Abstract: A full Wheatstone bridge sensor has conditioning electronics of an ASIC connected thereto. Two independently controlled diagnostic switches (S1, S2) in the ASIC are commonly connected to one of the bridge output nodes. The first diagnostic switch connects first resistor between the bridge output node and bridge supply voltage and the second diagnostic switch connects a second resistor between the bridge output and bridge ground. The first diagnostic switch closes during a first diagnostic waveform phase and opens during all other phases of operation. The second diagnostic switch closes during a second and third waveform phase and opens during all other phases of operation. The diagnostic waveforms are used to test major signal conditioning and fault reporting paths of the ASIC.

Abstract: An apparatus for measuring thermal properties and making thermomechanical modifications on a material surface using a junction of different metallic wires. The junction of different metallic wires, defined as a Peltier tip, is distinguished from a conventional thermocouple by the fact that it works as a point heat source and as a point temperature sensor simultaneously when an electric current flows into the tip. This novel functionality of the Peltier tip offers a way to thermally characterize a material surface with submicron-scale spatial resolution and high sensitivity, while providing high spatial resolution and speed for thermal modifications since both heating and cooling are possible at the Peltier tip.

Abstract: A transmission electrode 10 and a detection electrode 12 are placed in an electrode section of a sensor and are capacity-coupled with a reception electrode placed on an opposed scale. Capacity change between the transmission electrode 10 and the reception electrode caused by displacement is detected with the detection electrode 12. A plurality of signals different in phase are supplied to the transmission electrode 10. The signal lines are wired like a zigzag using an upper layer and a lower layer and the distances between the signal lines and the detection electrode 12 are made substantially equal for making uniform the crosstalk amounts relative to the detection electrode 12.

Abstract: A circuit arrangement is described for compensating temperature non-linearity of the characteristics of piezoresistive, metallic or polycrystalline resistors (bridge resistors) connected in a bridge circuit, the non-linearities being caused by non-linearities of the resistors, in particular due to the physical quantities affecting the bridge circuit (temperature, pressure, bimetal effects, non-linear membrane stresses), and the resistors being composed of partial resistors having different temperature coefficients, with each of the partial resistors having a certain linear and non-linear temperature response. The partial resistors of each bridge resistor are selected on the basis of their known linear and non-linear temperature characteristics so that an asymmetric layout of the bridge circuit is obtained and a non-linear variation of a bridge output voltage of the circuit arrangement can be essentially compensated.

Abstract: A circuit capable of detecting natural gas at a wide range of concentrations is disclosed. The gas detection circuit includes a catalytic Wheatstone bridge circuit and an analyzing Wheatstone bridge circuit. A circuit for detecting natural gas, which includes placing a device containing the circuit described above in an area in which the air has a potential of containing natural gas, and monitoring the output signal for indications of the presence of natural gas is also disclosed.

Abstract: A pressure detecting bridge circuit produces a sensor signal Sd. A temperature detecting bridge circuit produces a temperature signal St. A reference voltage generating circuit produces a reference signal Sa. An analog multiplexer processes these signals Sd, St and Sa in a time-divisional manner. A differential amplification circuit and an A/D conversion circuit are commonly used to obtain the digital data corresponding to the sensor signal Sd, the temperature signal St and the reference signal Sa. The temperature detecting bridge circuit includes reference resistance elements. By adjusting the design resistance values of the reference resistance elements, the variation width of the sensor signal Sd in a pressure measuring range of the pressure detecting bridge circuit is substantially equalized in advance with the variation width of the temperature signal St in a temperature measuring range of the temperature detecting bridge circuit.

Abstract: The improved device for precise measurement of magnitudes includes a closed network circuit, an instrument for detecting malfunctions in the closed network circuit and means for outputting an indication of the balance of the closed network circuit. The closed network circuit includes a power source; a transducer in the form of a Wheatstone bridge that is defined by paired series resistors and defines a branch of the closed network circuit and the transducer is serially connected to the power source; and a resistive branch connected in series to the Wheatstone bridge. The instrument is connected to a first connecting point in the resistive branch and to second and third connecting points on the Wheatstone bridge. The instrument calculates a sum of the potential differences between the second and third connecting points and the first connecting point and outputs the summed potential differences.

