Abstract: Multiphase series capacitor DC-DC converters are provided, including: a power stage circuit configured to convert an input DC voltage into a stable DC voltage required by a load, where the power stage circuit includes inductors of two or more phases, and there is a phase difference with a preset interval between inductor currents of phases for alternately charging the load in sequence, and a bidirectional switch is provided between inductors of every two adjacent phases, where when the bidirectional switch is turned on, the inductors of the corresponding two phases charge the load simultaneously; and a load transient response circuit configured to, when a load transient positive step occurs, control one or more bidirectional switches to be turned on to make inductors of two or more corresponding phases charge the load simultaneously. Control methods of such converters are also provided, which can realize fast response to load transient changes.

Abstract: An apparatus includes a controller. The controller monitors a magnitude of first current supplied by an output voltage of a first power converter to power a dynamic load. The controller controls a second power converter to supply second current through the dynamic load based on the monitored magnitude of first current.

Abstract: A system includes a load and a switching converter coupled to the load. The switching converter includes at least one switching module and an output inductor coupled to a switch node of each switching module. The switching converter also includes a controller coupled to each switching module, where the controller is configured to adjust a pulse clock rate and a switch on-time for each switching module. The controller comprises a pulse truncation circuit configured to detect a voltage overshoot condition and to truncate an active switch on-time pulse in response to the detected voltage overshoot condition.

Abstract: In reading of a memory unit, an read failure operation due to variation in characteristic of a transistor in a dynamic load is reduced. A read circuit that reads a voltage obtained by a voltage division of a dynamic load unit and the memory unit as an output of the memory unit includes the dynamic load unit having one end connected to a side of a power supply and the other end connected to a side of the memory unit, and a feedback unit that, by a feedback of the voltage obtained by the voltage division that is divided between the dynamic load unit and the memory unit, holds the voltage obtained by the voltage division. The dynamic load unit has an array structure in which a plurality of resistive memory elements are connected in series, in parallel, or in series-parallel. The dynamic load unit has the array structure of the resistive memory elements and this structure can suppress the read failure operation due to the variation in dynamic load.

Abstract: A resonant power conversion device includes: series-connected filter capacitors disposed at an input side and transformers, a power conversion circuit disposed between a primary side of the transformer and the filter capacitor, and a power conversion circuit disposed between a primary side of the transformer and the filter capacitor. The resonant power conversion device further includes: an adjustment amount calculator for calculating an adjustment amount indicating a delay time of a rise of a pulse of a control signal to a switching element or a switching element in accordance with a voltage difference between the filter capacitors; and a controller for, in accordance with the adjustment amount, causing a delay in the rise of the pulse of the control signal to the switching element or the switching element, and outputting the rise-delayed control signal to the switching elements.

Abstract: A voltage regulator includes a plurality of output stages and a controller. The plurality of output stages are arranged for selectively enabling to generate output voltages and output currents or not according to a plurality of control signals, respectively. The controller is arranged for sensing the output currents of the output stages, and generating the control signals according to the sensed output currents. When the controller generates the control signals to reduce a quantity of the enabled output stages, the controller determines whether a summation of the sensed output currents is greater than a first threshold or not to determine whether to enable more output stages, then a period of time later, the controller selectively determines whether the summation of the sensed output currents is greater than a second threshold or not to determine whether to enable more output stages, wherein the second threshold is lower than the first threshold.

Abstract: An electronic device adapted for adjusting a light effect of a CCFL is provided. The electronic device is electronically connected to the CCFL. The electronic device comprises a PWM controller configured to receive at least a digital signal and to output a specific-frequency reference signal according to the digital signal, a driver electronically connected to the PWM controller and configured to output a first voltage signal according to the specific-frequency reference signal, and a transformer electronically connected to the driver and the CCFL. The transformer amplifies the first voltage signal to generate a second voltage signal and sends the second voltage signal to the CCFL. A light effect is generated by the CCFL according to the second voltage signal.

Abstract: A soft start circuit accepts an input of a reference voltage set arbitrarily, and generates a soft start voltage that takes a predetermined sweep time to slowly rise from a predetermined lowest value to a highest value that is higher than the reference voltage and changes in accordance with the reference voltage.

