Abstract: In a capacitor charging apparatus, an on-time in which the primary circuit of a transformer is energized is continued until a primary current detection signal reaches a predetermined peak detection level, and an off-time in which the primary circuit is de-energized is clocked from the time when the primary current peak detection signal is received. At the end of the clocking, an ending signal is generated to terminate the off-time. The length of an off-time is inversely proportional to the charging voltage across the capacitor. The length of an off-time may be altered using a regulation resistor. Thus, an on-time and an associated off-time of the primary circuit of the transformer are controlled independently to optimize charging time and power efficiency of the charging.

Abstract: A constant-voltage circuit includes a switching regulator and a series regulator each configured to start operating according to a selection signal input from outside the integrated circuit for exclusively causing one of the switching or the series regulators to operate, convert an input voltage to a rated voltage and to output the voltage to an output terminal. The switching regulator performs a soft-start operation for raising an output voltage to the rated voltage at a constant speed when starting operation. The series regulator regulates a current so that an output current does not exceed a predetermined value, simultaneously starts operating when the switching regulator starts operating, and automatically stops outputting a current to the output terminal when the soft-start operation is completed. A semiconductor apparatus provided with a predetermined function includes the constant-voltage circuit. A control method controls the constant-voltage circuit.

Abstract: A control circuit for controlling a switching element in a switching power supply by generating a switching signal is disclosed. The control circuit may include a soft start circuit that generates a switching signal so that an output voltage of the switching power supply gradually increases for a period until the output voltage reaches a predetermined reference voltage. The soft start circuit may increase the output voltage at a first limiting speed when the output voltage is lower than a predetermined threshold voltage, and may increase the output voltage at a second limiting speed which is set higher than the first limiting speed when the output voltage is higher than the threshold voltage.

Abstract: In one embodiment, an apparatus is provided for a system including an integrated circuit coupled to a node to receive a supply voltage and having bypass capacitors coupled in parallel with the integrated circuit to the node. The apparatus comprises a first capacitor, a switch coupled to the first capacitor, and a voltage source configured to charge the first capacitor. The switch is coupled to receive a control signal that is asserted, during use, if the supply voltage to an integrated circuit is to be increased. The switch is configured to electrically couple the first capacitor to the node in response to an assertion of the control signal. When electrically coupled to the node, the first capacitor supplies charge to the bypass capacitors. A system comprising the apparatus, the node, the integrated circuit, and the bypass capacitors is also contemplated in some embodiments.

Abstract: A power converter for and method of producing a monotonic rise in output voltage at start-up. In one embodiment, the power converter includes a switch and an error amplifier coupled to an output terminal of the power converter. The power converter also includes a comparator with an output terminal coupled to a control terminal of the switch and an input terminal coupled to an output terminal of the error amplifier configured to enable the switch to conduct for a duty cycle. Additionally, the switch is configured to be turned off at a start-up of the power converter until a voltage of the output terminal of the error amplifier provides a duty cycle for the switch corresponding to an output characteristic pre-charge condition.

Abstract: In an information handling system, a multi-phase electrical converter includes an electrical input, an electrical output, a plurality of converter phases coupled with the electrical input and the electrical output, and a controller to ramp operation of one or more of the converter phases as a load demand adjusts. In an embodiment the converter may be a multi-phase buck converter having a high side switch, a low side switch, and an inductor. In an embodiment, the controller may ramp operation of the converter phases by adjusting a duty cycle of the high side switch. In an embodiment, the controller may adjust a phase angle of one or more of the converter phases, wherein the adjustment may be relative to the ramping operation of the one or more of the converter phases.

Abstract: There is provided a control circuit including a sampling controller configured to sample an output voltage of a power converter at an appropriate time slot by opening a control loop. A soft-start circuit configured to enable soft-starting of an internal soft-start reference voltage to start from the sampled output voltage and to control the internal soft-start reference voltage to a predetermined target value in order to pre-charge the output voltage close to an input voltage level, or to continue charging the output voltage to a predetermined output voltage value.

Abstract: One embodiment of the present invention includes a system for providing a soft-start for a power regulator comprising a differential transistor pair that receives an input current and conducts a first current through a first transistor and a second current through a second transistor. One of the first and second current changes in response to a change in the other to maintain a sum of the first and second current being substantially equal to the input current. The system also comprises a comparator that provides an output signal based on a comparison of a first input voltage and a second input voltage associated with the first current and the second current, respectively. The system further comprises a current source activated by the output signal to charge a capacitor that increases a soft-start reference voltage associated with control of the power regulator and which controls the change in the other of the first and second current.

