Abstract: A circuit for generating a high voltage alternating current to drive a load has a current source having a first terminal and a second terminal. The circuit further has an output terminal and a circuit ground terminal. A first switch will conduct between the first terminal of the current source and the circuit ground terminal when the first switch is closed. A second switch will conduct between the first terminal of the current source and the output terminal when the second switch is closed. A third switch will conduct between the second terminal of the current source and the circuit ground terminal when the third switch is closed. A fourth switch will conduct between the second terminal of the current source and the output terminal when the fourth switch is closed. A load is coupled to the output terminal and the circuit ground terminal.

Abstract: The invention relates to a method and a device for operation of ah high pressure discharge lamp with a low-frequency current of alternating polarity, whereby the high pressure discharge lamp is operated during a start phase at a higher power than the rated power thereof. According to the invention, the high pressure discharge lamp is provided with a current, at least during the start phase, with a commutation time of less than or equal to 40 microseconds.

Abstract: A device has an electrical connector, a radiation generator, and a flexible carrier with circuitry that is operatively coupled between the connector and the radiation generator. In response to electrical power received through the connector, the circuitry energizes the radiation generator, and the radiation generator emits radiation. In a different embodiment, a device has an electrical connector, a radiation generator, and a member with circuitry embedded therein. The circuitry is operatively coupled between the connector and the radiation generator. In response to electrical power received through the connector, the circuitry energizes the radiation generator, and the radiation generator emits radiation.

Abstract: The present invention provides a light emitting diode lamp, which includes at least a light emitting diode and a control circuit. The light emitting diode lamp has an anode pin, a cathode pin, and a synchronous pin. The anode pin and the cathode pin receive a DC voltage, and the synchronous pin is connected to the control circuit. Moreover, the present invention provides a synchronous light emitting diode lamp string, which includes a plurality of light emitting diode lamps and at least a power adapter. Each light emitting diode lamp has a synchronous pin, and all synchronous pins are connected together. The control circuit can control the color changing of the light emitting diode based on a reference signal from the synchronous pin.

Abstract: A display panel driving circuit includes an input part for amplifying an input on-off signal so as to generate a first on-off voltage signal, a voltage signal generation part for generating a second on-off voltage signal which is varied in response to variations of the first on-off voltage signal, and an output part generating a push-pull output voltage as a driving voltage so as to drive a display panel in response to the first and second on-off voltages. The display panel driving circuit further includes a controlling part for controlling the voltage signal generation part so that a difference between on and off voltages of the second on-off voltage signal is not smaller than a predetermined voltage. Therefore, the push-pull output voltage whose response speed is well balanced when the push-pull output voltage increases and decreases can be generated without increasing electric power consumption and a circuit area.

Abstract: A control circuit may include a first feedback input terminal which receives the cathode terminal voltage of light-emitting elements from a current driving circuit as a feedback signal. Such an arrangement controls the ON/OFF state of a switching element such that the cathode terminal voltage approaches a predetermined voltage. A second feedback input terminal may be included to receive the anode terminal voltage of the light-emitting elements as a feedback signal. Such an arrangement controls the ON/OFF state of the switching element such that the anode terminal voltage does not exceed a predetermined threshold voltage. A feedback output terminal may be included of the current driving circuit which allows the cathode terminal voltage of the light-emitting elements to be input to a control circuit for the switching regulator as a feedback signal. The control circuit and the current driving circuit may be integrally provided in the form of separate semiconductor chips.

Abstract: A drive device for a light emitting diode element may include a light emitting diode element circuit part configured to be formed by connecting at least one light emitting diode element based on a predetermined connection form, a power supply unit configured to generate a direct-current (DC) supply voltage for driving the light emitting diode element of the light emitting diode element circuit part for light emission of the light emitting diode element, and apply the DC supply voltage to the light emitting diode element circuit part, a power-supply application on/off unit configured to be provided to turn on/off application of the DC supply voltage to the light emitting diode element circuit part, and a current control circuit part configured to be caused to switch its operation so as to carry out constant current operation if application of the DC supply voltage is in an on-state and carry out voltage keeping operation if application of the DC supply voltage is in an off-state.

