Abstract: A position detection unit generates a position detection value PFB that indicates the position of a control target. A temperature detection unit generates a temperature detection value that indicates the temperature. A correction unit corrects the position detection value PFB. A controller generates a control instruction value SREF such that the position detection value PFB_CMP subjected to the correction matches a position instruction value PREF that indicates the target position of the control target. A driver unit applies a driving signal that corresponds to the control instruction value SREF to an actuator. The correction unit corrects the position detection value PFB such that the relation between the position detection value PFB and the actual position exhibits linearity that is uniform independent of the temperature.

Abstract: The described techniques address issues associated with hybrid current or magnetic field sensors used to detect both low- and high-frequency magnetic field components. The hybrid sensor implements a DC component rejection path in the high-frequency magnetic field component path. Both digital and analog implementations are provided, each functioning to generate a DC component cancellation signal to at least partially cancel a DC component of a current signal generated via the high-frequency magnetic field component path. The hybrid sensor provides a high-bandwidth, high-accuracy, and low DC offset hybrid current solution that also eliminates the need for DC decoupling capacitors in the high-frequency path. A modification is also described for implementing a Sigma-Delta (??) quantization noise reduction path to reduce the quantization noise and to improve accuracy.

Abstract: A system comprises first and second Hall-effect sensors and an amplifier. The first Hall-effect sensor has a first bias current direction parallel to a first direction, a pair of first bias input terminals spaced along the first direction, and a pair of first sense output terminals spaced along an orthogonal second direction. The second Hall-effect sensor has a second bias current direction parallel to the second direction, a pair of second bias input terminals spaced along the second direction, and a pair of second sense output terminals connected out of phase with the first sense terminals. The amplifier has a pair of amplifier input terminals coupled to the first and second sense terminals.

Abstract: Disclosed herein are an offset compensation apparatus for a magnetic detection circuit, and a method thereof. The offset compensation apparatus includes: an amplifying unit amplifying an output voltage, and outputting the amplified voltages; an offset detection unit detecting an offset; a comparison unit determining whether or not the offset output from the offset detection unit is greater than a pre-set positive reference value or smaller than a pre-set negative reference value; a counter unit; and a current supply.

Abstract: A current amplifying element that operates at a higher speed than conventional semiconductor devices is provided. An input current flows through an input current path 60 in a direction X, and a magnetic field generated from a magnet 90 is applied in a direction Z which is perpendicular to the direction X. An output current path 70 is formed under the input current path 60 with an insulator 80 interposed therebetween. Since the direction in which an output current flows is perpendicular to both the input current and the magnetic field, the current is amplified by the galvanomagnetic effects produced by the input current and the magnetic field.

Abstract: A current amplifying element that operates at a higher speed than conventional semiconductor devices is provided. An input current flows through an input current path 60 in a direction X, and a magnetic field generated from a magnet 90 is applied in a direction Z which is perpendicular to the direction X. An output current path 70 is formed under the input current path 60 with an insulator 80 interposed therebetween. Since the direction in which an output current flows is perpendicular to both the input current and the magnetic field, the current is amplified by the galvanomagnetic effects produced by the input current and the magnetic field.

Abstract: A driving circuit includes a power supply, an input capacitor, a Hall sensor, a first amplifier, a second amplifier, a full-bridge driver circuit, and a first operational amplifier. The input capacitor is coupled to the power supply. The input end of the first amplifier and the second amplifier is coupled to the output end of the Hall sensor. The control end of the full-bridge driver circuit is coupled to the output end of the first amplifier and the output end of the second amplifier. The first operational amplifier includes a first input end for receiving a first reference voltage and a second input end coupled to the first output end of the full-bridge driver circuit.

Abstract: A chopper-stabilized amplifier has switching networks arranged to support a high frequency clocking signal and to provide a high common mode rejection and a high rejection of an offset component of an input signal. A magnetic field sensor includes a Hall effect element coupled to a modulation circuit. The modulation circuit provides a signal to the chopper-stabilized amplifier. The chopper-stabilized amplifier provides an output signal to a low pass filter, which provides an output signal from the magnetic field sensor.

Abstract: A chopper-stabilized amplifier has switching networks arranged to support a high frequency clocking signal and to provide a high common mode rejection and a high rejection of an offset component of an input signal. A magnetic field sensor includes a Hall effect element coupled to a modulation circuit. The modulation circuit provides a signal to the chopper-stabilized amplifier. The chopper-stabilized amplifier provides an output signal to a low pass filter, which provides an output signal from the magnetic field sensor.

Abstract: The modular measuring drive system can include a housing having a cavity and being sized and shaped to fit within a disk drive bay of a computer and a measuring device, disposed within the cavity of the housing, for providing a measurement value to the computer. The modular measuring drive system can also include a conduit having a first end, which provides an opening for fluid to pass, and a second end coupled to the measuring device, a data port coupled to the measuring device and configured to be coupled to the computer and a power supply port, coupled to the measuring device, capable of receiving power from a power supply.