Abstract: A boost control section for controlling a converter includes a PI control section and a resonance suppression section. The PI control section calculates a basic command value based on a deviation between a drive voltage generated by the converter and a target voltage to equalize the drive voltage and the target voltage. The resonance suppression section calculates, based on the state of variation of the drive voltage, a correction value for correcting the basic command value to suppress the variation. The basic command value is corrected by adding the correction value. First and second drive pulses corresponding to the corrected command value are outputted to the converter.

Abstract: The present invention provides a synchronous regulation circuit for turn-on and turn-off phase angle of the AC voltage, wherein a solid switch unit is installed between an AC power source and a load, and a phase angle regulation circuit is utilized to synchronously regulate both of the turn-on phase angle and turn-off phase angle of the solid switch unit, so that the sine waveform voltage of the AC power source can be kept to output in symmetrical waveforms within the range in which the turn-on and turn-off phase angles being synchronously regulated.

Abstract: In an induction motor group control system, magnetic energy recovery switches (3) are connected in series to an induction motor (2) directly driven by a commercial power supply, and a plurality of induction motor control devices (10) enabling voltage control and reactive power control of the induction motor 2 are employed to control generation of reactive power so as to maximize a power factor of the entire plurality of AC loads including the induction motor or compensate variations in voltage of an AC power supply (1).

Abstract: An electricity generation device includes a permanent-magnet electric generator with three or more phase windings each having an output terminal and connected to a neutral point, and bidirectional semiconductor switching circuits capable of interrupting connections between the respective phase windings and the neutral point. Each switching circuit allows current to flow in both directions. A gate signal generation circuit outputs to one of the switching circuits during a period including the time at which the AC voltage excited in the corresponding phase winding turns from positive to negative and during a period including the time at which the AC voltage excited in the corresponding phase winding turns from negative to positive. A startup gate signal output circuit outputs a startup gate signal to all of the bidirectional semiconductor switching circuits when the permanent-magnet electric generator is to be started.

Abstract: The present invention provides a synchronous regulation circuit for turn-on and turn-off phase angle of the AC voltage, wherein a solid switch unit is installed between an AC power source and a load, and a phase angle regulation circuit is utilized to synchronously regulate both of the turn-on phase angle and turn-off phase angle of the solid switch unit, so that the sine waveform voltage of the AC power source can be kept to output in symmetrical waveforms within the range in which the turn-on and turn-off phase angles being synchronously regulated.

Abstract: A control circuit for a switch unit of a clocked power supply receives an auxiliary signal from a resonant transformer driven by the switch unit and detects reference crossing moments when the auxiliary signal crosses a reference value. A driver is controllable to switch the switch unit, and a synchronization circuit synchronizes a turn-on of the switch unit within a predetermined time interval around a zero crossing of a voltage present across the switch unit, or of a current flowing through the switch unit. The synchronization circuit receives information about the reference crossing moments and provides a turn-on signal to the driver with a fixed phase delay at the reference crossing moments, so as to define turn-on moments at which the driver is to turn on the switch unit.

Abstract: The alternating voltage control apparatus which is inserted serially between an alternating-current power source and an inductive load and which controls adjustment of load voltage of the inductive load with a magnetic energy recovery switch reduces a voltage burden of a reverse conduction type semiconductor switch within the magnetic energy recovery switch and a capacitor and controls voltage to be supplied to the inductive load with a small advancing amount of a phase of current to be supplied to the inductive load.

Abstract: A switching regulator includes a first switching regulator corresponding to a master channel, and a second switching regulator corresponding to a slave channel. The first switching regulator generates first output voltage Vout1 by a constant on-time system in which on-time is constant. On the other hand, the second switching regulator monitors a first switching signal and a second on-time control circuit determines on-time of a second switching signal in accordance with lapse time from the rising time of the first switching signal to the rising time of a second switching signal.

Abstract: A method is provided for controlling a converter of the multiphase interleaving type. According to the method, there is detected when a change of a load applied to an output terminal of the converter occurs. When detected, all of the phases of the converter are simultaneously turned off by the generation of suitable PWM driving signals. The PWM driving signals are controlled so as to force the turn-on of the phases at the same time and to zero a time phase shift of driving of the interleaving type of the PWM driving signals. The interleaving of the driving time phase shift is recovered and a normal operation of the converter is restarted. A controller for controlling a converter of the multiphase interleaving type is also provided.

Abstract: The invention involves a control circuit for a switch unit of a clocked power supply circuit, the switch unit being designed to effect input-side excitation of a resonant transformer arrangement, and comprises an input for receiving an auxiliary signal from the resonant transformer arrangement. The invention also includes a resonance converter that enables independent control of frequency and turn-on moments, or duty cycle, and thus enables a particularly efficient operation of the resonance converter, and a particularly precise regulation.

