Abstract: A wound dressing (10) including a plurality of discrete, spaced apart pairs of electrodes (18a, 18b) for allowing an electrical property or characteristic of the dressing (10) to be measured. By measuring an electrical characteristic of the dressing, such as the impedance, the hydration thereof can be determined and monitored.

Abstract: There is disclosed herein a method of measuring and profiling a process liquid in a process vessel. The process liquid includes an emulsion layer between two media of differing dielectric constants. An electromagnetic signal is generated and transmitted along a probe, defining a transmission line, extending into the vessel. The transmission line comprises a conductor in contact with the process liquid with an insulating coating on the conductor to maximize signal penetration in the process liquid. A reflected signal is received from the transmission line and a programmed controller is operatively connected to the probe for measuring characteristics of reflected signal energy along the transmission line for profiling the emulsion layer.

Abstract: An apparatus (1) for measuring the loss factor of an insulator (2) for medium or high voltages, equipped with a tap adapter (3) forming a point for picking up an electrical signal (4), comprises a reference capacitor (9) having a first electrode (10), which can be connected to the tap adapter (3), and a second electrode (11); a first voltage detection module (12) operatively connected to the first electrode (10) of the reference capacitor (9) for detecting a signal representative of the voltage applied to the reference capacitor (9); a generator module connected to the first electrode (10) of the reference capacitor (9) in order to inject a direct electric current into the insulator.

Abstract: An integrated circuit compensates for parasitic capacitance in a capacitive measuring apparatus wherein a capacitance measurement is done by repeatedly transferring charge from a capacitor to be measured to a reference capacitor.

Abstract: A touch panel sensor with which unevenness of interference can be reduced is provided. A touch panel sensor of the present invention includes a film base material, a first transparent electrode pattern formed on a first face of the film base material, a first adhesive layer laminated on the first face of the film base material so as to cover the first transparent electrode pattern, a second transparent electrode pattern formed on a second face of the film base material, and a second adhesive layer laminated on the second face of the film base material so as to cover the second transparent electrode pattern, and the film base material has an in-plane phase difference of ?/4 with respect to a wavelength ? in the visible light region.

Abstract: Apparatuses and methods of driving different transmit (TX) phase sequences of a TX signal on TX electrodes in different sensing stages according to a weighting matrix as the excitation matrix. One method drives the TX signals according to the weighting matrix and measures receive (RX) signals on the RX electrodes to determine if an object is proximate to the electrodes.

Abstract: A circuit for measuring a capacitance value of a touch screen includes: a target capacitor unit having a target capacitor charged with a target charging voltage; a target voltage control unit to charge the target capacitor; a reference capacitor unit having a reference capacitor charged with a charging reference voltage; a reference voltage control unit to charge the reference capacitor; a comparator to compare the target charging voltage and the charging reference voltage and output a transition signal at a moment when the target charging voltage becomes higher than the charging reference voltage; and a controller to receive an output signal of the comparator and a clock signal and generate a digital output signal and a control signal, wherein a capacitance value of the target capacitor is measured using a time elapsed from a time when the target capacitor is initialized to a time when the transition signal is outputted.

Abstract: An electrical circuit identification means is revealed. The electrical circuit identification device includes a signal generator connected directly to an AC power socket and a signal receiver set in a power control panel. The signal generator blocks a half cycle of sine waves and produces a short off-and-off signal at an interval. The signal receiver includes a signal sensor receiving signals from the signal generator and connected to both a control voltage divider and a signal strength switch for modulating and amplifying signals received by the control voltage divider, and a signal integration module that is connected to the signal strength switch and a microcontroller for outputting digital signals with different waveform. An identification system in the microcontroller cross checks the digital signals and the identification accuracy is determined according to the position of a light lit up in an indicator light module.

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 system and method for monitoring a dielectric state of high voltage equipment. A leakage current is measured and compared to a programmed limit value. An alarm is activated if the leakage exceeds the limit value to indicate that insulation has seriously deteriorated. The leakage current measurement is verified using a comparison of individual leakage currents with a change in a vector sum of leakage currents.

Abstract: According to the present invention, a small impedance detection circuit capable of accurately detecting the impedance of an object to be measured and an adjustment method of an impedance detection circuit can be provided. In the impedance detection circuit according to the present invention, an AC signal generator outputs an AC signal. A detection circuit, which is connected to a circuit to be measured, applies an AC signal to the circuit to be measured. Further, the detection circuit outputs a first signal corresponding to the composite impedance of the impedance of the circuit to be measured and a parasitic impedance. A correction circuit outputs a second signal in synchronization with the first signal. A subtraction circuit outputs a detection signal obtained by subtracting the second signal from the first signal.

