier electrically connected to the electric field sensor to amplify electric signals from the electric field sensor. The apparatus further includes a signal conditioning circuit adapted to process the amplified electric signals and form time-coordinated signals and a digital signal processor adapted to evaluate the time-coordinated signals and provide a user with a status of a contact voltage source by activating an appropriate status indicator.

Abstract: A filter assembly has a qualified filter element that filters fuel, o filter housing for the qualified filter element and a water-in-fuel sensor that senses presence of water in the filter housing. An electrical resistance of the water-in-fuel sensor changes based upon whether the qualified filter element is installed in the housing. A filter assembly can also have a plurality of magnetic elements disposed on at least one of the filter housing and the qualified filter element. A plurality of wires are disposed on at least the other of the filter housing and the qualified filter element. The control circuit determines that the qualified filter element is installed in the filter housing based on a change in the electrical current in the plurality of wires.

Abstract: The inductive incremental displacement sensor is characterized in that the first sensor unit and the second sensor unit each have a first inductive sensor and a second inductive sensor disposed at a distance from each other and that the first sensor unit and the second sensor unit deliver a switching signal relevant to a conductive region of the graduated track when the difference or the ratio of the detection signals from the inductive sensors allocated to the respective sensor unit as generated by the conductive region is less than a specifiable threshold. Furthermore, the invention relates to a method for determining the displacement of a first object relative to a second object as well as to an inductive sensor unit.

Abstract: A method for operating an inductive conductivity-measuring cell having a primary circuit with a sending coil, a secondary circuit with a receiver coil, and a short-circuit path, which passes through the sending coil and the receiver coil. The sending coil couples via the short-circuit path inductively with the receiver coil, wherein, in the case of closed short-circuit path, a first electrical signal present in the primary circuit is measured, and wherein the first signal is compared with, and/or weighed against, values, which are furnished or stored.

Abstract: An integrated circuit device inductive touch analog front end excites selected ones of a plurality of inductive touch sensors and provides analog output signals representative of voltages across the coils of the plurality of inductive touch sensors. Various characteristics of the inductive touch analog front end are programmable. A digital processor controls selection of each one of the plurality of inductive touch sensors and receives the respective analog output voltage signal from the inductive touch AFE. The digital processor may program the characteristics of the inductive touch analog front end. When a sufficient change in the coil voltage is determined by the digital processor, that inductive touch sensor is assumed to have been actuated and the digital processor takes action based upon which one of the plurality of inductive touch sensors was actuated (touched).

Abstract: A method for measuring values from a sensor cell having the basic structure of an MOS silicone transistor having and including a polymer material therein. The method includes the steps of expelling an analyte from the polymer material, determining a silicon current signature before analyte accumulation in a sensitive response region, introducing analyte into the polymer material, determining the silicon current signature immediately after analyte introduction, determining the organic current signature immediately after analyte introduction, allowing analyte accumulation in the polymer material, determining the silicon current signature after analyte accumulation, determining the organic current signature after analyte accumulation, and determining the silicon current signature after analyte accumulation in sensitive response region.

Abstract: Present techniques provide an inductive proximity sensor having a multi-receiver coil assembly and an evaluator circuit configured to receive a differential signal from the multi-receiver coil assembly to determine the presence of a target. The multi-receiver coil assembly includes two receiver coils in a differential coil arrangement and a transmitter coil configured to emit an electromagnetic field and induce a voltage on each of the receiver coils. The voltage difference between the two receiver coils is transmitted as a differential signal to the evaluator circuit. Targets which approach the inductive proximity sensor disrupt the electromagnetic field and change the induced voltages on each of the receiver coils, thereby changing the differential signal. The evaluator circuit processes the differential signal to determine whether the changes indicate that a target is present.