Abstract: An inverter controller dives an inverter to operate at a switching frequency selectively from one of a preheating frequency (f1), a starting frequency (f2), and a lighting frequency (f3) which are different from each other, thereby giving a preheating mode, a starting mode, and a lighting mode. A reset means is provided to make the starting mode upon lowering of a voltage supplied to the inverter below a first threshold, while an inverter stop means is provided to stop the inverter upon detection of abnormality of a discharge lamp. A timer generates a signal determining the start of the preheating, starting, and/or lighting modes, and generates a reset signal disable signal for disabling the reset means, an inverter stop disable signal for disabling the inverter stop means. The inverter controller includes a frequency sweep means for varying the switching frequency gradually from the starting frequency to the lighting frequency.

Abstract: Electronic control system for an actuation device of operating groups of a vehicle comprising an electronic gearcase that allows the activation and deactivation of said at least one device to be managed. The gearcase defines a first operating condition of the selective actuations defined as rest, a second condition defined as block and a third condition defined as transitional, which is a passage step between the other two conditions.

Abstract: Disclosed is a method for controlling a voltage of a DC link for an electric vehicle, which can reduce a capacitance of the DC link interposed between an inverter and a DC/DC converter. The method for controlling the voltage of the DC link in a power system of a vehicle including a battery, a DC/DC converter, the DC link, an inverter, a motor, and a control part controlling the DC/DC converter and the inverter includes the steps of installing a compensator in a control loop of the control part such that a DC link current of the DC/DC converter follows a DC link current of the inverter, calculating a predetermined compensation term based on information of the motor inputted into the compensator, and applying the compensation term to a voltage node in the control loop of the control part in the compensator.

Abstract: An on-off duty ratio of a transistor that increases and decreases a current applied to a field coil of an alternator is monitored. When the duty ratio is 100%, the electric generation capability of the alternator is at a maximum, and the battery current of a battery exceeds a predetermined current limit. Under these conditions, a torque limit is set to tighten a limit on the torque output from a motor. The motor is thus controlled within a range determined by the set torque limit. As a result, the motor can be controlled while the electric power outputs and requirements of the alternator, the battery and the motor are balanced, without having to directly detect the high voltage electric power of the alternator. Accordingly, the flow of excessive current in the battery can be impeded, and deterioration of the battery can be avoided.

Abstract: A hybrid vehicle includes: first and second rotary electric machines; a matrix converter connecting the first and second rotary electric machines to each other to provide AC to AC power conversion between both the rotary electric machines; a battery connected to an electrical path branched off between the matrix converter and the second rotary electric motor; an inverter interposed among the battery, the matrix converter and the second rotary electric machine to convert AC power to DC power and vice versa; and a controller. The controller activates the first rotary electric machine with power fed from the battery and restrains the change in torque output of the second rotary electric machine at the activation of the first rotary electric machine.

Abstract: A monitoring device for an electric motor has in input a signal representing zero crossings of the back-electromotive force of the motor and comprises a monitor that detects the signal in first periods of time arranged around instants of time in which the zero crossings are expected. The device comprises a setting circuit that sets second periods of time that are less than the first periods of time and each second period of time is centered on the instant of time in which the zero crossing is expected. The monitor comprises a detector that tests whether each actual zero crossing occurs inside the second period of time and a controller that modifies by a quantity the subsequent period of electric revolution time between two consecutive expected instants of zero crossing if said actual zero crossing occurs outside the second period of time.

Abstract: In a speed control device including a speed instruction generating unit, an addition computing unit, a speed control unit, a current controlling unit, an inertia estimating unit, an inertia setting unit, a switching unit and a constant setting unit, when it is possible to perform accelerating or decelerating operation of the electric motor to estimate the inertia moments of the electric motor and a driving target thereof, an operation is carried out to derive an inertia moment estimation value. The proportional gain of the speed control unit is set through the switching unit and the constant setting unit on the basis of the inertia moment estimation value. When it is impossible to perform the above operation, the proportional gain of the speed control unit is set through the switching unit and the constant setting unit on the basis of the inertia moment manual set value.

Abstract: A method of preventing concurrent or quasi-concurrent commutations of a pair of phase shift modulation (PSM) drive signals of an output bridge stage driving an electrical load includes establishing a threshold level of a programmed current level to be transmitted though the electrical load. The method also includes, if the programmed current level is lower than the threshold level, enhancing a time offset between commutation edges of the pair of PSM drive signals by a minimum time.

Abstract: The invention concerns a reversible current rectifier, for connection to part of a polyphase network and to a continuous bus comprising a plurality of rectifier cells each rectifier cell including a rectifying device and a on-way electronic switch connected in anti-parallel with the rectifier device, the rectifying devices of different cells being arranged so as to form one rectifier. Each rectifier cell comprises means for controlling the electronic switch of the cell arranged to control the latter in closure after detecting a conduction of the rectifying device of the cell so as to enable current to be returned to the network. The control means are arranged to receive a signal external to the cell, for controlling the opening of the electronic switch, derived from another rectifier cell.