Abstract: The present invention relates to a capacitive sensor system comprising a sensor circuit connected to a first (15) and a second (11) antenna, the first antenna (15) is arranged on a first object (10) and the second antenna (11) is arranged on a second object (11) movable relative to said first object (10). The first antenna (15) is arranged right next to the second object (11) for the sensor circuit to detect the movement and/or position of the second object (11).

Abstract: An apparatus (1) for measuring the loss factor of an insulator (2) for medium or high voltages, equipped with a tap adapter (3) forming a point for picking up an electrical signal (4), comprises a reference capacitor (9) having a first electrode (10), which can be connected to the tap adapter (3), and a second electrode (11); a first voltage detection module (12) operatively connected to the first electrode (10) of the reference capacitor (9) for detecting a signal representative of the voltage applied to the reference capacitor (9); a generator module connected to the first electrode (10) of the reference capacitor (9) in order to inject a direct electric current into the insulator.

Abstract: An apparatus (1) for measuring the loss factor of an insulator (2) for medium or high voltages, equipped with a tap adapter (3) forming a point for picking up an electrical signal (4), comprises: a reference capacitor (9) having a first electrode (10), which can be connected to the tap adapter, and a second electrode (11); a first voltage detection module (12) operatively connected to the first electrode (10) of the reference capacitor (9) for detecting a signal representative of the voltage applied to the reference capacitor (9); an active electronic device (13) connected to earth and to the second electrode (11) of the reference capacitor (9) and configured to keep the potential of the second electrode (11) at a predetermined reference value; a second voltage detection module (14) operatively connected to an output of the active electronic device (13) in order to detect a signal representative of the electric current that flows through the reference capacitor (9).

Abstract: Apparatus and methods for evaluating leakage currents of capacitances are described. Capacitances having excessive leakage currents may be disabled from use. An example apparatus includes a leakage detection circuit configured to be coupled to a capacitance block. The leakage detection circuit is configured to determine whether a leakage current of a capacitance of the capacitance block exceeds a current limit and is further configured to provide an output indicative of a status of the capacitance. A detection controller is coupled to the leakage detection circuit and a register, and the detection controller is configured to store data in the register indicative of the status of the capacitance based at least in part on the signal from the leakage detection circuit.

Abstract: A capacitor capacitance diagnosis device includes a power supply which is for charging a capacitor, a discharge circuit which is connected to the capacitor in parallel to discharge energy of the capacitor, a resistance dividing circuit which is for measuring voltage drop value during discharging, a measurement circuit which measures divided voltage, and a diagnosis circuit which determines adequacy of capacitor capacitance from a time change in voltage due to the discharge. This makes it possible to diagnose adequacy of capacitor capacitance of an electric power apparatus during operation.

Abstract: A processing system for a capacitive input device is described. The capacitive input device includes a plurality of sensor electrodes configured to detect input objects in a sensing region. The processing system configured to transmit a signal on a transmitter sensor channel of the capacitive input device. The processing system is also configured to receive the signal on a receiver sensor channel of the capacitive input device, wherein the receiver sensor channel is coupled with an amplifier. The processing system is also configured to determine if a level of interference has been received by the receiver sensor channel in conjunction with receipt of the signal.

Abstract: A partial discharge analysis (PDA) coupling device is provided. In one embodiment, a device includes: a connector electrically connecting a first coupling capacitor and a second coupling capacitor; a first conductive rod for electrically connecting the first coupling capacitor to a high voltage input; a second conductive rod for electrically connecting the second coupling capacitor to ground; a current transformer substantially surrounding a portion of the second conductive rod, the current transformer configured to generate a pulse signal; and a reference signal generator adjacent to the current transformer configured to generate a reference signal in phase with the pulse signal.

Abstract: In a method of determining interference in a capacitance sensor, a signal is transmitted on a transmitter sensor channel of the capacitive sensor. The signal is received on a receiver sensor channel of the capacitive sensor, the receiver sensor channel being coupled with an amplifier. Behavior of the amplifier is examined for non-linearity to determine if a level of interference has been received by the receiver sensor channel in conjunction with receipt of the signal.

