Abstract: A voltage regulator formed on an integrated circuit is provided that includes an amplifier and a feedback circuit. The amplifier is operable to receive a reference voltage and a feedback voltage. The amplifier is also operable to generate a regulated output voltage based on the reference voltage and the feedback voltage. The feedback circuit, which is coupled to the amplifier, is operable to generate the feedback voltage. The feedback circuit includes an inductor-capacitor network. The inductor-capacitor network is operable to remove high frequencies from the output voltage.

Abstract: A current source with low temperature dependence includes a reference current source and a current mirror for copying the reference source current to at least one output branch. The reference current source and the current mirror may have opposite coefficients of temperature dependence and the current mirror may be a weighted mirror. The present invention is particularly applicable to the manufacture of integrated circuits.

Abstract: The invention is a multipath meter that analyses estimates of parameters associated with a direct signal component and one or more multipath signal components of a signal received by an antenna. The meter analyses the parameter estimates in order to facilitate the select of a location for an antenna, monitor signal quality at an existing antenna site, and/or to determine if satellite failure or some other type of signal failure has occurred. The multipath meter makes available to a user or for analysis information related to the contributions of the direct signal and the multipath signals to the received signal. The information includes estimates of various parameters such as delay, relative amplitude and phase of the direct and multipath signals. The meter calculates a ratio of the amplitudes of the direct and the multipath signals, to determine the severity of the multipath signals and, thus, the signal quality.

Abstract: A method for measuring the waveform of light is provided, which makes it possible to synchronize easily the phase of sampling light with the phase of target light even if the target light is ultra-high speed pulsed light and is transmitted by way of long transmission channel, and to measure the waveform of target light with sufficient time resolution in real time. The method comprises the steps of: (a) generating sampling light having a pulse width sufficiently narrower than that of the target light from the target light; a repetition frequency of the sampling light having a constant difference with respect to a repetition frequency of the target light; (b) supplying the sampling light and the target light to a nonlinear optical member to generate cross-correlated light between the sampling light and the target light; and (c) measuring waveform of the target light based on the cross-correlated light.

Abstract: The present invention relates to a high speed sample and hold circuit having a plurality of sample and hold subcircuits coupled in parallel between an input and an output. The circuit also having a calibration sample and hold subcircuit coupled to the plurality of sample and hold subcircuits. The calibration circuit is operable to modify a timing for one or more of the plurality of sample and hold subcircuits to thereby reduce sampling mismatch between the plurality of sample and hold subcircuits. The present invention also having a method of reducing timing mismatch in a high speed, parallel coupled sample and hold circuit.

Abstract: An apparatus for detecting shaking of stroke of a linear compressor and a method are provided. A linear compressor mis-operates due to change in an external voltage or noise because the shaking of the stroke is detected by the amounts of change in the stroke or current.

Abstract: The present invention is a power monitoring circuit for sensing line conditions in a three phase power line. In the circuit a plurality of series connected power supplies for powering various components of the circuit are connected in series with a current sensing element for sensing current supplied to the power supplies. The power supply and current sensing element arrangement, in turn, is connected across a three phase bridge rectifier, which is in communication with the three phase power supply line. A circuit analyzer in communication with the current sensing element senses unbalanced line conditions based at least in part on a signal developed by the current sensing element. Preferably, the circuit further includes a three voltage reducing resistors interposed between the three phase power line and the bridge rectifier for reducing the voltage stresses encountered by the circuit's components.

Abstract: A clamp for measuring an electric current flowing in conductors, the clamp comprising first and second jaws (1, 2) interconnected by a hinge axis (3) to be movable between a closed position and an open position, the jaws being provided respectively with first and second annular magnetic circuit segments (4, 5), each segment (4, 5) having a proximal end (7, 8) and a distal end (9, 10) relative to the hinge, and at least the first segment (5) being mounted to rock about a rocker axis (6) parallel to a hinge axis (3), the clamp including spacer means (12) for spacing the proximal ends (7, 8) apart, which spacer means are active at least when the distal ends (9, 10) are spaced apart by a distance that is greater than or equal to a predetermined safety distance.

Abstract: In a horizontal carriage type auto handler, it is possible to identify a carrier efficiently without stopping the carrier when reading the carrier identification information provided in the carrier for transferring a device and to reduce the number of sensors for reading identification information. A plurality of timing holes and data holes are provided in the carrier as identification information. The carrier is detected when a timing hole detection sensor and a data hole detection sensor detect the timing holes and the data holes.

