Abstract: Circuit for driving a load, comprising: two input terminals for connection to a source of a supply voltage; a first and a second output terminal for connection to the load; at least one inductor coupled between one of the output terminals and a corresponding connection node; at least one arrangement comprising a switch coupled between one of said input terminals and one of said connection nodes, a diode being connected between said one connection node and the other input terminal; a control unit for controlling said one or more switches; wherein each arrangement and corresponding diode are designed to allow the voltage over the opened switch of said arrangement to return to substantially zero before said switch is closed, the control unit being designed to provide a signal for closing the switch when a substantially zero voltage over said opened switch is detected. Turning the switch on at a substantially zero voltage means that switching losses are greatly reduced, and this without complicating the circuit.

Abstract: In a bride circuit comprising a lamp choke that might partially saturate during the ignition of the lamp, at least one of the switches is switched off when the amount of charge displaced through it in forward direction equals a predetermined value. Despite the partial paturation of the lamp choke the amplitude of the ignition voltage is thereby effectively controlled.

Abstract: The lighting device comprises at least one emitter (10) of white light (9) produced by an initial radiation (1) and a secondary radiation (2), an electronic control circuit (11) to control the lighting, and a communication circuit (12). The electronic circuit (11) controls power supply of the light emitter to emit a modulating light signal (3, 4, 31, 36) of said initial radiation according to a communication signal (13). Said modulating light signal is designed to be received by a light signal receiver (18) sensitive to the initial radiation (1). A lighting installation comprises a power supply line, at least one lighting device (8) and at least one electrical apparatus (95, 96) connected to a receiver (18) comprising a sensor (19) sensitive to the initial radiation (1).

Abstract: The power supply (20) for LEDs provides power to a LED light source (10) having a variable number of LEDs wired in series and/or in parallel. The power supply (20) uses current and voltage feedback to adjust power to the LEDs and provides protection to the LED light source (10). A feedback controller (27) compares sensed current and sensed voltage to a reference signal and generates a feedback signal, which is processed by a power factor corrector (124) to adjust the current flow through the transformer supplying current to the LEDs. A LED control switch (24) clamps a peak of the current to the LEDs to provide further protection to the LED light source (10). A short/open detection circuit (30) indicates any detection of a “LED outage” of the LED light source (10).

Abstract: A floating driving device for illumination includes a illumination unit having a first terminal and a second terminal. A first driver is electrically coupled to the first terminal of the illumination unit, for applying AC voltages to the first terminal. A second driver is electrically coupled to the second terminal of the illumination unit, for applying AC voltages to the second terminal in such a manner that the AC voltages at the first terminal and the second terminal are out of phase.

Abstract: An improved image projection lighting device is disclosed. Commands received by a communications port of the base housing may be acted upon to change zoom and focus values of a zoom and focus lens. A cooling system may be provided which compares an input air temperature of the image projection lighting device to an exiting air temperature to determine if a filter needs service. A video projector may project a first image comprised of first, second, and third separate images and the first separate image can be faded up to project light that is void of an image by a first command received at the communications port.

Abstract: A frequency synchronization device for a large LCD having a plurality of lamps as a background light source is disclosed. The device comprises a power amplification unit wherein one power amplification unit is electrically coupled to another amplification unit, each power amplification unit being electrically coupled to one or more of the lamps, adapted to generate a driving signal, and adapted to send the driving signal to the coupled lamp(s) for causing the lamps to operate at the same frequency; a plurality of current sampling elements each electrically coupled to one or more of the lamps for sampling current thereof; and control means comprising a control element and a diode, the control means being electrically coupled to current sampling elements so as to stabilize the current of the lamps. The connection and circuitry of the device are much simplified and improved.

Abstract: A power supply controller apparatus is provided for use in a power supply apparatus including a battery assembly. The power supply controller apparatus includes a controller that controls supplying power to a load from said battery assembly through a capacitor connected between first and second contactors by turning on and off each of contactors. The controller detects whether or not each contactor is welded based on an output signal from one output terminal of both ends of the capacitor, when the each contactor is controlled to be turned off and an AC signal is applied to one input terminal of (a) one end of the battery assembly, (b) the other end of the battery assembly, and (c) each connection point between secondary batteries of the battery assembly.