Abstract: The present invention provides a torque loop control method for servomotors utilizing discontinuous pulse width modulation that incorporates measuring the power factor in real time. Also included is a sine wave generator for software-based spectrum analysis.

Abstract: Methods and devices are provided for rotating an end effector on a long, flexible medical device. The methods and devices utilize an actuator mechanism that is effective to rotate an end effector on the distal end of an elongate flexible shaft. The actuator mechanism is movable between a freely rotatable position and a rotationally resistant position. When the actuator mechanism is in a freely rotatable position, the actuator mechanism can be rotated to impart torque to the end effector, and thus at least a distal portion of the elongate shaft, to cause the end effector to rotate. In order to prevent the actuator mechanism from “freewheeling,” wherein the actuator mechanism freely rotates in an opposite direction upon release rather than the end effector rotating in the desired direction, the actuator mechanism can be moved to the rotationally resistant position.

Abstract: A method and apparatus for controlling a haptic device. In one embodiment, the haptic device includes an actuator; an actuator sensor, producing an actuator signal indicative of the actuator velocity; a load; a load output sensor producing a load output signal indicative of the load position; and a controller in electrical communication with the load output sensor, actuator sensor and actuator. The controller controls the actuator in response to the actuator signal and the load output signal to provide a haptic response to a user. In one embodiment, the method for controlling an actuator of a haptic device includes the steps of producing an actuator signal indicative of the velocity of an actuator; producing a position signal indicative of the position of a load; and controlling the actuator in response to the actuator signal and the load output position signal to produce a haptic response to a user.

Abstract: A method and a controller for controlling a magnetic bearing device, in which a rotor is suspended for rotation around a shaft, are disclosed. Sensor signals are transformed to yield tilt displacement signals (S?x, S?y) which correspond to tilting displacements of the shaft in predetermined directions (x, y). From the tilt displacement signals (S?x, S?y), tilt control signals A?x, A?y) are derived; these are transformed to yield actuator control signals for driving electromagnetic actuators in the magnetic bearing device. According to the invention, tilting displacements for which the tilt vector rotates about the device axis (z) with a first predetermined sense of rotation are controlled separately from tilting displacements for which the tilt direction vector rotates about the device axis (z) with a second sense of rotation opposite to the first predetermined sense of rotation. In this way, control of nutation and precession can be achieved without influence from blade vibrations or shaft bending modes.

Abstract: The present invention relates to an apparatus and method for generating digital electrical signals which are representative of the angular position and rotational velocity of a rotatable shaft or similar movable mechanical component in a servomechanism. In particular, the present invention utilizes oversampling techniques to create an accurate, flexible and responsive method for determining shaft position on a high speed motor. The present invention also includes methods for overcoming deadtime losses and velocity lag.

Abstract: This invention first presents winding methods to make multiple printed coils on a thin multi-layered PCB. Multiple thin magnets can be laterally installed on a thin magnet board, too. Then, this invention presents variant but similar conceptual models of thin linear, rotary, and step motors and electromagnetic driver using such thin coil PCBs and magnet boards or just coil PCBs as the stators and the actuator. All models share similar innovation. Each printed coil or magnet of the actuator has the same polarity with the printed coils or magnets of the stators at its leading edge and/or has the opposite polarity with the printed coils or magnets of the stators at its tailing edge in the moving direction. So that each printed coil or magnet of the actuator is pulled by the printed coils or magnets of the stators at its leading edge and/or pushed by the printed coils or magnets of the stators at its tailing edge.

Abstract: A method and device for detecting an initial excitation phase of a stepping motor is provided, by which an initial excitation phase of a rotor corresponding to a position of a stopper can be detected with a unit of a stepping angle of a microstep drive which is smaller than that of a full step drive without using elements such as magnetoelectric elements. Upon appropriately changing an excitation phase of a stepping motor, on the basis of a generated pattern of an induced electromotive force in an exciting coil in a non-excitation state upon a full step drive, whether or not a pointer comes in contact with a stopper to stop a reverse rotation of the pointer and rotor is judged so that it is specified on which excitation phase the pointer and rotor are reversed, thereby detecting an initial excitation phase of the rotor corresponding to a position of the stopper.