Abstract: A method and apparatus for non-contact testing of a rotating shaft includes first and second proximity sensors coupled to an automated shaft testing system. Output signals from the proximity sensors are compared to empirically determined threshold values to determine the presence or absence of a shaft coupling characteristic, the speed of the rotating shaft, and the direction of rotation of the shaft when the shaft is oriented proximally to the sensors.

Abstract: A rotation detecting device has various portions that are covered with a resin-molded section. After integrally molding the first and second cores 8 and 9, permanent magnet 10, and terminal 14 within a resin-molded section 11, a coil 12 is wound in a slot section 11a formed in the resin-molded section 11. Then, of the resin-molded section 11, the coil 12 and the terminal 14 are electrically connected in a recess formed at an outer periphery of the resin-molded section. Accordingly, the coil 12 is not liable to be damaged by a contact of a high-temperature, high-pressure resin during the molding process.

Abstract: A sensing system for measuring the angular displacement of a rotating shaft is disclosed. The sensing system comprises a rotor and a sensor assembly disposed within the rotor. The rotor is constructed and arranged to be securably mounted to the shaft such that the rotor rotates in concert with the shaft. Furthermore, the rotor defines a plurality of teeth extending radially inwardly towards a center of the shaft. The sensor assembly comprises a sensor housing and a magnet arrangement disposed within the housing. The magnet arrangement defines a magnetic flux path between the sensor assembly and the rotor. As a result, the magnet arrangement and the rotor cooperate to define a magnetic circuit. Changes in magnetic flux through the magnetic circuit can be measured to determine the angular displacement of the rotating shaft.

Abstract: A position transducer includes a bias circuit that drives and controls first and second bias coils. The bias circuit monitors the value of a voltage produced in a second sensor coil and drives and controls the first and second bias coils such that the value of the voltage produced in the second sensor coil is always equal to a desired voltage value.

Abstract: The invention relates to a method for substantially temperature-independent detection of the position of a moving element (9) by way of an inductive position sensor (1), comprising a coil (5) and a core (4) movable within the coil, the position of said core in relation to the coil (5) being dependent on the position of said element (9), whereby a measurement of the inductance of said coil (5), corresponding to the core (4) position, is detected by connecting a voltage to said coil (5) and measuring the time period in which a current (i) through the coil (5) is changed between two predetermined levels. The method follows the steps of feeding a regularly alternating voltage to the coil (5), measuring the current (i) flowing through the coil (5), measuring the period of time (t1) needed for the current (i) to change from a first predetermined level (i1) to a second predetermined level (i2), and determining a measurement of the core (4) position through measuring the period of time (t1).

Abstract: The invention relates to a device for detecting the angle position of the steering wheel of a motor vehicle. The aim of the invention is to provide a device of this kind in which the technical problem of determining the absolute angle position of the steering wheel in a measuring range greater than 360° is solved without the need for mechanical reduction gears and such like. This is achieved by means of a measurement system comprising at least one coil system which cooperates with an electrically conductive structure configured on/in a flexible flat cable (6). The flexible flat cable (6) is wound in a winding gap situated between the outer lateral surface (3) of an inner cylindrical rotor (1) joined to the steering gear shaft and the inner lateral surface (4) of an outer cylindrical stator (2) joined to the steering column, in such a way that its one end is fixed to the rotor (1) and its other to the stator (2).

Abstract: The invention relates to measurement technology and can find application for nondestructive testing electrically conducting and/or ferromagnetic materials and products. The differential eddy-current transducer comprises a primary detector (1) which incorporates two similar search coils (2, 3) and an additional coil (4) having its leads connected in series aiding to respective first leads of the search coils (2, 3) to second leads of which voltage is applied in antiphase. The transducer further comprises an electronic unit (5) which is electrically connected to the primary detector (1) and incorporates a potentiometer (6), a capacitive element (7), and an operational amplifier (8). Two leads of the potentiometer (6) are connected to common connection points of the leads of the search coils (2, 3), and its midpoint lead is connected to the capacitive element (7) which in turn is connected to the inverting input of the operational amplifier (8) whose noninverting input is grounded.

Abstract: The invention concerns a method and apparatus for determining the hydride content in an electrically conductive substrate by generating a first electromagnetic alternating field that at least partly penetrates the substrate which in turn produces a second alternating field that reacts with the first field. The first field is set at at least two different frequencies and measurement at the frequencies of the combined alternating field formed by the interaction of the first and second fields determines the hydride content in the substrate.