Abstract: The improved device for precise measurement of magnitudes includes a closed network circuit, an instrument for detecting malfunctions in the closed network circuit and means for outputting an indication of the balance of the closed network circuit. The closed network circuit includes a power source; a transducer in the form of a Wheatstone bridge that is defined by paired series resistors and defines a branch of the closed network circuit and the transducer is serially connected to the power source; and a resistive branch connected in series to the Wheatstone bridge. The instrument is connected to a first connecting point in the resistive branch and to second and third connecting points on the Wheatstone bridge. The instrument calculates a sum of the potential differences between the second and third connecting points and the first connecting point and outputs the summed potential differences.

Abstract: A capacitance measuring device and method including ratio transformers, a reference capacitor(s), multiplying digital-to-analog converters connected to form a bridge, the converters being adjustable to at least partially balance the bridge, digital signal processor (DSP) for driving and control functions, and feedback to the DSP to maintain and to correct in real time desired amplitudes and phase relation of the signals produced by the ratio transformers. Commutation is used to balance or to average feedback signals to enhance precision, accuracy, resolution and stability. The bridge uses DSP generated phase shifted signals and reference capacitors to balance the real part of the unknown impedance.

Abstract: A linearization circuit includes a sensor circuit having a first terminal receiving an excitation voltage, and second and third terminals producing a sensor output voltage therebetween. A differential amplifier circuit produces a linearization current, and a scaling circuit operates to produce a scaled linearization current in response to the linearization current. A current direction switch circuit includes a fourth terminal receiving the scaled linearization current, a fifth terminal and conducting a correction current proportional to the linearization current, and a control terminal receiving a polarity control signal to determine the direction of flow of the correction current through the fifth terminal in response to the sensor output voltage.

Abstract: A main heater, auxiliary heater and guard heater arranged on an insulator substrate to absorb leakage current, thereby maintaining precise sensing temperature. The main heater is parallel with a bridge circuit containing the auxiliary heater, and the main and auxiliary heater s are typically adjacently arranged with a guard heater there between, electrically interconnected to maintain target temperature of the main heater, regardless of leakage current typically resultant from insulation substrate deterioration.

Abstract: Voltages and currents of electromagnetic interference developed in cables or the like electrically connected to pieces of electronic equipment are respectively measured by non-contact voltage probes and non-contact current probes both of which have double coaxial cylindrical type inner and outer electrodes and wherein the outer electrode is grounded and a voltage output under capacitive coupling is taken out from the inner electrode. An effective component of energy of each propagating electromagnetic interference is calculated from the result of the measurements. An invading route of each electromagnetic interference is specified from the magnitude of the energy and the direction in which the energy flows. While the pieces of electronic equipment are being placed under operating conditions, the behavior of the electromagnetic interference can be accurately recognized and the invading route of each electromagnetic interference can be quantitatively specified according to a physical quantity.

Abstract: A test circuit and method for determining the operating status of a coaxial cable, the coaxial cable including an internal conductor and an external conductor. The test circuit comprises a measurement terminal, a resistor coupled to the internal conductor adjacent a first end of the coaxial cable and the measurement terminal, a second resistor coupled to the internal conductor adjacent a second end of the coaxial cable and to a reference voltage, and a measurement device coupled to the measurement terminal for producing an output that is reflective of the operating status of the coaxial cable. In one embodiment, the measurement device comprises a voltage comparator logic output circuit. In another embodiment, the measurement device comprises an ohmmeter.

Abstract: A voltage tester has an indicator housing and two separate probes connected to the housing by lead wires. One or more visual indicators are provided on the top surface of the indicator housing which wrap around to the sides and front of the indicator housing, and the bottom of the indicator housing has a clip into which the probe handles may be snapped from the sides of the clip so as to hold the probes beneath the indicator housing with the probe tips extending forward of the indicator housing and spaced a distance apart so as to fit into the blade openings of an ordinary wall outlet.

Abstract: A connector testing system includes a bridge clip having a body and at least one test lead having a fixed end connected to the body and a free end having a projection formed thereon, and a connector having a top portion and a housing having at least one test channel therein. At least one terminal strip is disposed within the connector and a portion of the terminal strip is disposed within the at least one test channel. A flap is connected to the housing for sealing the at least one test channel when the flap is in a first position and for sealing the at least one test channel and securing the bridge clip to the connector at a second position.