Abstract: The position sensorless control apparatus is for controlling a synchronous motor having a permanent magnet rotor structure by generating fundamental voltage vectors used to designate on/off states of switching devices included in an inverter circuit thereof. The position sensorless control apparatus includes a current change rate detecting section detecting, as a current change rate, a change rate of a phase current flowing through the synchronous motor when a predetermined one of the fundamental voltage vectors is being generated, and a rotor magnetic pole position estimating section estimating, as a rotor magnetic pole position, a rotational position of a rotor of the synchronous motor on the basis of the current change rate detected by the current change rate detecting section.

Abstract: A synchronous motor controller is provided which is designed to diagnose whether a failure is occurring or not in energizing one of phase windings of a synchronous motor which is required to be energized first to start the synchronous motor. When such a failure is found, the controller reverses the synchronous motor slightly to bring one of the phase windings which is possible to energize properly to a starting position where the energization of the phase windings is to be initiated to start the synchronous motor in a required direction, thereby ensuring the stability in starting the synchronous motor even if any of the phase windings is failing to be energized.

Abstract: A capacitor, inductor, and power line are arranged in a series parallel combination tank circuit that operates over four quarters of a complete cycle. During the first quarter cycle: power is applied to the tank circuit, current flows through the inductor to the capacitor, current is stored in the inductor, and the capacitor is charged. During the second quarter cycle; current is released from the inductor as the capacitor discharges current to another parallel inductor or resistive load. During a third quarter cycle: current flows in the capacitor from the opposite direction, the capacitor is charged, current pushes out from the capacitor to the incoming power line, and current is stored in the inductor. During the fourth quarter cycle: the capacitor discharges in the opposite direction, current parallel to another inductor or resistive load flows in the opposite direction, and the inductor releases current to incoming power line.

Abstract: The invention relates to a filtering device connected between a rectifier module of a variable speed drive and an alternating current power supply network, the filtering device comprising an EMC filter comprising a common-mode inductor having a winding on each phase of the power supply network, the windings being magnetically coupled together. The filtering device comprises a shunt circuit connected in parallel with at least one of the windings of the common-mode inductor, the shunt circuit comprising passive components and making it possible to shunt a common-mode current flowing in the common-mode inductor in a frequency zone about a resonance frequency of the EMC filter.

Abstract: This invention provides a control method for a motor that calculates a voltage command value based on a difference between a current command value and a current detected value and controls a PWM based on the voltage command value. The control method includes steps of: detecting a failure or an undetectable state of a current detecting system; obtaining a current estimated value of a failure phase or an undetectable state phase by using the current detected value except the failure phase or the undetectable state phase when the failure or the undetectable state is detected; and continuously controlling the motor by using the current estimated value.

Abstract: The invention relates to an electric charger (1) comprising: an electrical energy storage module (3) having a connection interface (31) to an external battery (41, 42); an electrical generator (2) the energy supply for which can be controlled, in order to supply electrical energy to the storage module (3), at an operating point; and generator (2) control means (5) which are designed to adapt the operating point of the generator (2) when it is supplying electrical energy to the storage module (3) in accordance with information (530) relating to the state of the storage module (3) and information (520) relating to the state of the generator.

Abstract: A battery charging circuit is used by being connected to a direct-current power source. The battery charging circuit includes a control transistor, a backflow prevention transistor and a charging controller. The control transistor is disposed in a charging path between the direct-current power source and a battery, and is configured to control a direct-current voltage from the direct-current power source, and to output controlled direct-current voltage as a charging voltage. The backflow prevention transistor is disposed in the charging path, and is configured to output the charging voltage to the battery, and to be turned off when an electric current flows backward from the battery to the direct-current power source. The charging controller is configured to turn on the backflow prevention transistor when charging of the battery starts, and to turn on the control transistor after a fixed period of time elapses from a start of the charging.

Abstract: A straddle-type vehicle reliably cools a voltage regulator while inhibiting the voltage regulator from being negatively affected by water spray thrown up by a front wheel of the vehicle when it is running forward, or by flying objects that hit the vehicle from the front. The voltage regulator is attached to a front end side region of a rear arm.

Abstract: A method and apparatus is disclosed for starting and stopping a generator set that supplies power to a refrigeration system. An ambient temperature sensor is used rather than an in-box sensor in addition to a programmed microprocessor to regulate the operation of the generator. Unnecessary use of the generator is, thereby, limited which contributes to cost, energy and equipment savings and a cleaner environment while ensuring the required in-box temperature is maintained and the quality of perishable goods are not compromised.