Abstract: A method for controlling start time series by stages adopted for use on a power supply consisting of a main power system and a standby power system. The power supply includes an energy storage unit to store a judgment power. The method mainly includes: setting a start voltage, setting a boosted voltage, getting a judgment power voltage and detecting whether the judgment power has reached the start voltage or the boosted voltage, and alternately starting the standby power system and the main power system. Thus the main power system and the standby power system are started at different time series. In terms of the energy storage unit the load increases by stages. Therefore the energy storage unit can be charged to increase the judgment power voltage and increase loading by stages. As a result, inrush current also rises by stages and can be harnessed as desired.

Abstract: A switching mode power supply and method for generating a bias voltage is described. The bias voltage is generated by using a current source coupled to a primary coil of a transformer during the start-up of the switching mode power supply. The generation of the bias voltage through the current source is stopped at a second time, a delay time after a first time when the bias voltage becomes essentially equal to a reference voltage that is an operational voltage of a PWM controller. The switching operation of a main switch is started after the first time, when the bias voltage exceeded the operational voltage. In this interval the bias voltage is also generated by the secondary coil of the transformer.

Abstract: A circuit is provided including an output stage with a pair of transistors. Further provided is a control circuit in communication with the output stage. The control circuit is capable of controlling a duration in which at least one of the transistors is actuated for reducing an in-rush current.

Abstract: An electric current flowing to an upper side power MOSFET during soft-start is detected according to an on-voltage of the MOSFET and an on-pulse width of a PWM pulse for driving the upper side power MOSFET is forced to be reset in the idle and decided according to a signal generated when the voltage falls below a predetermined specified voltage.

Abstract: A soft start circuit is connected to a pulse width modulation controller including an oscillator, and a functionality of modulating amplitude to a pulse width and a power supply includes the soft start circuit. The soft start circuit includes a frequency controlling unit, a duty ratio establishing unit, and a variable switching unit. The frequency controlling unit generates first and second parameter signals for determining a frequency signal frequency by a power source from the PWM controller and provides them to the PWM controller. The duty ratio establishing unit generates a third parameter for determining amplitude of the frequency signal generated by the PWM controller according to a reference voltage, and provides it to the PWM controller. The variable switching unit determines whether it is a first predetermined time from a start-up state, and controls the first parameter of the frequency controller during the first predetermined time.

Abstract: A control apparatus for a power conversion circuit and a control method thereof are provided. The method of the control apparatus includes producing a first control signal and a second control signal; modulating the first control signal according to an output voltage of the power conversion circuit; detecting the output voltage of the power conversion circuit to attain a detecting result; if the detecting result exhibits the input voltage of the power conversion circuit below a normal operating level, using the second control signal to control the power conversion circuit; or if the detecting result exhibits the input voltage of the power conversion circuit above the normal operating level, using the first control signal to control the power conversion circuit. The duty cycle of the fist control signal is greater than that of the second control signal.

Abstract: In one embodiment, a soft-start circuit is configured to form drive pulses that increase in width independently of the current through the power switch during a first portion of the soft-start operation period.

Abstract: A power supply apparatus having a soft start function that enables a startup without any overshoot within an appropriate startup time regardless of whether the load is heavy or light. Even when output direct current voltage Vo has not yet risen upon startup, switch circuit 4 is turned ON within a count time of timer 7, and clamping circuit 5 clamps error signal Ve of error amplifier 2, so that an excessive signal is prevented from entering PWM circuit 6, and electric power supplied to load 13 is controlled. Consequently, supply power as the power supply apparatus is limited, and any inrush current can be prevented from being generated. By controlling the count time of timer 7 when this error signal is clamped, it is possible to realize a startup within an appropriate startup time without any overshoot.

Abstract: A DC-DC conversion circuit is configured by including a plurality of control signal generation circuits, a plurality of soft-start control circuits, and a start control circuit. The plurality of control signal generation circuits correspond to the plurality of control signals, and generate a corresponding control signal of the plurality of control signals based on a corresponding output value of a plurality of output values. The plurality of soft-start control circuits correspond to the plurality of control signals, and control a variation of the corresponding control signal at a start time of the DC-DC conversion circuit. The start control circuit instructs the corresponding soft-start control circuit to start operation in accordance with a change of the control signal taking part in an output control at the start time of the DC-DC conversion circuit.