Abstract: A window covering system includes a window covering, a motor having a housing and a power supply inlet, for opening or closing the window coverings, and a modular motor converter. The modular motor converter includes a low voltage interface for functional attachment to the motor, a housing for the low voltage interface, a standard motor power supply connector incorporated into the housing and fitting into the motor power supply inlet, and at least one attachment arm, preferably two, that clips onto the motor housing and permits quick clip-on and removal from the motor. In one form, the modular motor converter further includes a remote radio frequency control for functional attachment to and control of the motor. The modular motor converter also includes means for pre-setting silent stop of the motor end positions. The housing permits external access to motor dip switches.

Abstract: A model train on-board microprocessor provides basic lighting and motor operation and control. A socket provides a seamless instant remote control upgrade using industry standard remote control devices. The device provides new and useful functions and features for more prototypical operation by augmenting the industry standard remote control device capabilities. These new functions and features are made accessible from the remote control device companion transmitter with unique keypad sequences.

Abstract: A motor driving device includes a motor having three-phase driving coils, a power feeder for powering the coils, and a power feeding controller for controlling a power feeding method. The controller controls electrical potentials of the coils in a period of applying a voltage to the coils to be a power-supply voltage potential or the grounding potential by turning on or off transistors in the power feeder during a first feeding period which starts from a motor halt status and ends when the motor is driven at a given speed. During a second feeding period where the motor is driven at a speed over the given speed, the controller controls the potential such that the coils are opened by turning off the transistors or the potential becomes the power-supply voltage potential. This structure allows the motor driving device to drive the motor at a lower noise with less vibrations.

Abstract: Featured is a controller for a motor that is ultra-compact, with a power density of at least about 20 watts per cubic cm (W/cm3). The controller utilizes a common ground for power circuitry, which energizes the windings of the motor, and the signal circuitry, which controls this energization responsive to signals from one or more sensors. Also, the ground is held at a stable potential without galvanic isolation. The circuits, their components and connectors are sized and located to minimize their inductance and heat is dissipated by conduction to the controller's exterior such as by a thermally conductive and electrically insulating material (e.g., potable epoxy). The controller uses a single current sensor for plural windings and preferably a single heat sensor within the controller. The body of the controller can also function as the sole plug connector.

Abstract: An improved variable speed fan controller for use in devices such as laser printers. The controller automatically adjusts its output signal to fans such that a fan quickly settles into an appropriate operating speed, even if the fan has been newly installed into the equipment. The controller can store values in non-volatile memory, if desired, to keep track of recent changes in the fan's operating parameters and corresponding control signal values. The controller is able to control relatively inexpensive fans that don't necessarily operate at a predictable fan rotating speed under repeatable conditions and control signals, by controlling the fan to an initial or predetermined rotating speed; if the fan isn't running within a suitable range of rotational speeds, then determining whether a fine or coarse adjustment should be made to the fan's rotational speed. The controller makes appropriate adjustments until the fan's rotational speed is within acceptable operating tolerances.

Abstract: A system and method for sensing capacitance at the edge of a movable barrier and for detecting an obstruction includes positioning a conductive member within or about a holder. A sensed capacitance between the conductive member and ground. A controller is coupled to the sensor. The controller determines whether an obstruction exists within a path of the barrier by analyzing the sensed capacitance. The conductive member and holder move away from a physical reference as the physical reference is approached such that the sensed capacitance between the conductive member and the physical reference remains below a predetermined threshold.

Abstract: When either a command value or an actually measured value is appropriately selected as an angular velocity used for the frictional torque calculation, the frictional compensation can be made valid at all times in both the case in which a robot is actively operated according to an angular velocity command and the case in which the robot is passively operated being pushed by an external force. In the case where a motor rotating direction and a collision direction are reverse to each other after a collision has been detected, the control mode is switched from the positional control to the electric current control and a torque, the direction of which is reverse to the direction of the motor rotation is generated by the motor, so that the motor rotating speed can be reduced and the collision energy can be alleviated.

Abstract: In an AC or DC motor operation and power generation system, a periodic transformation system reduces or prevents harmonic distortion, reduces resistance or impedance, and improves energy efficiency in a signal either consumed, such as in a motor, or produced, such as in a generator. In one embodiment, the TruScale Reactance Transformation System or the Eastern Modified TruScale Octave Transformation System are the periodic transform systems provided to prevent overtone collisions in current and voltage signals, in order to maximize energy spectral density, and to precondition either DC or AC signals.