Abstract: A switching regulator includes a first switching regulator corresponding to a master channel, and a second switching regulator corresponding to a slave channel. The first switching regulator generates first output voltage Vout1 by a constant on-time system in which on-time is constant. On the other hand, the second switching regulator monitors a first switching signal and a second on-time control circuit determines on-time of a second switching signal in accordance with lapse time from the rising time of the first switching signal to the rising time of a second switching signal.

Abstract: A time delay synchronous control scheme for a power supply, which has multiple outputs and tight output regulations, is provided. The switching mode power supply includes (1) a front-end DC/DC converter with current mode output, which can be a LLC Series Resonant converter (SRC) or a flyback converter; (2) one or several post buck converters directly cascaded from the output capacitor of the front-end DC/DC converter; (3) a new scheme of time delay synchronous control used to make the post buck synchronize and modulate from the front-end LLC-SRC or flyback converter. The proposed time delay synchronous control circuit can eliminate the conventional input filter of the post buck converters, as well as reduce the ripple current on the output capacitor of the front-end DC/DC converter, as a result of which, a high efficiency for the overall architecture can be obtained.

Abstract: The present invention provides a synchronous switching control circuit for variable switching frequency power converters. It comprises a first circuit to generate a first signal in response to an input synchronous signal of a power converter. A second circuit is coupled to the first circuit to generate a second signal in accordance with the frequency of the first signal. Only when the first signal is operated in a specific frequency range, the synchronous operation is allowed. An oscillation circuit is connected to the first circuit and the second circuit to receive the first signal and the second signal to generate an oscillation signal. The oscillation signal is utilized to enable the switching signal of the power converter. The switching signal is thus synchronized with the input synchronous signal in response to the enable of the second signal. Otherwise, the switching signal will be free running.

Abstract: A power supply device in a semiconductor memory includes a power control means and a power generation means. The power control means divides a self-refresh section into an active-precharge mode and an idle mode depending on an operation characteristic of the semiconductor memory, and generates a control signal for controlling power strength applied to the semiconductor memory during operation in each mode. The power generation mode generates a different power level in response to a power control signal from the power control means to provide to the semiconductor memory. Meanwhile, the power supply device according to the present invention provides relatively strong power to the semiconductor memory a predetermined time period in advance of the active-precharge mode.

Abstract: A static electrical energy converter modulates the electrical energy exchanged between at least two electrical sources. The converter includes at least one electrical voltage source, one current source and at least one electrical switching stage, each switching stage having at least two static switches (k1) star-connected to the voltage source or voltage sources, with the common point of the star connected to the current source, and the current source being connected back to the voltage source or sources. At least one of the static switches (k1) of at least one switching stage is a switch provided with two output electrodes, of which at least one change of state (providing switching at the opening or at the closing) is automatic and is operated exclusively at a predefined voltage threshold other than zero when the absolute value of the voltage increases.

Abstract: A multiple-phase DC—DC converter adds at least one additional phase to an N-phase DC—DC converter to improve the converter's response to changes in load. In one embodiment, an additional phase operates at a switching frequency greater than that of the N phases, to generate a current which is added to the N phase currents to improve the converter's response to changes in load. In another embodiment, an additional phase is configured to improve the converter's response to a load release. Here, the additional phase is kept off during load increase and steady-state conditions. However, when a load release occurs, the additional phase is turned on and acts to extract current from the converter's output terminal while the N phase currents slowly fall, to reduce the magnitude of output voltage overshoot that occurs on load release.

Abstract: A DC/DC converter produces from an input voltage a desired output voltage by first finding the error voltage between the output voltage and a first reference voltage and then controlling the output current according to the differential voltage between the error voltage and a second reference voltage. Used as the first reference voltage is whichever of a variable reference voltage and a first constant reference voltage is lower, and used as the second reference voltage is whichever of the variable reference voltage and a second constant reference voltage is lower. With this circuit configuration, an overshoot or undershoot in the output voltage can be prevented or reduced.

Abstract: A system and method for synchronizing a remote generator to a bus, whether or not power from the bus is available at the generator. The system includes: a first clock at a host site; a host timing processor for determining the time of a synchronizing event; a communication channel for transmitting the time to a remote site; a second clock at a remote site synchronized to the first clock; and a remote timing processor for receiving the time of a synchronizing event, comparing the time of the event to the time of a similar event at the generator, and adjusting the speed of the generator to synchronize the generator to the bus.