Abstract: A plurality of bridge transducers are provided in a dual arrangement. An output terminal from each transducer is coupled to differential inputs of an amplifier. Each of the other outputs from the transducers are respectively coupled together and used to control a bias for dual active loads. The transducers may be implemented within monolithic silicon integrated circuits, using bipolar technology with Hall effect, magnetoresistive or piezoresistive sensing elements for the bridge. A single Hall effect transducer may be coupled to the inputs of the differential amplifier, and a center tap terminal used to control a bias for dual active loads.

Abstract: Two bridge type transducers are coupled in series with their outputs each driving one of a pair of differential amplifiers, with the outputs tied together in a push-pull configuration. In further embodiments, push-pull operation is obtained by matching amplifier gain components and using current mirrors. Lower voltage operation may be achieved by simple diode level shifting of the transducer outputs. In one embodiment, the transducers comprise Hall effect sensors.

Abstract: To measure the current consumption of a circuit device with a current measuring device, the circuit device being supplied by a current/voltage supply line device, as simply as possible without the need for additional measuring devices, an integrated circuit configuration includes integrating the circuit configuration, the current measuring device, and, also, the current/voltage supply line device in a common chip and forming the current measuring device with a Hall sensor device.

Abstract: An amplifier circuit with offset compensation is particularly suited for a Hall element. In addition to the useful signal demodulation that is normally present and connected downstream of an amplifier, an error signal demodulator provides an error signal demodulation. The measured signals that are tapped off at the Hall sensor are coupled out at the input or output of the amplifier, and a demodulated error signal is fed back to the input of the amplifier. This makes it possible to reduce the drive range of the amplifier. The amplifier circuit is suitable in particular for Hall sensors that are operated in chopped mode.

Abstract: A temperature-compensated current source energizes a Hall element. The current source includes a voltage divider across the DC voltage supply busses and a differential amplifier arranged as a voltage follower which develops the output voltage across a reference resistor, creating a reference current which is amplified to generate a Hall energizing current. This results in a Hall element gain which is controllable over temperature. The temperature coefficient of the resistor can be chosen to compensate for the sensitivity temperature coefficient of a Hall element powered by a constant current source. Additionally, the temperature coefficient of the resistor may be chosen to compensate for the temperature coefficient of a magnet used to generate the magnetic field which the Hall element is intended to detect. The magnitude of the Hall current, and thus the Hall element gain, is directly proportional to the magnitude of the DC voltage supply.

Abstract: A differential amplifier circuit suitable for amplifying a faint signal, such as the output of a magnetic sensor including a Hall element. The differential amplifier circuit includes switching units which are provided at the input and output terminals of a differential amplifier to switch the polarity of the input and output signals, and low pass filters which are provided at the output terminals to remove the switching frequency component from the output signal, thus working as an ideal amplifier with no offset voltage. Furthermore, by alternating the polarity of driving current of the Hall element for inverting the polarity of the input signal of the differential amplifier, an error voltage of the Hall element caused by location error of the output electrodes and the voltage drop across them can be eliminated at the same time.

Abstract: A self-adjusting single- or twin-tube shock absorber having a cylinder closed at both ends and filled with at least one damping medium, a piston rod sealingly inserted into the cylinder, and a piston carried on the cylinder side end of the piston rod for dividing a cylinder spaced into two half chambers. The piston rod has a longitudinal bore formed therein and at least one orifice traversing the longitudinal bore for connecting the two half chambers. An electrically controlled distributing slide valve device for opening and closing the orifice includes a slide valve sleeve coaxially surrounding the piston rod and the orifice and movable on the piston rod for opening and closing the orifice. A step motor has a slide valve as a movable part thereof for stepwise adjusting the slide valve and a stator including a plurality of exciter coils and coil formers surrounding the slide valve sleeve and the piston rod.

Abstract: An integrated circuit includes an epitaxial layer. In a near central region thereof is formed a symmetrical array of four equal sized Hall cells that are connected in parallel to form one Hall element. A moat surrounds the Hall element consisting of two concentric isolation walls separated by a band of opposite conductivity epitaxial material. The output of the Hall element is connected to the input of an adjacent differential amplifier that has two extraordinarily large amplifying transistors with emitter areas each equal to about a half of a Hall area, for achieving much better control over the relative dimensions of these emitters and thus over the amplifier offset voltage from chip to chip. The emitter resistors are likewise made very wide and both pairs of components are physically arranged to have balanced thermal coupling to the Hall element for further enhancing control of offset voltage.

Abstract: A silicon integrated circuit has a Hall-element, a differential amplifier and a Schmitt trigger circuit connected in tandem to form a Hall switch. It is demonstrated that only one set of component parameters, e.g. resistor values, exists that provides an optimally smooth temperature coefficient (TC) of Hall-switch operate-point. It is further shown that by adding an adjustable resistor from the Schmitt trigger circuit ground, which resistor has the same resistivity and TC as does the Hall element, adjustment of the operate-point to another particular operate-point is accomplished without substantially altering the above-noted optimum TC. Operate-point adjustment, e.g. by blowing fuse links, during manufacturing, at probe, can be effected to yield a narrow distribution of operate-points conforming to a customer specification.