Abstract: The invention relates to a method for measuring a distance between a coordinate indicator and a coordinate input device, which belongs to the technical field of computer peripheral equipments. The method comprises the steps of measuring an actual amplitude of an output signal of a receiving coil in the electromagnetic induction plate by a measurement circuit in the electromagnetic induction plate; determining a distance between the coordinate indicator and the coordinate input device in accordance with the actual amplitude of the output signal, a nominal amplitude of the output signal, and a preset reference amplitude of signal.

Abstract: An efficiency monitor for monitoring the efficiency of power transmission by an inductive power outlet. The efficiency monitor includes an input power monitor, for measuring the input power delivered to the primary coil, and an output power monitor, for measuring the output power received by the secondary coil. The input and output powers are used by a processor to determine an index of power-loss. A circuit breaker may be used to disconnect the inductive power outlet in case of excessive power loss.

Abstract: A method for measuring values from a sensor cell having the basic structure of an MOS silicone transistor having and including a polymer material therein. The method includes the steps of expelling an analyte from the polymer material, determining a silicon current signature before analyte accumulation in a sensitive response region, introducing analyte into the polymer material, determining the silicon current signature immediately after analyte introduction, determining the organic current signature immediately after analyte introduction, allowing analyte accumulation in the polymer material, determining the silicon current signature after analyte accumulation, determining the organic current signature after analyte accumulation, and determining the silicon current signature after analyte accumulation in sensitive response region.

Abstract: An inductive loop presence detector for sensing objects, such as rail cars, containing one or more sensing loops. The inductive loop presence detector includes a backup power supply that is connected to a control unit of the detector to power the control unit during an interruption in the line voltage. The backup power supply includes batteries or capacitors that power the control unit when the line voltage is interrupted. The control unit of the inductive loop presence detector operates in a lower power mode when the control unit is supplied with power from the backup power supply. The control unit operates to auto-tune and supply power to the sensing loops to operate at the most desirable frequency based upon the inductance of the sensing loops.

Abstract: Systems and methods for detecting electromagnetic waves are disclosed. A system for use in detecting an electromagnetic wave includes an inductive device and a spintronic device. The inductive device generates an induced electromagnetic field when the inductive device receives the electromagnetic wave. The spintronic device has an impedance that changes when exposed to the induced electromagnetic field from the inductive device. The change in impedance is indicative of the electromagnetic wave received by the inductive device. Another system for use in detecting or transmitting an electromagnetic wave includes a conductive device and an inductive device. The inductive device is configured to generate an induced electromagnetic wave when the inductive device receives an electromagnetic wave passed by the conductive device. Another system for detecting electromagnetic wave permittivity or permeability of an object includes a pair of antennas and an inductive device.

Abstract: This invention relates to non-contact measurement methods and an apparatus for the identification of hazardous contact voltages on energized objects and surfaces. The apparatus includes an electric field sensor structured to sense an electric field and a gain amplifier electrically connected to the electric field sensor to amplify electric signals from the electric field sensor. The apparatus further includes a signal conditioning circuit adapted to process the amplified electric signals and form time-coordinated signals and a digital signal processor adapted to evaluate the time-coordinated signals and provide a user with a status of a contact voltage source by activating an appropriate status indicator.

Abstract: This invention provides methods and devices for detecting the viscosity and conductivity of a conductive fluid sample. A sample fluid can be received into a sample chamber between a field inductor and sensor inductor. Electromagnetic fields generated by the field inductor can be modulated due to the counter-emf induced in the sample. The modulations can be detected by the sensor inductor and correlated to electric parameters in the fluid.

Abstract: Operative monitoring of track brakes involves passing an electric current through a winding of a brake magnet, measuring the electric current and comparing the temporal progression of the measured current with a saved temporal progression of a reference current. Comparison is achieved by calculating the difference between the measured current and the reference current. The difference between measured current and reference current may be temporally integrated and compared with a threshold value. To determine a magnetic coupling between track brake and track, a calculation may be made as to whether the measured current has local minima and/or local maxima during the activation of the track brake, only the temporal progression of the measured current as the current increases being subjected to a comparison with the reference current. The current may be activated in pulses, with the comparison of the measured current and the reference current being restarted with each pulse.