Abstract: The inductive sensor arrangement for detecting metal objects hidden in a surrounding medium comprises a pair of field coils for generating an alternating magnetic flux by a sequential excitation with an AC-current and a pair of sense coils respectively mounted inside each associated field coil in an orientation to the axes of each of said field coils such that essentially no voltage is induced in said sensor coils in an environment free of a metallic object. If a metallic object comes into the vicinity of the inductive sensor four characteristic voltage value sets are produced by the sense coil pair which become subject of an algorithmic processing for defining a position and distinction criterion in respect to said hidden metallic object. The sensor arrangement has the advantage of a single point measurement resulting in an accurate position discrimination for a hidden metallic object like a rebar in concrete.

Abstract: Apparatus for detecting a metal object comprises a transmitter for generating a pulsed or an alternating magnetic field in the vicinity of the metal object to be detected and a detector for detecting the secondary magnetic field induced in the metal object by the transmitted magnetic field. The detector measures at least three magnetic field gradient components of at least first order of the secondary magnetic field. The apparatus also comprises a processor for determining at least one of the position or the electro-magnetic cross-section or an estimate of the shape of the metal object from the measured magnetic field spatial gradient components. The processor fits the measured components to dipole, multiple dipole, multipole, or extended source models. In a preferred embodiment, the invention may comprise three or more pairs of gradiometric coils, or other sensing means.

Abstract: Disclosed is a method for achieving miniature fluxgate circuits capable of remotely sensing local dynamic magnetic fields. By synchronizing the excitation currents of the sensor core with the time-varying magnetic signals, the sensitivity can thus be improved, thereby enabling dynamic measurements at high speed. Also disclosed is a magnetic recording head device which uses a fluxgate magnetometer to measure a sequence of magnetic digital data bits, capable of providing dual reading and writing functions at high speeds, whose fabrication is fully compatible with the current printing circuit technologies.

Abstract: It is an object of the present invention to provide a magnetic sensor which is suitable to be manufactured in a large amount, has a high sensitivity, and is easy to handle. A first outer layer section A is formed by laminating a plurality of magnetic sheets one upon another. A coil section is formed by laminating a plurality of coil-patterned sheets one upon another. A second outer layer section is formed by laminating a plurality of magnetic sheets one upon another. Each of the sheets forming the coil section B has its central portion formed by an elliptical magnetic body and its surrounding portion formed by a non-magnetic body on which a coil pattern is formed by a film located on the non-magnetic body.

Abstract: An method and system are disclosed for NMR echo-train data acquisition and processing for enhanced vertical resolution for a given signal to noise ratio. In one aspect, the method is based on providing an estimate of non-formation signal components and removing the estimate from the NMR signals. Computation of the estimate is done from the data itself or using a direct measurement of non-formation signals. In another aspect, the functions of reducing coherent noise components is separated from the function of reducing the random noise components, to enhance the resolution of the NMR pulse echo data for a given signal to noise ratio (SNR) of the data. Combination processing is disclosed, which enables efficient filtering of the input NMR data for both relatively high and relatively low SNR of the formation data.

Abstract: In a multi-shot MR imaging method, a navigator echo V(kx, n) of which phase-encoding amount is 0 is generated by applying a gradient magnetic field pulse in a readout direction (x-direction) and collected at each segment. A phase shift map C(kx, n) of V(kx, n) collected in the n-th segment is produced in k-space as a function in kx-direction with V(kx, 1) collected in the first segment being the reference. Next, noises are removed from C(kx, n), and C(kx, n) is smoothed. Then, an image echo signal S(kx, n, m) collected in the n-th segment is corrected in k-space according to a smoothed phase shift map C′(kx, n) of V(kx, n) collected in the same segment, and an image echo signal S′(kx, n, m) of which phase shifts are corrected is thereby acquired. Thus, the phase shifts of the image echo signals caused by a motion in the x-direction of a patient can be precisely corrected at a high speed.

Abstract: A main magnet assembly (12) creates a main magnetic field (Bo) through an imaging region (10). An operator selects sizes and locations of at least two intersecting slabs (72, 74) in a region of interest. A sequence controller (42) includes a gradient synthesizer (44) and an RF pulse synthesizer (46) that synthesize slab select gradient field pulses (80, 82) and magnetization tipping RF pulses (&agr;, &bgr;) to tip or rotate the magnetization in the slabs and an intersection region (70). A first RF pulse (&agr;) and slab select gradient tip the magnetization in the first slab and the intersection region out of alignment with the (Bo) field (FIGS. 5A, 7A). A second RF pulse (&bgr;) and slab select gradient tip the magnetization in the second slab out of alignment with the (Bo) field (FIG. 6B) and further manipulate the magnetization in the intersection region (FIG. 7B).