Abstract: A touch apparatus includes a touch unit, a detecting unit, and a compensation unit. The touch unit has a touch substrate and at least one conductive layer. The conductive layer is disposed on the touch substrate. The detecting unit is electrically connected with the conductive layer of the touch unit and outputs a driving signal to the conductive layer. A first parasitic capacitance is formed between the detecting unit and a ground. The compensation unit is electrically connected with the detecting unit and the touch unit and outputs a compensation signal to the first parasitic capacitance. Hence, the touch apparatus can eliminate the parasitic capacitance effect.

Abstract: The present invention discloses a circuit for detecting capacitance attenuation of a rectification/filter capacitor and a method thereof. A rectification circuit provides a capacitor with a rectified ripple voltage having a maximum lower than output voltage of a back-up power supply device. An isolation device isolates the rectified ripple voltage and let the back-up power supply device supply power to other power supply devices. The detection switch of an detection circuit is turned on to electrically connect the capacitor with a resistor, whereby the resistor conducts the rectified ripple voltage to charge and discharge the capacitor to obtain a peak-to-valley ratio and a discharging time. The capacitance is worked out from the peak-to-valley ratio, discharging time and resistance of the resistor. The deterioration extent of the capacitor is obtained from the variation of the capacitance. Therefore, the UPS system would not be shut off during detecting the capacitor.

Abstract: An apparatus for detecting leakage current through a solenoid coil that includes a capacitor connected to one end of the solenoid coil and a feedback circuit that monitors the rate of decay of the capacitor voltage to determine if an excessive leakage current is present.

Abstract: According to the present invention, a small impedance detection circuit capable of accurately detecting the impedance of an object to be measured and an adjustment method of an impedance detection circuit can be provided. In the impedance detection circuit according to the present invention, an AC signal generator outputs an AC signal. A detection circuit, which is connected to a circuit to be measured, applies an AC signal to the circuit to be measured. Further, the detection circuit outputs a first signal corresponding to the composite impedance of the impedance of the circuit to be measured and a parasitic impedance. A correction circuit outputs a second signal in synchronization with the first signal. A subtraction circuit outputs a detection signal obtained by subtracting the second signal from the first signal.

Abstract: “Improvements Introduced in Monitoring System of Dielectric State of High Voltage Equipments with Capacitive Insulation, Such as Condensive Bushings, Current Transformers, Potential Transformers and Similar” allow to detect quick evolution insulation deteriorations and to emit correspondent alarms, being also able to verify their consistency in order to avoid false alarms as well as to automatically disconnect the equipment in case of a critical deterioration; it also allows to monitor in real time the BPDs quipped condensive bushings state as well as the bushings applied in HVDC high voltage direct current.

Abstract: Described herein are techniques for determining a board parasitic capacitance of a crystal oscillator circuit. A crystal's frequency is measured under load condition off-circuit. After coupling the crystal to the oscillator circuit, external capacitors may be adjusted to produce frequencies approximating the off-circuit measurement with upper and lower margins. Calculation of the load capacitor values at the exact frequency measured off-circuit allows for derivation of the board parasitic capacitance by subtracting the calculated capacitor values from the original total load value used in the off-circuit measurement.

Abstract: A method for determining resistances of defects in a test structure, comprising: forming a first layer of the test structure having elements under test; generating a first e-beam image of the first layer, the first e-beam image graphically identifying defects detected at the first layer, each defect at the first layer having a corresponding grey scale level; adding capacitance to the structure by forming a metal layer of the structure; generating a second e-beam image of the metal layer, the second e-beam image graphically identifying defects detected at the metal layer, each defect at the metal layer having a corresponding grey scale level; generating a pattern of grey scale levels for each defect based on the corresponding grey scale level of each defect at each layer of the test structure; and determining a resistive range of each defect based on the pattern of grey scale levels generated for each defect.

Abstract: A circuit and method for capacitor effective series resistance measurement. One embodiment provides a method for measuring the effective series resistance of a capacitor having a capacitor voltage. The method includes amplifying the capacitor voltage with an AC coupled amplifier yielding a first amplified signal. The capacitor is discharged with a constant current for a measurement time thus causing a voltage swing of the capacitor voltage due to a voltage drop across the effective series resistance. The capacitor voltage is amplified with the AC coupled amplifier yielding a second amplified signal being dependent on the voltage swing. The effective series resistance is calculated from the first and the second amplified signals.