Abstract: A device for use with a conduit having a first conduit end and a conduit second end, into which conduit a cable can be installed using a flow of air into the first conduit end, the device being suitable for confirming that the air is flowing out from the second conduit end. In an embodiment, the device includes a housing, means to enable connection of the device to the second conduit end, a detector arranged to detect an electrical property change, and an actuator for causing an electrical property change detectable by the detector, wherein in use, the air flowing into the device causes the detector and the actuator to move relative to each other, causing an electrical property change detectable by the detector.

Abstract: A method of diagnosing an electronic display device (1) having a screen (3) and a graphics memory (2) in which image data (14), of an image displayed or to be displayed on the screen (3), are one of stored or changed. A measured value (15) characterizes a current consumption or the change in current consumption of the screen (3) or display device (1) while a reference value (16) characterizes the current consumption or the change in current consumption of the screen (3) or display device (1) on the basis of the image data (14) or the change in image data (14). The method compares the reference value (16) to the measured value (15) to determine any malfunction or error in the electronic display device (1).

Abstract: The present invention relates to an inductive incremental displacement sensor for determining a displacement of a first object relative to a second object, comprising at least one graduated track mountable on the first object and having periodically alternating conductive regions and insulating regions, and having at least one scanning unit mountable on the second object for scanning the graduated track with a first sensor unit and a second sensor unit, which are laterally spaced from each other by a distance d=n*(p/2)+q, wherein n is an integer or zero, p is the pitch of the graduated track and 0 is <|q|<p/2, and, in particular, q=0.25 p and comprising an evaluation unit for determining the displacement on the basis of switching signals delivered by the first sensor unit and the second sensor unit.

Abstract: A capacitive ultrasonic transducer includes a flexible layer, a first conductive layer on the flexible layer, a support frame on the first conductive layer, the support frame including a flexible material, a membrane over the support frame being spaced apart from the first conductive layer by the support frame, the membrane including the flexible material, a cavity defined by the first conductive layer, the support frame and the membrane, and a second conductive layer on the membrane.

Abstract: Systems and methods are provided for sensing or measuring capacitive or inductive reactance or changes in reactance in which the sensed reactance is coupled with a known resistance in a sensor circuit and a start signal is provided to the sensor circuit, and a programmable delay line is used to generate a programmable delay signal. The outputs of the programmable delay and the sensor circuits are compared to ascertain which transitions first, and the programmable delay value is adjusted in successive approximation fashion to identify a programmable delay that best represents the delay time of the sensor circuit from which the sensed reactance value can be determined.

Abstract: The present invention relates to the use of a nanoparticle film having metal ions incorporated wherein and to a method of detecting a gaseous or volatile or liquid analyte in a medium.

Abstract: The present invention discloses an automatic page detector, to determine which page of a book is open. The automatic page detector uses a sensor plate and an inductor as a sensor. In the invention, there is a sensor plate at each page of the book and the locations of the sensor plates for different pages are different. There is an array of inductors just beneath the sensor plates when the book is closed. The inductors are connected to the feedback loop of a LC oscillator through analog switches. The proximity of a sensor plate to an inductor will change the frequency of the LC oscillator. Scanning the analog switches by a microprocessor and detecting the variation of frequency of the LC oscillator during each scanning time period, the status of each sensor plate will be detected and we can determine which page of a book is opened.