Abstract: Gradient fields Gx=∂Bz/∂x etc. are generated in an MRI apparatus in order to indicate the position (x, y, z) of an object pixel to be imaged. In a known MRI system the x and y gradient fields are generated by a combination of four gradient coils, two of which are intended to receive the x and y gradient signals whereas the other two coils are intended to receive a mix of the x and y gradient signals in order to enable a simpler structure of the gradient coils and easier impedance matching. According to the invention, apart from the x, y and z gradient signals, other signals are applied to a conversion system (35) in order to realize the desired gradient fields but also to achieve degrees of freedom that can be used for optimizing system parameters such as heat dissipation or the uniformity of the distribution of power among the gradient amplifiers.

Abstract: A magnet for magnetic resonance imaging has an interior working space within the magnet frame sufficient to accommodate a physician and a patient. Because the physician is positioned inside the magnet frame, the physician has unimpeded access to the patient. Elements of the magnet frame desirably encompass a room, and the magnet frame may be concealed from view of a patient within the room. Preferred embodiments facilitate MRI imaged guided surgery and other procedures performed while the patient is being imaged, and minimize claustrophobia experienced by the patient.

Abstract: A device for measuring the filling level of a medium—for example hydrogen—in a storage container of a storage device—for example a tank system. To provide a simple and direct possible way of accurately determining the filling level of the storage container even without knowing the amount of medium already discharged or irrespective of uncontrollable losses, the device is designed as a measuring device for measuring the nuclear magnetic resonance of the medium located in the storage container. For this purpose, the device has a measuring head with, for example, a permanent magnet and a measuring coil, via which a static magnetic field and an electromagnetic alternating field are generated in the measuring head. The electromagnetic alternating field is generated in a transmitter, which is connected to the measuring head by a bridge circuit.

Abstract: In one embodiment the invention comprises a system for generating an image of an Earth formation surrounding a borehole penetrating the formation. Resistivity of the formation is measured using a DC measurement, and conductivity and resistivity of the formations is measured with a time domain signal or AC measurement. Acoustic velocity of the formation is also measured. The DC resistivity measurement, the conductivity measurement made with a time domain electromagnetic signal, the resistivity measurement made with a time domain electromagnetic signal and the acoustic velocity measurements are combined to generate the image of the Earth formation.

Abstract: A metal locating system includes a first transmitter unit and a second receiver detector unit for locating an under and above ground radio frequency driven element such as a pipe. The first unit is a radio frequency transmitter operating at radio frequencies and coupled to the driven element as a loss line antenna. The receiver second unit is a switched diversity antenna connected to a radio FM receiver and a differential phase detection system. When the first unit is driven by the driven element, the second unit is able to detect and trace the position of the driven element relative to the switched diversity antenna.

Abstract: A line tracer is disclosed comprising a transmitter for generating a signal in a target pipe, a cable set, a detector for amplifying the signal and filtering unwanted electronic noise, and a method for employing the line tracer. The transmitter further comprises a transmitter circuit board having a pulse generation circuit, a tone generation circuit and a transformer drive circuit. The transmitter circuit board is tuned to provide a pulse frequency of approximately 1.3 Hz and a tone rate of approximately 600 Hz. The detector further comprises a detector circuit board having a difference amplifier, a first high pass filter, a second high pass filter, a non-inverting amplifier, and a sensitivity meter. The detector circuit board is designed to amplify the detected signal and to achieve an attenuation of frequencies from 0 Hz to 400 Hz that is 80 dB/decade. The detector provides a visual indicator of signal strength.

Abstract: The invention concerns a method, a system and a device for producing, from a substance, electric signals characteristic of the biological activity of an active element contained in the substance. The method consists in: placing the substance in a zone subjected to a specific electric, magnetic and/or electromagnetic excitation field. The method further includes a step which consists in transforming the fields resulting form the interaction between the specific excitation filed and the substance, into signals, in particular electric signals, using a first transducer receiving the resulting fields.