Abstract: An adjustable shunt regulator comprises an operational amplifier, a transistor having a base terminal operatively connected to the output of the operational amplifier, a diode operatively connected in parallel with the transistor, and a voltage reference connected to the inverting input of the operational amplifier. The operational amplifier provides an output signal at the output thereof that corresponds to a difference between an input signal applied to the non-inverting input and the voltage reference. The output signal controls a voltage between the collector and emitter. A current source is operatively connected to the inverting input of the operational amplifier, and a capacitor is operatively connected to the inverting input of the operational amplifier in parallel with voltage reference. Upon a start-up condition of the shunt regulator, the capacitor is charged by current supplied by the current source causing the voltage reference to be limited to a charge voltage of the capacitor.

Abstract: A control circuit for controlling a switching element in a switching power supply by generating a switching signal is disclosed. The control circuit may include a short start circuit that generates a switching signal so that an output voltage of the switching power supply gradually increases for a period until the output voltage reaches a predetermined reference voltage. The soft start circuit may increase the output voltage at a first limiting speed when the output voltage is lower than a predetermined threshold voltage, and may increase the output voltage at a second limiting speed which is set higher than the first limiting speed when the output voltage is higher than the threshold voltage.

Abstract: A polyphase AC induction motor is connected to a power supply through a soft starter having three sets of inverse parallel connected silicon controlled rectifiers with each set corresponding to one particular phase. Low speed starting and operation of the motor can be accomplished through triggering circuits controlling the phases of the triggering pulses in relation to the phases of the supply. The low motor speeds are developed by a gating sequence that generates a low frequency waveform that is less than the main supply frequency to the motor. This low frequency waveform is current and voltage controlled by the gating sequence to permit the AC motor to smoothly operate at speeds less than 100% of rated while developing net positive torque at the low controlled operating frequency.

Abstract: In a lighting apparatus for a discharge lamp, a mask signal against a re-arc voltage is correctly generated to detect a lamp voltage accurately in view of a support to high frequency lighting such that the detection of the lamp voltage is not affected by the re-arc voltage. The lighting apparatus for the discharge lamp comprises a DC-AC converter for receiving an input voltage from a DC power supply to convert the input voltage to an AC voltage; detecting means for detecting a lamp voltage associated with a discharge lamp or a lamp voltage and a lamp current; and a signal generator circuit for generating a mask signal for excluding a re-arc voltage, which occurs at the time the polarity is inverted, from items to be detected, in the event of a detection of the lamp voltage. The signal generator circuit detects the lamp voltage or lamp current or a voltage at an output stage of the DC-AC converter to correctly capture a polarity inversion timing to generate a mask signal against the re-arc voltage.

Abstract: A switch mode power converter that limits the in-rush current at start-up and reduces the occurrence of output voltage overshoot over a range of switching frequencies. The converter includes at least one Soft-Start (SS)/Frequency-Select(FS) input, at least one oscillator enable input, and an oscillator having at least one control input. Soft-start programming is linked to the frequency selection of the converter. An external capacitor connected between the SS/FS input and ground is employed to program the soft-start time, and the switching frequency generated by the oscillator is selected via the state of the SS/FS input.

Abstract: In a power supply apparatus, a switching circuit selectively applies one of an input voltage of a power converting circuit and an output voltage of the power converting circuit to a voltage reducing power supply circuit. When the input voltage is applied to the power converting circuit, the switching circuit selects this input voltage, so that the output voltage of the voltage reducing power supply circuit can quickly rise. Thereafter, when the output voltage of the power converting circuit exceeds this output voltage, the switching circuit selects the output voltage of the power converting circuit. As a result, a difference between the input voltage and the output voltage of the voltage reducing power supply circuit is decreased. Thus, a power loss is lowered and noise produced in the power converting circuit is suppressed.