Abstract: A bidirectional boost circuit for power factor correction includes a power factor control circuit and a pair of diodes, a pair of inductors, and a pair of switches. A first diode, a second diode, a first inductor, a second inductor, a first switch, and a second switch convert the AC input voltage, rectify the AC input voltage, and output an intermediate DC voltage. The power factor control circuit receives the AC input voltage and receives the intermediate DC voltage. The power factor control circuit regulates the DC output voltage. Based on the AC input voltage and the intermediate DC output voltage, the power factor control circuit controls an inductor current waveform by driving the first switch and the second switch to create a substantially sinusoidal current as seen by the power source that is in phase with the AC input voltage.

Abstract: A method of operating a converter circuit is disclosed, wherein the converter circuit has a converter unit with a multiplicity of controllable power semiconductor switches and the converter unit is connected at the AC voltage end to an electrical AC voltage network. According to the method, the controllable power semiconductor switches are controlled by means of a control signal.

Abstract: An output regulator comprises M switch arrays, where M is an integer greater than 2. A controller selectively enables N of the M switch arrays in response to a sense signal. The sense signal is based on an output of the output regulator. The controller generates drive signals to control the N of the M switch arrays, where N is an integer greater than or equal to 0 and less than or equal to M. When N is greater than 0, the controller dynamically sets a phase interval between the N of the M switch arrays to one of greater than 360/N or less than 360/N.

Abstract: A voltage converter having four switches Q1, Q2, Q3, Q4, connected in series and operated in pairs in a complementary fashion. An input voltage is provided across the four switches. A middle capacitor is connected in parallel with two middle switches Q2, Q3. Voltage output is provided across switches Q3 and Q4 (i.e. at a midpoint of the four switches). Series-connected output capacitors can be connected in parallel with the set of four switches. The middle capacitor alone or in combination with parallel connected capacitors, when connected to the input voltage or output terminals functions as a capacitive voltage divider for voltage conversion and/or regulation with extremely high efficiency and which can provide either step-down or step-up function. Also, an output inductor can be provided as a perfecting feature to further increase efficiency. Alternatively, two of the four switches can be replaced with rectifying diodes.

Abstract: In one embodiment, a feedback network of a voltage regulator is configured to adjust a value of a voltage divider responsively to a control word.

Abstract: Low ripple line-state dependent PWM DCDC converter controllers and methods for subscriber line interface circuit switching load regulation. In accordance with the method, line state is monitored to determine the target voltage for that state, and a DCDC converter is controlled responsive to the line state and the difference between the actual line voltage and the target voltage for that line state. The differences between the actual line voltage and the target voltage for that line state are split into different ranges, each range having a skip step size and a step size associated therewith, the step size determining how many equal pulse width pulses will be provided to the converter before the pulse width is adjusted by the step size and the process repeated. Apparatus for practicing the invention and variations thereof are disclosed.

Abstract: A switching power-supply circuit generates a predetermined output voltage by controlling a first switching transistor connected to a power supply and a second switching transistor connected between the first switching transistor and the ground. The switching power supply circuit includes a first driver, a second driver, a soft-start voltage generator and an error amplifier. The first driver drives the first switching transistor. The second driver drives the second switching transistor. The soft-start voltage generator generates a soft-start voltage that increases gradually after the time of start. The error amplifier amplifies an error voltage between a feedback voltage based on the predetermined output voltage and the soft-start voltage, and controls the first and second drivers in accordance with an amplified error voltage.

Abstract: A multi-phase DC-DC converter incorporates auxiliary resistor networks to feed back to the converter's supervisory controller voltages representative of secondary sensed currents associated with primary currents sensed relative to the common nodes of the respective phases, and derived from the output nodes for each phase. The auxiliary resistor network-coupling of these secondary sensed currents enables the controller to more completely take into account the influence of the currents of each channel on every other channel, whereby phase-balanced control of all converter channels is achieved, irrespective of symmetry of the integrated circuit layout of the different phases of the converter.

Abstract: A power supply circuit includes a standard voltage generator, a regulator, a capacitor and a discharging circuit. The standard voltage generator is configured to generate a standard voltage. The regulator is configured to control an output voltage by use of a reference voltage based on the standard voltage outputted from the standard voltage generator, and to be capable of being switched ON/OFF. The capacitor is connected in parallel to the regulator between the standard voltage generator and the regulator. The discharging circuit is configured to discharge electrical charges from the capacitor while the regulator is in an OFF state.