Abstract: A probe card comprises the following elements. An insulation film is provided which is flexible and extends on a first surface of a substrate. The insulation film has a first surface in contact with the first surface of the substrate, to form a space region which is defined between the first surface of the substrate and the first surface of the insulation film so as to allow part of the insulation film to move into the space. Probe patterns extend on a second surface of the insulation film so that the probe patterns.

Abstract: This invention relates to an electric field sensor for near field measurement. The electric field sensor of the present invention uses both piezoelectric and converse piezoelectric resonances. Composed of no metallic parts, the probe of the sensor minimizes field disturbance. The most distinguished feature of this probe is that a signal is transmitted outside neither electrically nor optically, but mechanically.

Abstract: An electrical contact test probe for use in providing electrical continuity between diagnostic equipment and a test point of an electrical circuit under test is provided. The test probe includes an elongated plunger slidably mounted within an elongated tubular barrel and extending outwardly therefrom for contacting the test point of the circuit under test. A spring is seated in the barrel and is interposed between the barrel and the plunger for biasing the plunger axially and outwardly of the barrel. The barrel consists of an elongated body having an inner bore, a generally closed end, and an open end. The barrel also has at least one cantilevered tab struck from the body and having a free end projecting into the inner bore toward the generally closed end of the barrel. The tab is located on the barrel such that the free end engages a shoulder of the plunger when the plunger is in an extended position so as to prevent outward biasing of the plunger beyond the extended position.

Abstract: A tool for indicating the presence of potentially dangerous voltages to the user includes circuitry for detecting the presence of an AC voltage on a blade or other operative portion of the tool, circuitry for filtering and processing the detected AC voltage, and a display for indicating the detected AC voltage to the user.

Abstract: A probe tip for connecting an instrument to a circuit under test is disclosed. The probe tip is interchangeable with other probe tips to provide different attenuations of the signal under test to the instrument. The signal from the circuit under test is coupled to the instrument via a cable. The probe tips have a compensation network that cancels the effects of cable loss. The probe tips provide attenuation by using the probe tips internal impedance, and the characteristic impedance of the cable, to form a voltage divider.

Abstract: A scour probe assembly comprises an elongated rigid tubular member of eleically insulative material, an anchoring structure fixed to a distal end of the tubular member, and a signal transmission device mounted on the tubular member. A pair of substantially parallel electrically conductive sensor lines are fixed to an external wall of the tubular member and extend along at least a portion of an axial length of the tubular member from a closed proximal end toward the distal end and extend through the closed proximal end to an interior of the tubular member. Electronic components are disposed in the interior of the tubular member and are interposed between ends of the sensor lines in the interior of the tubular member and the signal transmission device mounted in the tubular member.

Abstract: An electrostatic discharge locating system may include a plurality of receivers and a central unit. Each receiver may include an antenna. The receivers may receive radio wave signals emanating from an electrostatic discharge event and transmit the signals to the central unit for processing. The central unit may determine the location of an electrostatic discharge event from the relative time of signal reception or the signal amplitudes along with predetermined locations of the receivers.

Abstract: An SWR bridge with an accompanying set of connector saving adapters for connecting between the test port of the SWR bridge and a test device. The SWR bridge includes a branch opposite the test port which has an impedance set to substantially compensate for the impedance of the connector saving adapters. The connector saving adapters are configured to mate with connectors from two groups of test device connectors in both male and female versions, a first group including 3.5 mm, SMA and 2.92 mm connectors, and a second group including 2.5 mm and 1.85 mm connectors. To compensate for any capacitive mismatch between an adapter configured for a particular group of connectors and a given connector type, either a center conductor pin setback, an inductive counter bore in the outer conductor of the adapter, or a combination of the center pin setback and inductive counter bore may be utilized.

Abstract: A contact device having a plurality of nominally coplanar first contact elements makes electrical contact with corresponding nominally coplanar second contact elements of an electronic device when the contact device and the electronic device are positioned so that the plane of the first contact elements is substantially parallel to the plane of the second contact elements and relative displacement of the devices is effected in a direction substantially perpendicular to the plane of the first contact elements and the plane of the second contact elements. The contact device comprises a stiff substrate having a major portion with fingers projecting therefrom in cantilever fashion, each finger having a proximal end at which it is connected to the major portion of the substrate and an opposite distal end and there being one or two contact elements on the distal end of each finger.