Abstract: The invention relates to a method and an arrangement implementing the method for adjusting output power of a transmitter power supply, in which method the output power of the power supply is measured and the output power of the power supply is adjusted on the basis of the measured output power. In the method, the output power of the transmitter power supply is adjusted on the basis of the transmission power of the transmitter such that a power supply control unit receives from the transmitter a synchronization chopping that synchronizes the operation between the transmitter and the power supply control unit, and the power supply control unit receives from the transmitter the information on the transmission power of the transmitter.

Abstract: The present invention relates to a method to generate at least a supply voltage to supply energy to a hearing device, whereas the ratio between the supply voltage and the source voltage is adjustable. The hearing device substantially comprises a source (Q), at least a switching element (S1, . . . , Sn), at least an energy transfer element (EUE), at least an energy storing element (ES), a load (Z) and a control unit (CTRL), whereas the method consists in that, in a first step, the control unit (CTRL) acts on the switching elements (S1, . . . , Sn), such that energy is transferred from the source (Q) to the energy transfer elements (EUE), that, in a second step, the control unit (CTRL) acts on the switching elements (S1, . . . , Sn), such that at least a part of the energy stored in the energy transfer elements (EUE) is transferred to the energy storing elements (ES) to build a supply voltage across the load (Z).

Abstract: An output voltage of a rectification smoothing circuit is compared with a reference voltage. When a reduction in the output has been detected, an A/D converting circuit converts a result of the comparison which is negatively fed back by an output voltage feedback circuit to obtain a control signal for a bidirectional switch element inserted into a primary side of a transformer so as to turn ON or OFF synchronously or asynchronously with a commercial power supply via an intermittent control circuit.

Abstract: The present invention relates to a method to generate at least a supply voltage to supply energy to a hearing device, whereas the ratio between the supply voltage and the source voltage is adjustable. The hearing device substantially comprises a source (Q), at least a switching element (S1, . . . , Sn), at least an energy transfer element (EUE), at least an energy storing element (ES), a load (Z) and a control unit (CTRL), whereas the method consists in that, in a first step, the control unit (CTRL) acts on the switching elements (S1, . . . , Sn), such that energy is transferred from the source (Q) to the energy transfer elements (EUE), that, in a second step, the control unit (CTRL) acts on the switching elements (S1, . . . , Sn), such that at least a part of the energy stored in the energy transfer elements (EUE) is transferred to the energy storing elements (ES) to build a supply voltage across the load (Z).

Abstract: A DC-DC convertor is used as a power source for an electronic apparatus. In this converter, a synchronous rectification transistor is provided in parallel with a flywheel diode. A control circuit of the converter is configured in such a way that a synchronous rectification transistor isolating unit for compulsorily turning off the synchronous rectification transistor for a predetermined fixed period of time, at the activation time of the DC--DC convertor, is included.

Abstract: In a partitioned power converter system having a central uninterruptible power supply ("UPS") stage couplable between a commercial power source and a peripheral stage, the central UPS stage including a primary converter that converts commercial power from the commercial power source to a distribution voltage; a battery boost converter, coupled to a battery reserve system, that boosts a battery voltage produced thereby to the distribution voltage; and mode switching circuitry that alternatively couples one of the primary converter and the battery boost converter to the peripheral stage, selective bypass circuitry and a method of increasing the efficiency of the power converter system.

Abstract: An apparatus and method is provided for controlling electrical power from a power source to electrical loads in response to a decrease in power source voltage. A power source signal is compared to a predetermined signal voltage to determine whether and how much the voltage of the power source signal has decreased below that of a predetermined signal. A fraction of electrical power from the power source is transmitted to the loads as a function of how much the voltage of the power source signal has decreased below that of the predetermined signal.

Abstract: An A.C. power supply controller for a capacitive load such as an array of electroluminescent panels (1) having circuit elements (10 to 15) for producing a pulsed switching waveform (p) centered on the zero-crossing points (z) of an applied alternating voltage waveform, powerswitch (17) for connecting the applied voltage waveform or another voltage waveform to the load in response to the pulsed switching waveform (p), and control elements (5) for widening the pulse width of the switching waveform (p) symmetrically about the zero-crossing points (z) to vary the power applied to the load. The circuit elements (10 to 15) includes a rectifier (10) that rectifies the applied alternating voltage waveform, and a comparator (13) that compares the rectified waveform with a control D.C. input level (15) to produce an output level between adjacent crossing points of the two signals about the zero-crossing points (z). A linear potentiometer varies the D.C. input level (15).

