Abstract: An integral electronic meter system diagnostics package including a microprocessor, storage memory, logic for automatically and periodically performing a pre-select series of system diagnostic tests, and recording any results which exceed predefined programmable thresholds, and display means for displaying error and/or diagnostic messages identifying selected diagnostic data and/or errors discovered in the meter tests during a predefined period.

Abstract: The invention relates to testing apparatus, such as the type known as a burn-in test socket for integrated circuit "chips", where the chips are essentially planar electronic devices having a plurality of chip leads or traces, laterally projecting therefrom, for electrical interconnection to complementary traces on a planar electronic device, such as a mother board, upon which the socket may be mounted, during testing. The socket comprises a frame member for mounting to the planar electronic device, where the frame member includes electrical means for engaging chip leads and applying electrical current thereto during testing. A second element of the socket is a two-piece, adjustable cover member consisting of first and second members floatably mounted together by plural compression springs, where the first and second members are axially movable relative to one another.

Abstract: A device (100) for use in a test fixture system which uses a plurality of ultrasonic transducers (103,105,107) to transfer energy to a plurality of contact probes (109). The ultrasonic energy enables the pins (111) to pierce and move obstructing materials to insure adequate electrical contact between the contact probe and an electrical connector on a device under test.

Abstract: An integral electronic meter system diagnostics package including a microprocessor, storage memory, logic for automatically and periodically performing a pre-select series of system diagnostic tests, and recording any results which exceed predefined programmable thresholds, and display means for displaying error and/or diagnostic messages identifying selected diagnostic data and/or errors discovered in the meter tests during a predefined period.

Abstract: The present invention provides a connector inspecting apparatus (D1, D2, D3, D4) for inspecting a connector having a retainer (R1, R2, R3, R4) for positioning and fixing a plurality of terminal metal fittings to predetermined positions in a housing (H1, H2, H3, H4). A receiving portion (40) for receiving the housing (H1, H2, H3, H4) of the connector (C1, C2, C3, C4) has a size regulating member (60) adapted to come in contact with the retainer (R1, R2, R3, R4) for positioning the housing (H1, H2, H3, H4) at the time of inspection.

Abstract: An integrated device test system (10, 40) having AC and DC measurement modes of operation comprises a drive circuit (11, 41), a programmable measurement unit (12) and a switch (18). The drive circuit (11, 41) may be a current mode drive circuit (11) or a voltage mode drive circuit (41). The drive circuit (11, 41) is coupled to the programmable measurement unit (12) and a device under test (64). In a DC mode of operation, the switch (18) is configured to couple a sense terminal (39) with one end of an isolation resistor (66). A second end of the isolation resistor (66) is connected to a pin (63) of the device under test (64). In an AC mode of operation, the switch (18) is configured to couple the sense terminal (39) with the drive circuit (11, 41) and the force terminal (35) of the programmable measurement unit (12).

Abstract: A fiber optic, Faraday-effect sensing coil has very low linear and circular birefringence, which remains stable over a wide range of temperatures. The coil is fabricated from a spun fiber having an effective linear beat length of 100 meters or more, and is annealed after being formed into the coil. The coil has improved discrimination for magnetic fields associated with electric current-carrying cables, and may be incorporated into an optical current transducer (OCT), either interferometric or polarimetric.

Abstract: Disclosed is a measuring apparatus in which electrical characteristics of electronic parts can be measured in a substantially reduced measurement time. The measuring apparatus includes a tray for mounting a plurality of the electronic parts, a measuring mechanism having a plurality of measuring terminals positioned in accordance with the respective positions of the electrodes in the plurality of electronic parts mounted on the tray, and a drive mechanism for moving the tray and the measuring mechanism relative to each other to thereby cause the respective electrodes of the electronic parts mounted on the tray engage the corresponding measuring terminals in the measuring mechanism.

Abstract: A current sensor for measuring a primary electrical current inducing a primary magnetic field defined over a known region includes a first sensor unit for measuring the line integral of the primary magnetic field along a first predetermined path included within the known region; and a second sensor unit for measuring the line integral of the primary magnetic field along a second predetermined path within the known region, the line integral of the primary magnetic field measured by the second sensor unit being a predetermined calibrated amount different from the line integral of the primary magnetic field measured by the first sensor unit. The current sensor further includes a current source for generating a current inducing a magnetic field to partially offset the difference between the line integral of the primary magnetic field measured by the first sensor unit and the line integral of the primary magnetic field measured by the second sensor unit.

Abstract: A test probe including a flexible membrane (12) having an array of test probe contacts (14) capable of softly and gently contacting pads on a device under test is provided with a structure that effectively applies tension to the membrane while at the same time automatically leveling the membrane and removing distortions. A small pressure plate (30) is bonded to the inner surface of the membrane behind the test probe contacts. A pressure post (58) having a pointed or rounded end (64) is pressed against the pressure plate (30a) and makes pivotal contact with the plate. A spring (50) including an adjustment screw (56) that axially adjusts the compression of the spring, applies pressure through the pivot point to the pressure plate and thus to the membrane at its test probe contacts.

Abstract: An assembly suitable for use as an overclamp assembly is provided. The assembly includes a base having a shaft inserted therethrough. The shaft rotates about an axis relative to the base. A center block is pivotably coupled to the shaft for arcuate movement about the axis and relative to the base. A longitudinal drive assembly is inserted into the center block and coupled to the shaft. Rotation of the shaft causes the longitudinal drive assembly to traverse a longitudinal path and an arcuate path about the axis. The longitudinal drive assembly includes a holder which is suitable for attachment to a probe arm.