Abstract: A sensor for sensing a measurand is described, the sensor comprising a coplanar waveguide with a first surface and a second surface opposite to the first surface; a first structure with a first periodically varying dielectric characteristic, the first structure being arranged on the first surface of the coplanar waveguide; and a second structure with a second periodically varying dielectric characteristic, the second structure being arranged on the second surface of the coplanar waveguide, wherein a unit-cell of the structures with periodically varying dielectric characteristics is dimensioned such that the sensor has a frequency dependent transfer behavior with at least one transfer minimum, and wherein the sensor is implemented such that the measurand influences the first periodically varying dielectric characteristic of the first structure or the second periodically varying dielectric characteristic of the second structure or a relation between such first structure and second structure.

Abstract: Systems and methods are provided for sensing or measuring capacitive or inductive reactance or changes in reactance in which the sensed reactance is coupled with a known resistance in a sensor circuit and a start signal is provided to the sensor circuit, and a programmable delay line is used to generate a programmable delay signal. The outputs of the programmable delay and the sensor circuits are compared to ascertain which transitions first, and the programmable delay value is adjusted in successive approximation fashion to identify a programmable delay that best represents the delay time of the sensor circuit from which the sensed reactance value can be determined.

Abstract: Signal coincidence detection circuits and methods implemented in such circuits are disclosed. An example signal coincidence detection circuit includes a first differential transistor pair, a second differential transistor pair coupled with the first differential transistor pair and a third differential transistor pair coupled with the first differential transistor pair in parallel with the second differential transistor pair. The circuit also includes a first input signal terminal coupled with the first, second and third differential transistor pairs, wherein, in operation, the first input signal terminal receives a first input signal that is communicated to the first, second and third differential transistor pairs.

Abstract: A method of making a resonant frequency tag which resonates at a predetermined frequency. The method involves providing a first conductive pattern having an inductive element and a first land and a second conductive pattern having a second land and a third land which are joined together by a link. The second conductive pattern is overlaid the first conductive pattern such that the second land is positioned over the first land. The third land is in electrical communication with the inductive element of the first conductive pattern. The formed resonant frequency tag is energized to determine if the tag resonates at the predetermined frequency. If the tag resonates properly, the third land is electrically coupled to the inductive element. If it does not, the second conductive pattern is adjusted so that overlapping portions of the first and second lands are changed, altering the capacitance to adjust the resonant tag frequency.

Abstract: A method of making a resonant frequency tag having a predetermined frequency comprises forming a first conductive pattern comprising an inductive element and a first land having a first end connected to an inductive element end, and a second end spaced a predetermined distance from the first end; separately forming a second conductive pattern comprising a second land having a predetermined width and a link element; placing the second conductive pattern proximate the first conductive pattern at a first location wherein the second land overlies a portion of the first land with a dielectric therebetween establishing capacitive element plates having a first capacitance along with the inductive element forming a resonant circuit; measuring the resonant circuit frequency and comparing the measured and predetermined frequencies moving the second land along of the first land length to match the resonant frequency; and securing the second conductive pattern to the first conductive pattern.

Abstract: Inner individual electrodes are formed at intervals on a piezoelectric ceramic layer so as to correspond in a one-to-one relationship with ink channels, and an inner common electrode are formed on another piezoelectric ceramic layer. The required number of piezoelectric ceramic layers with inner individual electrodes and with an inner common electrode are laminated alternately. An outer common electrode is connected to the inner common electrodes, and outer individual electrodes are connected to the respective inner individual electrodes. The capacitance between the outer common electrode and each of the outer individual electrodes is measured. A polarization electric field adjusted based on the measured value is applied between the common electrode and each of the outer individual electrodes to perform polarization.

Abstract: The current mirror configuration includes four branches, a biasing branch, a first comparator branch, a second comparator branch and a measurement branch. The measurement branch is connected to a pad of the IC device and a measurement current is charged on to the pad. The measurement current is mirrored from the current of the biasing branch and the measurement current is mirrored to the second comparator branch. The biasing branch is mirrored to the first comparator branch using a scale that the current of the first comparator branch is smaller than the current of the biasing branch. In case of a short-circuit, the current of the measurement branch is larger than the current of the first comparator branch.