Abstract: A technique for reconstructing phase currents based on measurements of a DC bus current. Non-observable regions of DC bus current samples to reconstruct phase currents are reduced in size by using two phase space vector modulation. The non-observable regions can be further reduced by omitting deadtime insertions for switch actuations when output current is higher than a given threshold. Voltage command vectors in non-observable areas can be formed by two additive vectors of differing phase and magnitude to obtain an observable DC bus current reflecting phase current. The additive vectors have the same combined time average value as that of the voltage command vector.

Abstract: The invention provides a motor for a brushless DC motor, which has small torque ripple even if a trapezoidal wave current is supplied and has a small size and reduced motor noise, and a drive control device for the motor as well as an electric power steering device using the motor and the drive control device. Respective phase current command values are calculated on the basis of vector control. Pseudo-vector control for controlling respective phases separately is used as current feedback control.

Abstract: Abstract of the Disclosure A system and method for controlling an electric motor is disclosed. The method comprises determining the operating load of the electric motor and then calculating the voltage to be applied to the electric motor in response to the operating load. The voltage to be applied operates the motor in an efficient manner for the given load. The frequency of the voltage to be applied to the electric motor is calculated in response to the operating load such that the frequency of the voltage to be applied operates the motor in an efficient manner. Power is applied to the motor with the voltage and frequency calculated in order to operate the motor in an efficient manner for the given load.

Abstract: A hybrid power/propulsion system for a vehicle is provided that combines a fuel cell with a battery. A fuel cell, which uses a hydrogen and oxygen supply in fluid communication with the fuel cell, is combined with a battery system for power generation for a vehicle. The fuel cell is used when a low power is required by the vehicle, and the fuel cell is used in combination with the battery system when high power is required by the vehicle. The vehicle can be a land or marine vehicle, which can be a surface vessel or underwater vehicle.

Abstract: An apparatus for jumping and charging a remote battery. The apparatus includes a charger, positive and negative charge connectors operable to be connected to the remote battery, an auxiliary battery having positive and negative terminals, and positive and negative jumper connectors separate from the positive and negative charge connectors. The positive and negative jumper connectors are connected to the positive and negative terminals of the auxiliary battery and are operable to be connected to the remote battery. The apparatus further includes a selector responsive to connecting the positive and negative charge connectors to the remote battery and operable to connect the charger to the auxiliary battery when the charge connectors are not connected to the remote battery and to connect the charger to the positive and negative charge connectors to charge the remote battery when the positive and negative charge connectors are connected to the remote battery.

Abstract: A method is provided for inductively charging a rechargeable battery of a portable device in a vehicle via a primary circuit that includes a primary inductive coil, a secondary circuit that includes a secondary inductive coil, and a rectifying circuit electrically coupled to the rechargeable battery. A primary coil is energized with a supply voltage. A frequency of the supply voltage is varied. A peak voltage of the primary circuit is detected. The frequency of the supply voltage is adjusted to a respective frequency associated with the peak voltage.

Abstract: An electronic apparatus is provided. A component part containing chamber provided in the inside of a case constituting an armor of an electronic apparatus is so configured that a rectangular plate-like battery can be mounted and dismounted via a rectangular first opening opened in the lower surface of the case. One side wall in the vicinity of the first opening is provided with a second opening, and a component part containing space communicated with the second opening is provided in the inside of the case. A holder is provided which includes a first plate portion detachably attached to the second opening to shut off the second opening, and a second plate portion projecting from the first plate portion and extending in the component part containing space in the condition where the first plate portion shuts off the second opening, and a separable body is contained in the component containing space together with the holder.

Abstract: A combination including a battery pack and a battery charger operable to supply a charging current to the battery pack. The battery pack includes a first battery terminal, a second battery terminal, and a battery cell having a present state of charge. The battery cell is coupled to at least one of the first battery terminal and the second battery terminal. The battery pack also includes a battery microcontroller coupled to at least one of the first battery terminal and the second battery terminal. The microcontroller is operable to measure the present state of charge of the battery cell to produce battery cell present state of charge measurements. The battery charger includes a first charger terminal configured to couple to at least one of the first battery terminal and the second battery terminal and a second charger terminal configured to couple to at least one of the first battery terminal and the second battery terminal.

Abstract: Disclosed is a mobile communication terminal having a universal serial bus (USB) interface unit therein and particularly, a mobile communication terminal in which a USB interface unit is mounted to a battery. USB contacts are formed at a board of a body and a battery, respectively, a USB interface unit is provided at an upper portion of the battery, and then the battery is mounted upside down to the terminal, such that the USB interface unit is inserted into an outside device and accordingly the USB communications are performed. Therefore, the mobile communication terminal cannot only download the data but also be recharged through, for example, a computer.