Abstract: A test fixture is provided for testing electrical characteristics associated with a printed circuit board (PCB). Spaced-apart solenoids each have an extendible arm aligned along an axis defined by a connector assembly on the PCB to be tested. The arms are located to have sufficient travel to engage the side of the connector assembly. A mechanism is provided which detects which of the arms engage the connector assembly. Arm engagement data is stored in memory of a PC for type of connector assembly to be tested by the apparatus. A mechanism is provided for determining if a correct test program has been selected by a user for testing a particular connector assembly based on whether the arm engagement data matches the arms that engage the connector assembly.

Abstract: An alternating current sensor for measuring a primary alternating current inducing a magnetic flux density defined over a known region comprises: a first sensor for measuring changes in magnetic flux due to the primary current over a first predetermined area included within the known region; a second sensor for measuring changes in magnetic flux due to the primary current over a second predetermined area within the known region, the changes in magnetic flux measured by the second sensor being a predetermined amount different from the changes in magnetic flux measured by the first sensor; and a current source for generating a current inducing changes in magnetic flux over a third predetermined area to offset the difference between the changes in magnetic flux measured by the first sensor and the changes in magnetic flux measured by the second sensor.

Abstract: The present invention provides an electro-optical element arranged to face a liquid crystal base plate, an electric source to impress an electric voltage between them, a source of light for irradiating light on the electro-optical element, a light detector to receive the reflected light from the electro-optical element, and a mounting device for fixing the liquid crystal base plate in a fixed position. The mounting device has a highly flat surface, groove thereon and vacuum attaches the liquid crystal base plate on the surface of the base platform. Light irradiates a reflective layer located on the lower surface of an electro-optical element which is in close proximity to the liquid crystal display base plate. A voltage is applied across the electro-optical element and the light reflected by the electro-optical element are measured. The optical characteristics of the electro-optical element is measured.

Abstract: The present invention performs RF performance measurements on basic transistors of a microwave monolithic integrated circuit while it is being fabricated. The circuitry necessary to assess the performance potential at the frequency and power levels of interest is provided by incorporating matching elements onto RF probes used for in-process tests. This invention measures the RF performance potential of GaAs monolithic microwave integrated circuits at an early stage in the process before expensive process sequence has been completed. The essence of the invention is that the transistors are measured with an RF probe that has RF matching circuitry included as an integral part of the probe. Consequently, the performance potential of circuits on the wafer is assessed at the earliest possible point in the manufacturing process; specifically as soon as Schottky barrier gates have been deposited. This in-process measurement approach may be applied to any microwave monolithic integrated circuit.

Abstract: An alternating current sensor employing a mutually-inductive current sensing scheme comprises a conductive pipe and a cylindrical-shaped conductive element at least partially surrounded by the pipe. The pipe is substantially concentric to the conductive element and a conductor electrically connects a pair of corresponding ends of the pipe and conductive element to form a connected conductive path through the sensor. The conductive element may include a passage or opening shaped to form a magnetic field within the passage during current flow along the conductive path.

Abstract: A meter measures a voltage across a quasi-diode, the voltage caused by a current flowing through a resistance which changes substantially exponentially with changes in a medium being sensed. The meter comprises a logarithmic current measuring circuit coupled to the resistance to provide a measurement output that is a logarithmic function of the current flowing through the sensing resistance. A switchable current source is controlled by a switching circuit to repetitively output first and second current values. A reference logarithmic circuit is connected to the switchable current source and is physically coupled to the logarithmic measuring circuit so as to be maintained at a substantially equal temperature value. The logarithmic reference circuit manifests a first voltage in response to the first current value and a second voltage in response to the second current value, both voltage values dependent upon the temperature of the logarithmic reference circuit.

Abstract: A spring probe (pogo pin) contactor for testing PGA (Pin Grid Array) devices that limits compression of pogo pins within the spring probe contactor is disclosed. A PGA device has a plurality of device pins extending therefrom for insertion into the spring probe contactor in order to test the PGA device. At least one device pin of the plurality of device pins is provided with a widened annular portion expanding from a portion of the one device pin. A surface of the spring probe contactor has an array of apertures for receiving each device pin of the plurality of device pins of the PGA device in order to make contact with and compress the pogo pins. A cavity is coupled to the surface of the spring probe contactor which corresponds to and mates with the widened annular portion of the one device pin in order to limit an amount of insertion of the PGA device, thereby limiting the compression of the pogo pins.

Abstract: A circuit board extractor particularly suitable for extracting "burn-in" boards from a test fixture is attached to the front of the test fixture between the tester connector assembly and the burn-in board, or burn-in board frame rails, for movement of a movable member between first and second positions. The first position of the movable member occurs when the pin connectors on the edge of the burn-in board are inserted into corresponding pin receptacles on the front of the test fixture. Movement of the movable member from the first position thereof to its second position pushes the burn-in board away from the front of the test fixture to cause withdrawal of the pin connectors on the edge of the burn-in board from the pin receptacles on the edge of the test fixture without damaging the burn-in board or the test fixture.

Abstract: A semiconductor apparatus for functionally inspecting semiconductor devices is designed to prevent contact failure, deformation, and the like caused by solder transferred from external leads of semiconductor devices and deposited on contact terminals of the inspection apparatus. A sheet having metal-film patterns corresponding to an array of external leads of a semiconductor device is interposed between the external leads and the contact terminals to electrically connect the external leads to the contact terminals. The semiconductor device is inspected and the sheet is changed at a suitable time when it is contaminated with solder.