Abstract: A high-density deep trench capacitor array with a plurality of leakage sensors and switch devices. Each capacitor array further comprises a plurality of sub-arrays, wherein the leakage in each sub-array is independently controlled by a sensor and switch unit. The leakage sensor comprises a current mirror, a transimpedance amplifier, a voltage comparator, and a timer. If excessive leakage current is detected, the switch unit will automatically disconnect the leaky capacitor module to reduce stand-by power and improve yield. An optional solid-state resistor can be formed on top of the deep trench capacitor array to increase the temperature and speed up the leakage screening process.

Abstract: An insulation state detector includes a capacitor, a measurement section measuring a charging voltage of the capacitor, a measuring circuit that connects the capacitor, which is insulated from a DC power source after being charged by the DC power source, between the measurement section and a ground potential portion, a detector detecting an insulation state of a voltage boosting circuit, and a reversed-polarity measuring circuit that connects the capacitor to the measurement section and the ground potential portion with reversed polarity when a potential corresponding to a division ratio of a positive-side ground fault resistor and a negative-side ground fault resistor on a secondary side of the voltage boosting circuit exceeds a positive potential of the DC power source and the capacitor is charged with reversed polarity by a secondary-side positive potential at the time of charging of the capacitor using the positive potential of the DC power source.

Abstract: In a method of determining interference in a capacitance sensor, a signal is transmitted on a transmitter sensor channel of the capacitive sensor. The signal is received on a receiver sensor channel of the capacitive sensor, the receiver sensor channel being coupled with an amplifier. Behavior of the amplifier is examined for non-linearity to determine if a level of interference has been received by the receiver sensor channel in conjunction with receipt of the signal.

Abstract: A capacitor capacitance diagnosis device includes a power supply which is for charging a capacitor, a discharge circuit which is connected to the capacitor in parallel to discharge energy of the capacitor, a resistance dividing circuit which is for measuring voltage drop value during discharging, a measurement circuit which measures divided voltage, and a diagnosis circuit which determines adequacy of capacitor capacitance from a time change in voltage due to the discharge. This makes it possible to diagnose adequacy of capacitor capacitance of an electric power apparatus during operation.

Abstract: An anti-pinch sensor, particularly for detecting an obstacle in the path of an actuating element of a motor vehicle is provided, having a sensor body, a measuring electrode, which is disposed in the sensor body and to which a measuring potential can be applied, a calibrating electrode, which is electrically disconnected and disposed in the sensor body adjacent to the measuring electrode, and a control unit. The control unit controls the measuring electrode and the calibrating electrode such that the measuring potential and the calibrating potential are equal in a measuring phase, and differ from each other in a calibrating phase.

Abstract: Systems and methods according to aspects of the present invention are described. The systems and methods enable charging, soaking, and measuring of capacitors to be conducted quickly. Charging and soaking typically occurs in parallel and certain embodiments facilitate the measuring of capacitor leakage by sequentially disconnecting each capacitor and measuring the time for voltage on the capacitor to reach a predetermined threshold. Further, all capacitors can be disconnected from a charging source simultaneously and voltages can be measured for each capacitor simultaneously. Monitoring can be periodic in nature. Substantial time savings in the calculation device of leakage values and parameters can be attained.

Abstract: A sensitivity analysis system has a memory device in which an interconnect structure data indicating an interconnect structure included in a semiconductor device is stored. The interconnect structure has: a main interconnection; and a contact structure electrically connected to the main interconnection and extending toward a semiconductor substrate. Parameters contribute to parasitic capacitance of the interconnect structure, and variation of each parameter from a design value caused by manufacturing variability is represented within a predetermined range.

Abstract: An apparatus for sensing a leakage current of a battery comprises a floating capacitor charged with a voltage detected from a cathode or anode terminal of a battery; a terminal selection switching unit for selecting a voltage detection path for the cathode or anode terminal; a charge switching unit for charging the floating capacitor with a detection voltage of the cathode or anode terminal, detected through the selected voltage detection path; a polarity reverse switching unit for reversing a polarity of the detection voltage of the anode terminal charged to the floating capacitor; and a leakage current determining unit for sensing the detection voltage of the cathode terminal charged to the floating capacitor and the polarity-reversed detection voltage of the anode terminal charged to the floating capacitor to calculate a leakage resistance, and comparing the calculated leakage resistance with a criterion insulation resistance to determine whether a leakage current occurs.