Abstract: A battery pack with a housing and a plurality of cells disposed in the housing and electrically coupled to provide a storage capacity between about 2.17 and 2.67 ampere hours with an equivalent lithium content between about 6.5 and 8.0. The plurality of cells includes a first battery disposed in the housing and including a first plurality of cells connected in series and a second battery disposed in the housing and including a second plurality of cells connected in series, wherein the first battery and the second battery are operable in a storage mode and a use mode.

Abstract: A battery pack having no need to fill a gap between a bare cell and a protective circuit module includes a safety vent adapted to properly function even after molding has been completed and a PTC thermistor having characteristics which do not degrade during manufacturing processes. A bare cell, which has a protective circuit module and a PTC thermistor mounted thereon, is enclosed by an integral case. An exposed area of the case is covered with a resin. A lead is positioned on a safety vent formed on the bare cell to prevent the safety vent from being fractured by a resin of a high temperature and pressure during a resin filling process. The resin does not reach the protective circuit module and the PTC thermistor so that its heat is not transmitted to them.

Abstract: A charging unit for charging a battery of a power tool containing a base with a cavity defined by a side wall and a top wall, at least one protrusion extending from one of the side wall or the top wall, a cord, and a strain relief positioned around the cord and located within the cavity. The cord may be wrapped around the at least one protrusion, thereby providing flexibility in the direction of the cord and a means for eliminating excess cord between the charging unit and the electrical outlet when the unit is in operation. The base may also include a slot to receive and stabilize the cord. In addition, a method is provided for providing flexibility in the direction of the cord in a charging unit. The method includes providing an article having a cord, a cavity with a top wall, and at least one protrusion extending from one of the side wall or the top wall; and wrapping the cord around the at least one protrusion.

Abstract: An AC power source is coupled to a step-up transformer that provides a rectified DC output voltage to charge an intermediate capacitor. A high voltage electronic switch is turned ON and OFF by a control signal to couple and decouple the intermediate capacitor to the input of an inductor that supplies current to a capacitor bank. A switching regulator controller generates a control signal to vary the turn ON and OFF times of the electronic switch to generate a controlled current through the inductor while the voltage across the capacitor bank varies over a positive and negative voltage range during charging and discharging of the capacitor bank. The controlled current through the inductor is maintained while the capacitor bank is discharged. The value of the controlled current may be constant or varied in response to input and output voltage and current parameters.

Abstract: A power supply with a high voltage current regulated output wherein input devices are gated ON and OFF to regulate the output current. The output current is coupled through a current limiting inductor to a high voltage fast electronic switch (E-switch) that turns ON and OFF much faster than the power supply can shut down. The electronic switch is bypassed with a resistor network that is sized to dissipate slightly in excess of the full power rating of the power supply during a shut-down cycle. The electronic switch is normally gated ON providing a low impedance path for current charging the capacitor bank. When a short circuit condition is sensed, the E-switch is turned OFF and the resistor network limits the short circuit current, limits the voltage across the E-switch, and dissipates any energy stored in the inductor and the power supply circuitry during power supply shut-down.

Abstract: A collapsible battery charger is provided for charging batteries each having a pair of contact terminals on opposite ends. The battery charger includes a housing structure having a first upstanding wall and a sliding tray having a bottom wall and a second upstanding wall which is generally parallel to the first upstanding wall. The sliding tray is movable between a first position in which the first and second upstanding walls are adjacent to each other and a second position in which the first and second walls are spaced from one another. The tray is configured to hold one or more batteries for charging. The battery charger further includes at least one pair of contacts including a first contact provided on the first upstanding wall and a second contact provided on the second upstanding wall. The first and second contacts are adapted to contact the first and second contact terminals of a battery.

Abstract: The charger includes a controller, a battery power source having at least two power settings connected to the controller, a power supply connectable to an outside power source, the power supply receiving a current and voltage from the outside power source for providing power to at least one of the controller and the battery power source, and a foldback circuit for switching between two power settings depending upon at least one of the current and voltage received from the outside power source.