Abstract: A device for non-contact, non-invasive measurement of current or power in a wire, cable or conductor includes a small coil having multiple turns with a thin ferromagnetic strip. The coil may be secured to a wand or housing adapted to be used to place the coil in close proximity to the wire, cable or conductor, whereby a voltage is induced in the coil. An amplifier and or an analog or digital signal processor is utilized to increase sensitivity. A readout indicates the magnitude of the induced voltage, and a scaling device renders the readout display indicative of the current or power in the wire, cable, or conductor. The readout may comprise a digital display, a series of light emitting devices, an oscilloscope, a digital computer display system, or a flashing light emitting device having a flash rate proportional to the magnitude of the voltage. The device may be constructed in a wand or pen-like fashion, with the coil and strip incorporated into the wand.

Abstract: A probe unit comprises a support member having an edge extending in a first direction parallel to the surface of a plate-like test substance; and a plurality of needle-like probes disposed on the edge and extended in a third direction intersecting the first direction and a second direction perpendicular to the surface of the test substance. The plurality of probes are divided into at least a first group and a second group arranged at intervals in the second direction.

Abstract: According to the present invention, a main chuck, on which a wafer having a number of devices is held, is driven under the control of a computer, and the devices on the wafer are brought into electric contact with the probes arranged on the upper side of the main chuck. On the basis of outputs from the probes, a tester sequentially measures the electric characteristics of the devices.

Abstract: A measuring apparatus has a capacitor incorporated in a handy measuring tool electrically connected to a voltage meter, and a sharp leading end of the capacitor is brought into contact with a lead of a large scale integrated circuit device for accumulating movable electric charge induced in the presence of a charged insulating package into the capacitor so that the amount of the accumulated movable electric charge is calculated from a potential difference produced between electrodes of the capacitor.

Abstract: A circuit tester which allows the testing of electrical outlets, telephone circuits and light bulb sockets. The circuit tester is cylindrical with two circuit probes. The first probe is a conventional two-prong electrical plug and the second is a conventional male light bulb connector. A standard telephone jack socket is provided on the side of the cylinder.

Abstract: A non-contact probe provides information as to relative amplitudes of harmonics of a current or voltage waveform as well as total harmonic distortion. The probe includes a non-contact sensor with an amplifier coupled thereto. Output signals from the amplifier are digitized and analyzed in a programmed processor. Output from the processor provides a display of relative harmonic amplitudes as well as an indicator of total harmonic distortion.

Abstract: In an electroconductive contact unit including a pair of needle members projecting from either end of a holder arrangement, and an electroconductive compression coil spring interposed therebetween for resiliently urging the needle members away from each other, the compression coil spring comprises a normally wound segment and a coarsely wound segment. When the contact unit is applied to an object to be contacted, the adjacent turns of the coil wire of the normally wound segment are brought into contact with each other so that the electric path between the needle members is substantially straight along the length of the coil spring with the coarsely wound segment.

Abstract: A meter is mounted on the wrist of the user with a suitable strap while the active or positive probe from the meter extends through a probe holder on the finger of the user. The probe lead is fairly short extending from the meter, through the probe holder to project beyond the index or pointing finger. Two forms of holding the probe to the finger are illustrated. The other probe to ground or neutral is longer and provided with a contact clip. The invention frees both hands of the user or at least all of the fingers except the one used to point the probe. With the invention the meter is more effectively and economically used.

Abstract: A resilient connector uses a spring made from a cylindrical tube. The wall of the tube is cut in a helix along the central portion of the tube to form the spring. One or more plungers within the spring have a tip extending past a first end of the spring and a second end attached to the spring. Each plunger is a pin or a pair of coaxial conductors separated by a dielectric sheath. One of the coaxial conductors is a conductive layer on the sheath. A double ended connector uses a spring made as described above with a pair of plungers attached one each to each end of the spring.