Abstract: Test structures and methods for measuring contact and via parasitic capacitance in an integrated circuit are provided. The accuracy of contact and via capacitance measurements are improved by eliminating not-to-be-measured capacitance from the measurement results. The capacitance is measured on a target test structure that has to-be-measured contact or via capacitance. Measurements are then repeated on a substantially similar reference test structure that is free of to-be-measured contact or via capacitances. By using the capacitance measurements of the two test structures, the to-be-measured contact and via capacitance can be calculated.

Abstract: A sensor system is provided having an at least partially magnetoelastic deformation element for measuring pressures, caused by a fluid, that are able to be applied to the magnetoelastic deformation element, having a magnetic circuit formed via a magnetic flux feedback and having a sensor unit and an evaluation unit. The sensor unit is positioned at the deformation element and the evaluation unit having an evaluation coil is structurally separated from, yet inductively coupled to the sensor unit. The sensor unit has a sensor coil positioned on the deformation element and the evaluation unit has the evaluation coil that is inductively coupled to the sensor coil, the sensor coil forms a resonant circuit, using its own parasitic capacitance or using an additional capacitance, which is able to be energized by the evaluation coil in free resonance with strong or weak inductive coupling by a magnetic circuit enclosing the two coils.

Abstract: Damage and usage conditions in the vicinity of fasteners in joined structures are nondestructively evaluated using the fasteners themselves. Sensors or sensor conductors are embedded in the fasteners or integrated within the fastener construct, either in the clearance gap between the fastener and the structure material or as an insert inside the shaft or pin of the fastener. The response of the material to an interrogating magnetic or electric field is then measured with drive and sense electrodes both incorporated into the fastener or with either drive or sense electrodes external to the fastener on the material surface. In another configuration, an electric current is applied to one or more fasteners and the electric potential is measured at locations typically between the driven electrodes applying the current. The potential is measured circumferentially around the fastener at locations on the material surface or across pairs of fasteners throughout or along the joint.

Abstract: A gate capacitance of a MOS transistor is determined by (a) measuring the gate capacitance and dissipation factor; (b) obtaining a channel resistance and a tunneling resistance; (c) setting an initial capacitance and an error dissipation factor; (d) calculating a direct dissipation factor using the channel resistance, the tunneling resistance, and the initial capacitance; (e) calculating a calculated dissipation factor using the error dissipation factor, the direct dissipation factor, and the measured dissipation factor; (f) calculating a calculated capacitance using the channel resistance, the tunneling resistance, the initial capacitance, the error dissipation factor, and the measured dissipation factor; and (g) detecting the initial capacitance as an accurate gate capacitance of the transistor if it is determined that the calculated capacitance is equal to the measured capacitance and the calculated dissipation factor is equal to the measured dissipation factor, and otherwise repeating steps (c) through (g

Abstract: 1. Method for testing the tightness of capacitive sensors 2.1. Known methods of seal testing cannot be used because of the extremely small volume of the sensor cavity or on wafer level. Other known methods of seal testing are only possible with high expenditure on safety because, for example, radio isotopes are used. 2.2. Method for testing the tightness of capacitive sensors arranged in a hermetically sealed enclosure, in which the processed sensors are arranged in the form of a wafer, wherein the already sawn wafer bearing the sensors is immersed in a test fluid under defined conditions, the capacitance of each sensor is then measured and compared with the capacitance of reference sensors. 2.3. The invention is especially suitable for testing the tightness of capacitive, hermetically sealed sensors.

Abstract: The present invention relates to a system for nulling drive feedthrough error in a sensor having first and second drive electrodes which impart vibratory motion to first and second proof masses in response to first and second opposite phase drive signals, and having first and second capacitances defined between the drive electrodes and their associated proof masses. A mismatch between the first and the second capacitance is measured. Drive feedthrough caused by the measured capacitance mismatch is nulled by adjusting the relative amplitudes of the first and second opposite phase drive signals, whereby the ratio of the amplitudes is proportional to the ratio of the first and second capacitances. A servo loop may adaptively effect the ratio of amplitudes.

Abstract: A method and an apparatus for measuring insulation resistance capable of removing the influences of piezoelectric noise which is occurring due to mechanical vibrations applied to an electronic component to measure the insulation resistance of the electronic component with high accuracy. In order to do so, a predetermined measured voltage is applied to the electronic component arranged in a position subjected to periodic mechanical vibrations from the outside to measure a current flowing through the electronic component. Then, the value of the measured current flowing through the electronic component is integrated over the period of the mechanical vibrations or over a time which is an integral multiple thereof. With this arrangement, a piezoelectric noise current can be cancelled and only a leakage current to be primarily measured can be extracted. Thus, by calculating the value of the insulation resistance from the value of the current, the insulation resistance can be detected with high accuracy.