Abstract: A battery monitoring device of a battery pack configured for powering a cordless power tool may include an integrated circuit connected to a microprocessor of the pack that is external to the integrated circuit, and which is connected to each of N battery cells of the pack. The integrated circuit may be configured to take, singly or sequentially, a sampled reading comprising one of an individual cell voltage or a total pack voltage for all cells in the pack. The sampled reading is filtered in the integrated circuit prior to being read by the microprocessor.

Abstract: A signal generator provides an output signal having a series of pulses and a pulse repetition rate. The signal generator includes an energy storage circuit and a switch control circuit. The energy storage circuit includes a switch operated by the switch control circuit. After delivery of a pulse of the output signal, the switch control circuit operates the switch in a first mode to provide the pulse repetition rate of the output signal. The switch control circuit also operates the switch in each of the first mode and a second mode at a switching rate, wherein relatively more energy from a battery is stored as a consequence of the second mode than is stored as a consequence of the first mode. Energy from the battery is stored for delivery in a pulse of the output signal. The switching rate is compensated in accordance with a temperature of the battery and a voltage of the battery. Compensation maintains the battery voltage above a minimum value.

Abstract: An energy storage device for use with an electric vehicle includes an electrical energy storage device configured to be coupled to an electrical traction system of the electric vehicle to provide electrical power to the electrical traction system. The energy storage device also includes a sensor integrally mounted within the electrical energy storage device and configured to measure a voltage of the electrical energy storage device. The sensor also includes a status indicator integrally mounted to the electrical energy storage device and configured to provide a visual indication of the voltage.

Abstract: A method is described that induced dielectric breakdown within a capacitor's dielectric material while driving a current through the capacitor. The current is specific to data that is being written into the capacitor. The method also involves reading the data by interpreting behavior of the capacitor that is determined by the capacitor's resistance, where, the capacitor's resistance is a consequence of the inducing and the driving.

Abstract: In an AC adapter provided with a circuit board having first and second surfaces opposite to each other in a thickness direction, a transformer portion is mounted on the circuit board. A secondary capacitor is connected to an output side of the transformer portion. The secondary capacitor has a low profile and extending in parallel to the circuit board. Thus, the AC adapter as a whole is reduced in external size. Preferably, the transformer portion is mounted on the first surface while the secondary capacitor is mounted on the second surface.

Abstract: A central processing unit (CPU) is disclosed. The CPU includes a CPU die; and a power management die bonded to the CPU die in a three dimensional packaging layout.

Abstract: A method and apparatus for multi-phase transformers are described. In one embodiment, a coupled inductor topology for the multi-phase transformers comprising N primary inductors. In one embodiment, each primary inductor is coupled to one of N input nodes and a common output node. The transformer further includes N?1 secondary inductors coupled in series between one input node and the common output node. In one embodiment, the N?1 secondary inductors are arranged to couple energy from N?1 of the primary inductors to provide a common node voltage as an average of N input node voltages, wherein N is an integer greater than two. Other embodiments are described and claimed.

Abstract: A central processing unit (CPU) is disclosed. The CPU includes a CPU die; and a voltage regulator/converter die bonded to the CPU die in a three dimensional packaging layout.

Abstract: There are provided a control circuit of a DC-DC converter of a synchronous rectification system which can realize rapid lowering of an output voltage with low power consumption at the stop of power supply, and a control method thereof. While a power supply stop signal is at low level, a control part controls an NMOS transistor according to the output signals of a comparator and a flip-flop circuit. While the power supply stop signal is at high level, the control part masks a reverse current detection signal and the output signal of the flip-flop circuit to control the NMOS transistor according to a detection signal of a comparator. When a choke coil current is reversely flowed and an output voltage is lowered to an output reference voltage corresponding to a reference voltage, the NMOS transistor is brought to the non-conductive state to regenerate the electric power to an input terminal.

Abstract: A power measuring apparatus capable of accurate power measurement through segment averaging of a signal obtained by code division multiplexing a plurality of channels having different periods or timings at which their power levels change, a power control apparatus and radio communication apparatus provided with this power measuring apparatus and a power measuring method are disclosed. In this power measuring apparatus, an averaging start timing control section (105) inputs an averaging start timing signal to an averaging section (103) based on information input from a power change timing analysis section (106) when a longest segment identified by the power change timing analysis section (106) arrives. When the averaging start timing signal is input, the averaging section (103) starts to calculate a segment mean value of the input signal.