Abstract: A method for regulating the power in a load connected to the mains through a controlled switch and a device for implementing the method. The method includes the following steps: detecting a mains synchronization pulse, which determines the start of a cycle, within a fixed time interval of the preceding cycle; as soon as the pulse has been detected, waiting for the end of the fixed interval, then counting down a first time interval that substantially corresponds to a selected time interval; at the end of the first time interval, triggering the switch on and counting down a second time interval that ends before the normal arrival of the next synchronization pulse; and at the end of the second time interval, counting down the fixed time interval within which the next synchronization pulse must be detected.

Abstract: A circuit array, adapted to be coupled to a load and a source of a main AC voltage, for reverse phase angle control whereby a current flow in the load is limited to a defined phase angle (.alpha.) of the main AC voltage, comprising the following components for sequential control of the reverse phase angle control: a switching element, connected to the load and coupled to the source of the main AC voltage, for actuating the current flow in the load; a time determining component; and an integrated circuit.

Abstract: The operation of an electromechanical relay is synchronized with the power line waveform where an electrical power supply is supplied from a source to an electrical load. The current voltage supplied to the load is characterized by a power line waveform. An electromechanical relay is positioned between the power supply and the load where contacts of the relay are opened and closed to interrupt and supply power to the load. A microcontroller is positioned between a power source and the electromechanical relay and actuates the relay so that when the contacts are closed or opened the contacts are not exposed to an undesired voltage. A feedback control circuit senses the opening and closure of the contacts so that in the event the contacts, for example close at an undesireable point on the load current waveform the microcontroller adjusts for the necessary delay to cause the actuation of the relay to occur such that the contact closure is at the desired point in the load current waveform.

Abstract: A power supply (100) includes an energy source (102) which provides cyclically varying supply voltage having periodic repeated beginning points. Generally, the beginning points comprise zero potential points of the cyclically varying supply voltage. The energy source is coupled to an energy control means (106) which is responsive to a control setting for controlling an output (108). A controller (114) provides the control setting in response to a feedback signal received from a sensor (116) only at the beginning points and maintains control of the control setting constant until a subsequent beginning point.

Abstract: A method and circuit for reverse phase control of alternating current being delivered to a load are disclosed wherein voltage-controlled semiconductor switches, such as MOSFET's and IGBT's, are used as electronic switches to conduct voltage during the leading edge of the AC voltage cycle and conduction is terminated when the desired phase angle of the current flow has been reached. The disclosed method and circuit eliminate the need for zero crossing detection of the AC waveform and ensure that the voltage-controlled switches are always turned on before the zero crossing thereby minimizing radiated interference and incandescent lamp hum. The method used is primarily digital in nature making mechanical input or electronic input for the power control equally efficient to implement.

Abstract: Circuitry and methods are provided for AC line synchronization of the firing means for phase-controlled thyristors in a DC motor speed control system. A line synchronization method and system is disclosed which eliminates zero offset in the phase command input function. This zero offset, which is cuased by motor counter EMF, occurs in prior art controllers which use zero crossings of the AC line voltages for line synchronization of thyristor firing. This invention provides line synchronization timing intervals of constant duration that terminate at the coincidence of AC line voltage and motor counter EMF with the coincidence being the latest time at which the particular thyristor being controlled is forward biased in the absence of current flow. Application to N-phase AC to DC converters for DC motor speed control is disclosed.

Abstract: A controller can control controlling a precipitator. The controller has a power modulator. The modulator has a control terminal and is coupled to the precipitator. The power modulator is adapted to be powered by an alternating current. The modulator can operate to regulate the drive to the precipitator in response to a control signal on the control terminal. The controller also has a measurement means coupled to the precipitator for providing a plurality of measurement signals corresponding to a plurality of operating parameters of the precipitator. Also included is a processing means having a program. The processing means is coupled to the measurement means and the power modulator for producing the control signal and for regulating the power modulator in response to the measurement signals.

Abstract: A pair of static induction thyristors, which are coupled in parallel in the opposite bias directions between an AC power source and a load, is turned on by a light signal and is turned off by natural commutation, a light signal or an electric signal. The turn-off light signal is generated within a phase angle of 90.degree. in the time axis around the zero-cross point of the AC voltage from the AC power source.