Abstract: A wafer probe system includes a plurality of vertical-parallel probe pins having a spring formed in a center portion thereof to provide a contact force control area. The spring being formed according to a predetermined shape having a known stress-strain profile. In one embodiment, a first spring shape results in a probe tip contact force that is approximately constant after an initial vertical displacement of the probe tip. In an alternate embodiment, a second spring shape formed in the probe pin results in decreasing probe tip contact force with increasing vertical displacement of the probe tip. A canted probe tip end permits creation of an X-Y force component to facilitate penetration of the passivation layer. The canted tip portion also permits non-rotatable alignment of the probe pins in a probe card to thereby prevent contact of one probe pin with another.

Abstract: A fixture for carrying a neural probe. The fixture has a base with opposite forward and rear ends, the rear end having an engagement feature for engaging a micropositioner and the forward end having a receiving feature for receiving the semiconductor substrate base of the probe.

Abstract: Sensors for measuring the flow rate of a fluid and for monitoring heat transfer. An induction-heated temperature-responsive sensor in contact with and cooled by the fluid, changes temperature in proportion to the quantity of heat removed by the fluid thereby providing a basis for determining flow rate or heat transfer. A flow modulation method and apparatus for improving the precision of flow rate measurement is also presented.

Abstract: A non-contact voltage probe is used to measure the voltage of electromagnetic interference developed in a cable or the like electrically connected to pieces of electronic equipment. The non-contact voltage probe has double coaxial cylindrical-type inner and outer electrodes through which a cable or the like is passed. The inner electrode is electrically connected to a voltage detector, which measures the voltage induced by the capacitance between the inner electrode and the cable passing there through, and the outer electrode is grounded.

Abstract: Apparatus and a concomitant method for estimating voltage on a wafer located in a process chamber. A probe, attached externally to a wall of the process chamber, detects voltage levels generated by a plasma within said process chamber. A relationship between the detected plasma voltage level and the wafer voltage is determined.

Abstract: There are provided a test probe for a measuring instrument, and a tester incorporating the test probe. The test probe includes a probe, a lead wire, a grip and a lead wire-holding piece. A probe for being brought into contact with a measuring object has a proximal end. A lead wire has one end thereof connected to a main unit of the measuring instrument and the other end thereof connected to the probe. A grip protects a portion connecting the probe and the lead wire. The grip is engaged with the proximal end of the probe. A lead wire-holding piece fixedly holds a distal end of the covered portion of the lead. The grip has a retaining portion engaged with the lead wire-holding piece for preventing the lead wire from being drawn out from the grip. In another form, the test probe has a crimp contact for connecting the proximal end of the probe and an uncovered portion of the lead wire. The grip protects a portion connecting the probe and the lead wire, including the crimp contact.

Abstract: A tweezer probe comprises a pair of arms (10) each made of a multi-layer printed circuit board. The outer conductive layers (20, 32) on each arm are etched to form a shield region (36) and a tip contact (34). The tip contacts (34) are connected to inner conductive layers (24, 28) by through-hole plating, the inner layers being etched to form connector wires (40) extending along the length of the arms to a connector region where leads (8) are attached. The arms (10) are substantially rigidly mounted together, with an adjustment mechanism (14, 72, 74, 76) being provided to alter the angle between the arms, the tips being moveable towards each other against the bias provided by the inherent resilience of the arms.

Abstract: An interface having nine connections between a probe and test and measurement equipment includes a fixed voltage source located in the test and measurement equipment, which delivers through a first connection a positive fixed voltage, and through a second connection a negative fixed voltage. A voltage-programming resistor located in the probe produces a signal that is delivered from the probe through one of the connections to the equipment to control a programmed voltage source. The programmed voltage is delivered as a positive programmed voltage through one pin and as a negative programmed voltage through a second connection. A probe identification resistor is located in the probe. An ohmmeter in the equipment measures the resistance of the probe identification resistor through one of the connections.

Abstract: A contact making and breaking device improves the dielectric absorption property of capacitance between one signal wire brought out from a reed switch and an conductive casing. A low current measurement system using the contact making breaking device greatly shortens the measurement waiting time when low current is measured. The contact making and breaking device includes a reed switch with first and second signal wires brought out from either end, a conductive casing, and an insulating material formed between at least the first signal wire and the conductive casing. A tubular conductor is emplaced in the region in which the insulating material is formed and at least partially encloses the reed switch. The tubular conductor is connected to the first signal wire.