Abstract: A two-lead Hall effect sensor (10) has a combined voltage supply and output terminal (12) and a ground or reference terminal (14). A Hall device (16), a comparator (18) and a voltage/current converter (20) are each connected between terminals (12) and (14). Hall device (16) supplies a first signal to comparator (18) when it senses a magnetic field strength above a predetermined amount, and supplies a second signal in the absence of the magnetic field strength. Comparator (18) in turn supplies either a first voltage state or a second voltage state to the converter (20). Converter (20) converts the first voltage state into a first current appearing at terminal (12), indicating the sensing of a magnetic field, and similarly converts the second voltage state to a second current, indicating a weak or absent magnetic field.

Abstract: Circuit for enhancing the utilizable Hall signal of a Hall sensor, including N Hall generators being operated with impressed control current and having Hall signal paths, N voltage to current converters each having an output and each being coupled to the Hall signal path of a different one of the Hall generators, and a common output connected to each of the outputs of the voltage to current converters.

Abstract: An isolation amplifier circuit is described that utilizes a magnetic field in combination with a Hall effect device to isolate input signals and output signals. The input signal is applied to a conducting coil that produces a magnetic field in a Hall effect material through which current is flowing. Because of the Hall effect, terminals on the sides of the Hall effect material can provide a voltage difference. This voltage difference is amplified and applied to a second conducting coil. The second conducting coil is adapted to provide a magnetic field in the opposite direction from the magnetic field produced by the input signal. When the magnetic fields are identical, no difference in current flowing through the two terminals will be present. The output signal of the difference amplifier circuit will be a function of the input signal. According to a second embodiment, apparatus is included for cancelling ambient magnetic fields.

Abstract: A Hall element device comprising a plurality of Hall elements including a first and last Hall element, each of the elements including a first input, a second input, a first output and a second output; a control current circuit, electrically connected to each of the first input, for driving each of the Hall element; and a circuit, electrically connected between adjacent Hall elements, for maintaining the second output of the one adjacent Hall element and the first output of the other adjacent Hall element at the same potential and for preventing current from passing across the adjacent Hall elements, the circuit including a first input electrically connected to the second output of the one adjacent Hall element, a second input electrically connected to the first input of the other adjacent Hall element, and an output electrically connected to the second input of the other adjacent Hall element, whereby the voltage across the first output of the first Hall element and the second output of the last Hall element

Abstract: Thermoforming equipment includes a solid state sensor adapted to determine when a sheet of thermoplastic material has been clamped between a forming mold and a heating platen. Clamping force is provided by a cutter blade carried by said mold around the periphery thereof. Electronic control circuitry responsive to the sensor maintains the thermoplastic sheet in clamped relation without being severed by the blade. After the thermoplastic sheet has been formed into an article defined by the mold, the mold and platen are permitted to continue to close beyond the point sensed by the sensor, permitting the blade to penetrate the sheet and sever the formed article therefrom.

Abstract: A Hall-effect element is connected at one Hall current terminal to ground and at the other Hall current terminal to a DC voltage application circuit. Two Hall voltage terminals of the Hall-effect element are coupled with the base and the emitter of a first transistor, respectively. A second transistor is connected in series to the first transistor in such a way that the collector of the second transistor is fed back in current mode to the emitter of the first transistor.

Abstract: An integrated circuit in which the Hall-Effect device and the sensing circuit can be incorporated on a single monolithic chip includes a Hall-Effect generator responsive to a magnetic flux change for generating a Hall-Effect voltage. A differential amplifier and current mirror circuit are coupled to the Hall-Effect device in order to vary or track the threshold voltage of the differential amplifier circuit in accordance with the output voltage from the Hall-Effect device irrespective of current changes in the Hall-Effect device due to temperature variations.

Abstract: A magnetic field is determined with a Hall element having a high sensitivity. Such an element is very susceptible to a variation of environmental temperature and thus requires a compensation thereof for the determination of a magnetic field. Two electric signals, indicative of the magnitudes of the Hall voltage and the temperature, respectively, are produced and fed into respective inputs of an analog calculator to thereby indicate the determined magnitude of the magnetic field automatically. In one aspect of the invention, the temperature signal may be obtained by detecting a control voltage across the control current terminals of the Hall element during passage of the control current therethrough. Alternatively, it may be obtained by means of a thermistor.

Abstract: An isolator circuit of the type designed to accept an input current and to generate a corresponding output current which is isolated from the input. The isolator circuit is formed with a core developing a flux in response to the input current and having a feedback winding for carrying the isolated output current. A magneto-sensitive element, such as a Hall effect element, responds to flux in the core, and an amplifier receives the output of the magneto-sensitive element and supplies a current to the feedback winding so as to cancel the flux produced in the core due to the input current. Improved frequency response is attained by means of a compensation winding disposed to respond to the difference between the flux produced by the input current and the flux produced by the output current.