Abstract: The invention relates to a temperature control method and to a temperature control circuit. In a measured value detecting member (2) a measuring voltage (U.sub.TH) is generated which is representative of the actual temperature. In an adjustment member (1), a desired voltage (U.sub.S) is generated which is representative of the desired temperature. A difference former (inverse adder 5) determines from the measuring voltage (U.sub.TH) and the desired voltage (U.sub.S) a deviation voltage (U.sub.D) which corresponds to the deviation between the desired temperature and the actual temperature. The heating power of the heating element (14) of the temperature control circuit is regulated proportionately in dependence on the deviation voltage (U.sub.D) by shifting the phase angle (.phi.). During each line half-wave (27), the deviation voltage (U.sub.D) is compared in a comparator (comparator 11) with the descending edge voltage of a line-synchronous delta voltage (U.sub.DS).

Abstract: In a microcomputer-based multi-function thyristor-controlled AC induction motor drive, the microcomputer effectuates the several control functions of the motor drive during respective time intervals corresponding to the sequence of firing of the thyristors, and upon each new time interval, depending upon the required delay angle, firing is effected as a function of a residual angle in terms of a multiple of said time intervals, and the firing sequence is shifted by an amount of time intervals in relation to the integer number of such time intervals within such delay angle. As a result, firing of the thyristor is performed by the microcomputer without impeding control function determination and with improved response to change in the delay angle.

Abstract: Power from an AC source is applied to a load under control of a power switching triac in response to signals from a feedback loop isolated from line voltage transients by means of a pair of opto-coupling devices respectively connecting the feedback loop to a load voltage sensor and the control electrode of the triac.

Abstract: Multiplexing apparatus interconnects at least one power switching device, itself connected to a load for controlling of flow of current through that load from an AC source, with a control circuit for controlling conduction of the switching device(s). The multiplexing apparatus uses a full-wave rectifier for providing both half-cycles of the source AC signal waveform, transformed to have a common preselected polarity, with a first DC level to obtain zero crossing information for determining the start of switching device conduction. The same comparator is utilized with a level switch, now providing a second DC level, and a resistive divider for attenuating the voltage across the conducting switching device by a known factor, for monitoring the switching device saturation voltage during conduction. The apparatus may also include a power supply subcircuit, for providing an operating potential to a completely integrated semiconductor circuit containing this apparatus.

Abstract: A control circuit arrangement for an electromagnetically operated power tool has a primary circuit including a solenoid and a semi-conductor switch, in series, the semi-conductor switch being capable of being triggered into a conducting state upon application of a trigger signal from a trigger control circuit. The trigger control circuit is actuated upon closure of a main trigger switch which is connected in series with the solenoid and the semi-conductor switch in the primary circuit for supplying current to the solenoid. Thus, should the semi-conductor switch fail due to a short-circuit, the power supply is disconnected from the solenoid the moment the operator releases the main trigger switch so protecting the solenoid. The semi-conductor switch is preferably a thyristor. An additional circuit is preferably provided for preventing the thyristor from firing a second time if the main switch remains closed.

Abstract: A standard, unmodified AC induction motor has its stator winding energized from a sine wave power source through a signal-responsive wave modifier operative to control the portion of each cycle of the sine wave which is coupled from said source to the stator winding. Load detecting means, comprising a comparatively small AC generator coupled to the rotor of the motor, produces a control signal, varying with variations in the load on the motor, for controlling the wave modifier to increase the field density of the stator winding with increases in load on the motor, and to decrease the field density of the stator winding with decreases in said load.

Abstract: A digital control unit for a static converter contains a binary-coded counter which counts the pulses of an oscillator. The counter outputs are connected to the address inputs of a function memory in which sawtooth or ramp functions are stored. The numbers read out of the function memory are compared in a comparator, with a number determining the drive of the static converter. The result of the comparison and pulses on selected outputs of the counter are linked, in a logic circuit, to form firing pulses for the static converter. The invention is suitable for control units for static converters, in particular for AC control elements and inverters. All expense of adjusting, and all compensation of drift errors is obviated.

Abstract: A phase control device for use in a phase control circuit, which forms a comparison signal synchronous with an a.c. power source, then compares this comparison signal directly with a preset phase control angle signal, and controls a phase control element provided in the a.c. phase control circuit by the compared output.