Abstract: Methods and apparatus are disclosed for canceling or eliminating borehole eccentricity effects on a formation resistivity measurement obtained with transmitter and/or receiver antennas which are substantially time varying magnetic dipoles with their dipole moments aligned at an angle to the axis of the borehole. Various apparatus are configured with a plurality of antennas having tilted or transverse magnetic dipole moments, at least one current sensor, means for conducting alternating current through one or more of the antennas, and means for calculating a scaling factor from signal measurements and for scaling the alternating current with the factor. One method includes scaling an alternating current and passing said current through one or more antennas to obtain the resistivity measurement.

Abstract: A multiplex voltage measurement apparatus configured to detect the breakage of a line coupling a voltage detection terminal and an electric leakage detection circuit includes a multiplex voltage measurement section and an electric leakage detection circuit. The multiplex voltage measurement section is configured to measure the voltage of each of N serially connected voltage sources via (N+1) voltage detection terminals coupled to a capacitor. The electric leakage detection circuit is configured to measure an insulation impedance between the voltage sources and a chassis. A sample switch in the leakage detection circuit prevents the formation of a loop connecting the electric leakage detection circuit to the voltage measurement section in the event of a disconnection between a voltage detection terminal and the multiplex voltage measurement section, allowing the detection of such a disconnection.

Abstract: A method and apparatus for automated testing of a plurality of electrostatic discharge (ESD) devices on a wafer. The wafer has M padsets and N conductive pads on each padset, where m is at least 1, and n is at least 2, and each ESD device is conductively coupled to a unique plurality of pads of a padset of the M padsets. Testing sequences, under program control of a computer system, implement the testing of the ESD devices.

Abstract: A plasma density measuring method which includes producing a surface wave at an interface between a dielectric member and a plasma, and measuring at least one of a plasma density and a relative change in plasma density, on the basis of the surface wave. A plasma processing system including a container having a window, and for storing therein a gas introduced thereinto, a dielectric member for closing the window of the container, a plasma voltage source for applying a high frequency voltage through the dielectric member to produce a plasma by use of the gas inside the container, wherein a predetermined process is performed by use of the thus produced plasma, a detecting system for detecting an electric field intensity distribution of a surface wave propagated through the dielectric member, and a feedback system for feeding back the result of detection by the detecting system, to determine a processing condition for the process.

Abstract: In a method of measuring fuse resistance in a fuse array, the P-MOS switches used for row address are replaced by a pass-gate device comprising an N-MOS in parallel with a P-MOS, with a close to zero voltage drop. By this means a reduced power source current is applied across the fuse. The voltage drop is measured and the resistance obtained. Thus non-destructive testing is carried out as compared to destructive testing with the prior art method.

Abstract: An electromagnetic wave measurement system includes an electromagnetic wave emitting unit, measurement condition changing unit for changing a measurement condition, a control unit controlling the electromagnetic wave emitting unit and the measurement condition changing unit based on actual measurement data of the object electronic circuit, which data has previously been measured under a predetermined measurement condition, and measurement condition data of the predetermined measurement condition in such a manner that electromagnetic waves resembling those of the object electronic circuit is emitted from the electromagnetic wave emitting unit under the same condition as the predetermined measurement condition.

Abstract: A system for efficiently and cost effectively monitoring the status of the interface between two dissimilar media is provided. In a preferred embodiment, the system uses principles applied from the theory of time domain reflectometry (TDR), together with novel circuitry and low cost narrow band telemetry, to provide real time monitoring on a continuous basis, as needed. The circuitry involved permits operation of the system without relying on relative values of signal amplitude while employing a novel feedback function that sets the pulse repetition frequency instantaneously to permit an optimum data collection rate as well as a separate measure of the status based on the system operating parameters. It has particular application to real time monitoring and alerting to the effect of scour events in waterways.

Abstract: A sensor for the capacitive measurement of film thicknesses, with a drum (10), which rolls along the film (12) and has at least one measuring capacitor (C1-C4), the plates of which are disposed in the peripheral surface of the drum (10), so that its capacitance is effected by the thickness of the firm, and with a transformer (26), for transmitting the measurement signal from the rotating drum (10) to the stationary part (28), where an oscillator (OSZ1-OSZ4), which is integrated in the drum (10), generates a frequency signal (24), which depends on the capacitance of the measuring capacitor (C1-C4).