Abstract: A method of calculating capacitance between conductive patterns of an integrated circuit (IC) by defining a mesh of nodes in a space between at least two electrodes, calculating the electric potential at each node, and then calculating the parasitic capacitance between the electrodes.

Abstract: In a method for judging the conformity or non-conformity of a capacitor from the charging characteristic at the time when a direct-current voltage is applied to the capacitor, a threshold current value I0 of the dielectric polarization component of the capacitor is determined in advance, an evaluation function n(t) is determined based on a logarithmic value of the difference between the measured charging current value m(t) of the capacitor and the threshold current value I0 or the difference between their logarithmic values, and the evaluation function n(t) is approximated to a quadratic curve. When the quadratic coefficient of the quadratic approximation equation has a plus sign the capacitor is judged to be non-conforming, and when the coefficient has a minus sign, the capacitor is conforming.

Abstract: A method and system for contact potential sensing of dielectric properties of a fluid. The method and system include a contact potential sensor, an open or closed loop for passing a fluid past the sensor, measuring a contact potential to characterize dielectric properties of the fluid and outputting the dielectric property information for analysis and response thereto.

Abstract: A test apparatus and method of testing a capacitor while it is still in-circuit incorporation a sequence of tests including a DC capacitance value measurement, a measurement of the DC current paths in parallel with the capacitor, a measurement of the equivalent series resistance of the capacitor, and an AC impedance measurement of the capacitor and its associated circuitry.

Abstract: First and second fixed electrodes are fixedly provided on a housing which is mounted on a surface whose inclination angle is to be detected. A rotatable electrode is inserted between these fixed electrodes, and this rotatable electrode is mounted on a shaft which is rotatably provided on the housing. The rotatable electrode is made to regularly face a constant direction with respect to the gravitational direction. The first fixed electrode has a central angle of 180.degree., for example, and is split into a first fixed split electrode member having a central angle of 60.degree. and a second fixed split electrode member having a central angle of 120.degree.. Wires are connected to the fixed split electrode members respectively, thereby taking out two series-connected capacitances which are formed by the respective ones of the first and second fixed split electrode members and the rotatable electrode. The second fixed electrode is structured similarly to the first fixed electrode.

Abstract: Apparatus is provided for continuously compensating for the dielectric absorption effect in a measuring capacitor in a circuit which employs means for charging the capacitor to develop an output signal thereacross and wherein the absorption effect causes an error in the output signal following a charging interval. The dielectric absorption effect is represented by at least one impedance branch connected in parallel with the capacitor and this branch includes a resistor and a capacitor connected together in series and having a RC time constant. Compensating means is provided having a correction means associated with the impedance branch and wherein the correction means continuously receives the output signal and provides therefrom a compensating signal. The correction means has a time constant that corresponds with that of the associated impedance branch. The compensating signal is combined with the output signal to provide a compensated output signal.

Abstract: A contactless sheet resistance measurement apparatus and a method for measuring the sheet resistance of a desired layer of a first conductivity type, formed upon a substrate of an opposite conductivity type, is disclosed. The apparatus comprises a junction capacitance establishing means, a point location alternating current AC photovoltage generating means for generating a laterally propagated AC photovoltage, an attenuation and phase shift monitoring means for monitoring the .laterally propagated AC photovoltage, and a sheet resistance signal generating means responsive to the-junction capacitance establishing means, the AC photovoltage generating means, and the attenuation and phase shift monitoring means for generating an output signal indicative of a sheet resistance R.sub.S of the desired layer according to a prescribed sheet resistance model.

Abstract: A defibfillator has a self healing storage capacitor connected in parallel with a safety resistor, and a microcontroller. Upon receipt of a calibration request, the microcontroller charges the capacitor to a charging voltage greater than a starting voltage, then discharges the capacitor through the safety resistor. As the capacitor is discharging, the microcontroller continuously measures the voltage across the capacitor. When the microcontroller detects that the voltage across the capacitor is less than or equal to a starting voltage, a timer in the microcontroller is started. When the microcontroller detects that the voltage across the capacitor is less than or equal to an ending voltage, the timer in the microcontroller is stopped. The microcontroller then determines an elapsed time between the time the timer was started and stopped. The microcontroller then calculates a capacitance value of the capacitor based on the starting voltage, the ending voltage, and the elapsed time.