Abstract: A switching regulator. A pulse width modulation (PWM) unit comprises an output stage and generates a PWM driving signal to control the output stage, such that an inductor delivers an inductor current signal to the load, and a slope compensation unit outputs a slope compensation signal with a compensation slope proportional to a falling slope of the inductor current signal to the PWM unit according to the inductor current signal.

Abstract: An AC voltage regulator able to provide a desired voltage to any type of a given load within a predetermined range without any output power interruptions during any transition time, without distortion of the AC sine wave and without high current circulating through the circuit components during the voltage switching. The voltage regulator uses a single regulator transformer having a primary winding and a secondary winding. The secondary winding of the regulator transformer is connected in series between a power source and the load, while the primary winding of the regulator transformer is connected with the power source so that the primary and secondary windings have opposite polarities. The position of a plurality of switches can be variably set by the control circuit to control current flow through the primary winding and to provide a normal mode, a step-down mode, or a step-up mode.

Abstract: A local area networking apparatus comprises a power stage for connecting to a network cable for carrying carry power and data. The power stage comprises a main current flow path which includes a switch comprising at least one transistor positioned in the main current flow path and a current monitoring apparatus for monitoring current flow in the main current flow path, and wherein the current monitoring apparatus comprises a sensor which is not placed in series with the main current flow path. The current monitoring apparatus can comprise a current mirroring stage which is arranged to mirror current flowing in the main current flow path to a monitoring current flow path. The switch can be implemented as a set of switches.

Abstract: Bandgap reference circuits capable operating in low voltage environments. In the bandgap reference circuit, an operational amplifier comprises an output terminal and first and second input terminals, first and second transistors are coupled to the operational amplifier, and a first resistor is coupled between the output terminal of operational amplifier and the first transistor. A first resistor ladder is coupled between the output terminal of the operational amplifier and the second transistor and comprises a plurality of second resistors connected in series and a plurality of switches each having a first terminal coupled to a high-impendence path.

Abstract: The present invention provides an inductively powered sensor system having a primary conductive path capable of being energized to provide an electromagnetic field in a defined space. An inductive power pick-up is associated with a sensor and is capable of receiving power from the field to supply the sensor. The system includes a first sensing unit to sense the power available to the pick-up and a control unit to increase or decrease the power available to the sensor dependant on the sensed power available. A method of inductively powering a sensor, an inductively powered sensor and an animal enclosure including one or more primary conductive path of an inductive power supply are also disclosed.

Abstract: A method is disclosed that includes receiving a classification voltage at a powered device from a network. The classification voltage includes a baseline voltage level that is below an operating voltage range of the powered device and includes a sequence of distinct signal elements derived from the classification voltage. The method further includes detecting a number of signal elements of the sequence of distinct signal elements. A current is drawn until the number of signal elements exceeds a predetermined number.

Abstract: A test signal to be supplied to a driver section when the driver section is subjected to an operation test is generated by a test circuit. In the test circuit, the test signal can be generated by a burn-in control circuit in accordance with a clock signal TESTCK supplied from an outside source.

Abstract: It is an object of the present invention to provide a phase difference measurement circuit that can accurately measure any phase difference without requiring a pulse signal having a pulse width that is sufficiently narrower than a pulse width to be measured, i.e., a very-high-speed pulse signal, which is required when measuring a phase difference of two signals with accuracy. The phase difference measurement circuit is provided with a waveform control circuit (103) which outputs one (102) of two input signals for each predetermined period, a comparison pulse generation circuit (104) which converts a phase difference between the input signal (101) and the input signal (102) that is outputted for each predetermined period into a phase difference pulse (1042) at each predetermined timing, a periodic signal generation circuit (105) which generates a periodic signal (1051) by accumulating the phase difference pulse (1042), and a measurement circuit (106) which measures the period of the periodic signal (1051).

Abstract: A power detection system implemented using a pair of directional couplers and a transmission line (or equivalent) disposed between the directional couplers, wherein the transmission line (or equivalent) provides a 90° phase shift between the directional couplers. Accurate power detection is provided by combining the powers detected at each of the directional couplers, whereby the combined power is independent of load phase. The total power in the forward case is given by Pc1=2*Pf*C, where Pf is the forward power and C is the coupling coefficient the directional couplers. The total power in the reflected case is given by Pc1=2*Pf*C*(?2+D2), where Pf is the forward power, C is the coupling coefficient of said directional couplers, ? is the reflection coefficient, and D is the directivity of the directional couplers.