Abstract: Determining the location of an ESD event is achieved through the use of an envelope detector or absolute value comparator which identifies the arrival of an electromagnetic waveform generated by an ESD event at each of a plurality of antennas. Arrival times are compared to determine the location of the ESD event. A plurality of N antennas are employed, and each antenna is coupled to a corresponding envelope detector, threshold discriminator, switch, and register. The output of a clock is coupled to the switches, and a microprocessor is coupled to the registers. When an antenna receives a waveform corresponding to ESD, the envelope detector extracts an envelope signal related to the envelope of the waveform and couples the envelope signal to the threshold discriminator. When the envelope signal has a value above a specified threshold, the threshold discriminator sends a signal to latch the current count of the clock into the corresponding register.

Abstract: A multi-channel electromagnetically transparent voltage probe transmission link system for monitoring a plurality of voltage signals at a plurality of test points of a device under test that is subjected to a radiation field. Each channel includes two voltage probes, an electrical to optical signal transmitter, an optical signal transmission line and a receiver located out of the radiation field. The voltage probes contact and sense the voltage signals at the test point. The electrical to optical transmitters are removably mounted in a common base and are powered by either a common (or shared) power supply and/or by dedicated power supplies, such as rechargeable batteries. The receivers process the optical signals and provide display signals corresponding to the sensed voltage signal at the plurality test points for evaluating the effect of the test radiation field.

Abstract: A tweezer probe comprises a pair of arms (10) each made of a multi-layer printed circuit board. The outer conductive layers (20,32) on each arm are etched to form a shield region (36) and a tip contact (34). The tip contacts (34) are connected to inner conductive layers (24,28) by through-hole plating, the inner layers being etched to form connector wires (40) extending along the length of the arms to a connector region where leads (8) are attached. The arms (10) are substantially rigidly mounted together, with an adjustment mechanism (14,72,74,76) being provided to alter the angle between the arms, the tips being moveable towards each other against the bias provided by the inherent resilience of the arms.

Abstract: This invention is an inexpensive probe apparatus operating at high precision that can be used for both low-frequency and high-frequency measurements. A line with a first and second conductor is extended from a probe connected to a circuit component. A low-frequency or high-frequency device is alternately connected to the line. A third common conductor runs parallel to the aforementioned line and a resistor and capacitor is connected between the probe end of the aforementioned second conductor and the aforementioned common conductor.

Abstract: A shorting pad probe tip for a substrate tester includes a compliant mandrel, a flexible conductive sheet and a nest plate. The flexible conductive sheet is loosely wrapped around the compliant mandrel. The compliant mandrel and flexible conductive sheet are secured together to the supporting nest plate. At least one side of the flexible conductive sheet is electrically conductive such that when the probe tip is brought in contact with the substrate to be tested, I/O pads on the surface of the substrate become electrically connected. In one embodiment the flexible conductive sheet is metallized polyimide.

Abstract: A device for measuring residual stress in ferromagnetic and non-ferromagnetic metal objects. The device having four electrically identical induction coils which form a four terminal alternating current bridge circuit. There is a fine wire shield formed of fingers for shielding the coils from stray capacitance. The bridge having four coil terminals. Two diagonally opposite coil terminals are connected to a variable frequency constant voltage generator. The other two diagonally opposite coil terminals are connected to a low noise broad band preamplifier. The preamplifier amplifies any unbalance in the bridge. There is a double pole double throw switch connected to two coil terminals which are diagonally opposite each other. Connected to the preamplifier is an amplifier. The amplifier is connected to a phase detector which is connected to a computer. The phase detector detects in phase and quadrature component signals.

Abstract: The hand held circuit tester includes a hollow handle. A probe extends from one end of the handle. First and second leads extend from the other. An LED carrying circuit board is situated within the handle. One end of the circuit board is connected to the probe by a spring. The other end is connected to the leads. A "U" shaped collar is received within slots in the circuit board in a position perpendicular to the plane of the circuit board. The collar edge abuts the edge of one of the handle parts to stabilize the circuit board relative to the handle.

Abstract: A non-contact voltage tester has a self-test feature so that when a switch clip of the tester is actuated, light and sound indicator devices are energized to give a single blink and beep, respectively, following which the tester is ready for probing for a voltage. The light and sound indicator devices also indicate the presence of a voltage when the switch is actuated and a voltage is detected at the probe tip of the tester.