Abstract: Useful in connection with IC testing at a post-manufacture stage, an example embodiment is directed to use of photoluminescence PL spectroscopy for detecting contaminants in circuit materials. According to one example embodiment, a system includes a test fixture arranged to secure a die and includes a laser-scanning microscope. This system is arranged to direct a laser beam at a target material in the die and receives a secondary PL component remitted from the target circuit material. A contaminant in the target material is indicated by the reception of the secondary PL component.

Abstract: A device including a probe plate including a plurality of test pins, a conductive layer disposed in proximity to the probe plate and including a plurality of openings therein corresponding the plurality of test pins and, an insulator layer disposed on the conductive layer and including a plurality of openings therein corresponding the plurality of test pins.

Abstract: A testing device for semiconductor components and a method of making the device is described. The testing device includes a support structure having an outer edge, and an adhesive film disposed on the support structure to hold a semiconductor wafer in position on the support structure so that neither the adhesive film nor the semiconductor wafer extends beyond the outer edge of the support structure.

Abstract: Testing systems are provided for testing a device under test (DUT), such as an integrated circuit. A preferred testing system includes a test array that incorporates a frame. The frame defines an aperture that is appropriately sized and shaped for receiving a DUT and mounts a testing probe that is adapted to extend into the aperture. The probe preferably is received within a recess formed along a bottom surface of the frame, thereby tending to enable the bottom surface of the frame to properly engage a surface to which it is to be mounted. Additionally, the probe may incorporate a configuration that tends to maintain the position of the probe relative to the frame and, thus, relative to the aperture. For instance, a shaped portion may be intermediately disposed along the length of the probe. So configured, when the shaped portion of the probe is received within a corresponding complimentary-shaped portion of its recess, the probe is substantially prevented from being urged along its longitudinal axis.

Abstract: An interface apparatus including a nesting member having a central test area, a positioning member surrounding the test area, and several removable adapters held by the positioning member to expose a selected portion of the test area. Each removable adapter includes a central opening that is sized to receive a corresponding ball grid array integrated circuits (BGA IC). During a first test procedure, a relatively small BGA IC is inserted through the relatively small central opening of a corresponding first adapter. The first adapter is then removed and replaced with a second adapter having a relatively large central opening. A second test procedure is then performed by inserting a relatively large BGA IC through the relatively large central opening formed in the second adapter.

Abstract: An apparatus for continuity testing of a pogo pin in a probe comprises a substrate having a pad, a power supply providing a voltage difference between the pad and the pogo pin, and a sensing device signaling when the substrate contacts the probe, and a current is generated by the connection of the pogo pin and the pad.

Abstract: Virtual device fixturing is used to test transistor products, such as LDMOS power amplifier products, in the final packaging and testing stage of device fabrication. The input and output impedance transformation networks of a typical test fixture are implemented in software. The impedance matching function, normally performed by the physical input and output impedance transformation networks of the fixture, is supplanted by de-embedded scatter parameter calibration files. Test equipment, such as a vector network analyzer, attaches to a universal test fixture, while the software scatter parameter components are responsible for making the calibrations necessary to present the device under test with a matching low impedance.

Abstract: A semiconductor device and a method for testing the semiconductor device of the present invention includes n macro blocks which process input data supplied from input terminals and output the data from output terminals, a test circuit which supplies test data for testing the macro blocks and receives the test data processed by the macro blocks in the test mode and a test path which supplies the test data from the test circuit to the input terminal of the macro block, supplies data of the output terminal of the k-th (k=1 to (n−1)) macro block to the input terminal of the macro block to the test circuit in the test mode. One macro block can be selected randomly to be tested.

Abstract: The present invention includes a driving circuit and method for driving signals. An input signal is received by the driving circuit on an input signal line which is connected to a bias circuit for a common voltage level. Two output lines from the driving circuit are driven to the receiver which is capable of using differential output lines or a selected single ended output line. Furthermore, the output lines may be driven to a high impedance selected by the voltage level of the input signal. The receiver of the output lines may be a SCSI device using multimode terminators which include low voltage differential and a single ended mode.

Abstract: An impedance compensation circuit and method for an input/output buffer provides dynamic impedance compensation by using programmable impedance arrays and a dynamically adjustable on-chip load. Accordingly, among other advantages, only a single off-chip or external calibrated impedance resistor is used and only a single test pad is necessary.

Abstract: An impedance controller comprises impedance control logic outputting an adjustable impedance and a comparator comparing the adjustable impedance with a reference voltage. The impedance control logic recalibrates said adjustable impedance only when said comparator indicates a change in impedance.