Abstract: Methods for testing a semiconductor circuit (10) including testing the circuit and modifying a well bias (14, 18) of the circuit during testing. The methods improve the resolution of voltage-based and IDDQ testing and diagnosis by modifying well bias during testing. In addition, the methods provide more efficient stresses during stress testing. The methods apply to ICs where the semiconductor well (wells and/or substrates) are wired separately from the chip VDD and GND, allowing for external control (40) of the well potentials during test. In general, the methods rely on using the well bias to change transistor threshold voltages.

Abstract: A start signal output circuit having an RF/DC conversion circuit to which radio frequency power (RF) of specified frequency is inputted and from which a direct current potential (DC) is outputted, comprises a detection/amplification circuit 210 which includes a voltage doubler wave-detector circuit 10 configured including a sensing diode Q1 (Tr34) for sensing the RF power, a differential amplifier including differential pair transistors Tr31 and Tr32, and a current mirror circuit. A base current of one Tr31 of the differential pair transistors is brought into substantial agreement with a DC component of a current flowing through the sensing diode Q1 (Tr34). A total of currents flowing through the differential pair transistors Tr31 and Tr32 is regulated to a substantially constant value by the current mirror circuit. Thus, the start signal output circuit which is small in size, high in sensitivity and low in power consumption can be realized.

Abstract: The present invention provides a current sensor capable of adjusting an offset value at a zero magnetic field more easily and detecting a current magnetic field generated by a current to be detected with high sensitivity and high precision. The current sensor has: first and second magnetoresistive elements disposed along a conductor so that resistance values change in directions opposite to each other in accordance with a current magnetic field generated by a current to be detected flowing in the conductor; and first and second constant current sources that supply constant currents equal to each other to the first and second magnetoresistive elements, respectively. The current sensor further includes a differential amplifier that detects the difference between voltage drops occurring in the first and second magnetoresistive elements by the constant current. The current to be detected is detected on the basis of the difference between the voltage drops.

Abstract: The present invention relates to an insert block for testing semiconductor devices. The insert block comprises one or more pushers, installed in a block body having a loading space to accommodate a semiconductor device under test, including a first push rod to apply force to one of adjacent sides of the semiconductor device under test and a second push rod to apply force to the other thereof. Accordingly, firm centering of semiconductor devices under test relative to the contact pins of the test socket along the two perpendicular axes (for instance, x and y axes) on the top or bottom surface of the semiconductor device is achieved and leads to the proper interfaces between the external terminals of the semiconductor device under test and the contact pins of the test socket, and thereby improves the quality of connection therebetween.

Abstract: An integrated circuit having a speed measurement circuit that generates an indicator of a speed of the integrated circuit in response to a test signal. The speed measurement circuit obviates the need to repeatedly apply test signals at different clock frequencies to an integrated circuit or to externally measure delay time.

Abstract: A method and a device for determining motion parameters of a conductive, profiled surface (22) relative to a sensor (3), with the sensor (3) comprising at least one coil for generating an electromagnetic alternating field, which is subjected, because of the feedback resulting from position changes between the surface (22) and the sensor (3), to a variation, which is determined by means of the coil (16). The position change is derived from the coupling impedance (Zc) of the coil (16), and the real component (Rc) and the imaginary component (Xc) of the complex coupling impedance (Zc) of the coil (16) are determined, with a distance d between the sensor (3) and the surface (22) being computed based on the determined values while using an algorithm as a basis.

Abstract: A method for determining the angular position of a rotating object and rotary encoder is disclosed. In one embodiment, the method includes a method for determining the angular position of an object rotating about a rotation axis in a rotation direction and having a coding pattern, using a sensor that senses the coding pattern, including ascertaining the coarse angular position of the rotating object with respect to the sensor whilst taking account of the coding pattern at a first instant. The exact angular position of the rotating object is ascertained with respect to the sensor whilst taking account of the coarsely ascertained angular position and also whilst taking account of at least one section of the coding pattern which extends counter to the rotation direction proceeding from that location of the coding pattern which is assigned to the coarse angular position. An output signal is provided containing items of information about the exact angular position of the rotating object with respect to the sensor.

Abstract: A voltage generating section applies first and second voltages having inverted polarities to a sensor section. The sensor section outputs a voltage value corresponding to a change in geomagnetism. A bias magnetic field generating section applies an alternating current bias magnetic field to the sensor section. A detecting section detects voltages with respect to the first and second voltages when the alternating current bias magnetic field is applied in positive and negative directions. By taking the difference between the detected voltages, an offset voltage to be outputted from a magnetism detecting circuit is eliminated.