Abstract: A soft start circuit for a DC-DC converter has an input reference voltage coupled to an error amplifier and to a soft start capacitor. A feedback resistor is coupled between an output node and the error amplifier, whose output is coupled to a pulse width modulator (PWM). The PWM output is coupled through an inductor to the output node, to which an output capacitor referenced to ground is coupled. Means is provided to charge up the soft start capacitor to the output voltage while the converter is disabled. As a result, when enabled, the converter will not discharge the output capacitor, but will ramp the output voltage to the voltage Vref without excessive currents.

Abstract: A system and method for reducing inrush current in an information handling system includes charging a pre-charge circuit with an elongated pin. The information handling system includes a midplane with at least one power source connector and multiple blade connectors able to connect to blade servers. Each blade connector has an elongated pin for supplying power to a blade server. Each blade server has a power connector for receiving the elongated pin and an integrated pre-charge circuit including a resistor and capacitor.

Abstract: A heater energization control circuit includes a heater, a power source that supplies an alternating current to the heater, a first capacitor that charges and discharges in accordance with a first time constant that is determined by an electrostatic capacity of the first capacitor and a resistance value of a first resistor, and a second capacitor that charges and discharges in accordance with a second time constant that is determined by an electrostatic capacity of the second capacitor and a resistance value of a second resistor. A controller determines an energization start timing to the heater in accordance with a size relationship between a voltage of the first capacitor and a voltage of the second capacitor, and starting to supply the alternating current to the heater by the power source for supplying under this timing.

Abstract: A heater control device that prevents a flickering by driving a fixing heater in a phase controlling at a fixed phase angle for predetermined duration when an image forming apparatus starts power supplying to the fixing heater.

Abstract: A MOSFET, an op-amp, a comparator circuit, and voltage dividers with capacitors are employed in combination to effectuate a soft-start switch with current limiting. The transconductance of the MOSFET is employed so that no sense resistor is required. The MOSFET and op-amp are configured as a closed-loop feedback circuit in which the output of the op-amp is coupled to the gate of the MOSFET and the inverting input of the op-amp is coupled to the output of the soft-start switch via a voltage divider. A first RC circuit provides a voltage to the non-inverting input of the op-amp which can be triggered to gradually rise from a value close to zero to some reference voltage so as to soft-start a load. Current limiting means are effectuated by a comparator circuit and voltage dividers with capacitors.

Abstract: A MOSFET, an op-amp, a comparator circuit, and voltage dividers with capacitors are employed in combination to effectuate a soft-start switch with current limiting. The transconductance of the MOSFET is employed so that no sense resistor is required. The MOSFET and op-amp are configured as a closed-loop feedback circuit in which the output of the op-amp is coupled to the gate of the MOSFET and the inverting input of the op-amp is coupled to the output of the soft-start switch via a voltage divider. A first RC circuit provides a voltage to the non-inverting input of the op-amp which can be triggered to gradually rise from a value close to zero to some reference voltage so as to soft-start a load. Current limiting means are effectuated by a comparator circuit and voltage dividers with capacitors.

Abstract: A motor starter circuit for minimizing the amount of current drawn by the motor from a power source during starting of the motor through current transformation achieved by selectively controlling actuation of a plurality of high speed switches. The circuit is for use with a alternating current power source that provides positive and negative voltage alternations, and an alternating current motor. The motor starter circuit comprises a first bidirectional switch through which line current from the power source is provided to the motor, and a pair of switch-diode combinations electrically configured to carry the current in the motor when the bidirectional switch, which is controlled to cycle between an open and a closed position, is in an open position. Actuation of the pair of switch-diode combinations is controlled based on the polarity of the motor current alternation.

Abstract: A resonant convertor control system regulates a resonant AC current based on the amount of input power consumed by the system. The switching frequency and resonant AC current are limited by a phase difference assurance circuit that compares the phase of a drive signal with the phase of the resonant AC current. By detecting the phase of the resonant current instead of the resonant voltage, it eliminates the need for the costly components required to detect the resonant voltage. The system includes a main power supply for supplying a DC power signal and an inverter that converts the DC power signal to a resonating AC current signal responsive to a drive signal from a drive stage. An input current controller receives a first sense signal that indicates the power consumed by the main power supply and generates a first control signal that regulates the power consumed by the load.

Abstract: A motor is supplied with electricity across a transformer (T) which outputs on a busbar (J) which is connected to the motor (M) and to other electrical energy consuming devices, the motor by itself consuming an active power greater than or equal to 20% of the available electric power. During at least a part of the starting period of the motor, the motor is supplied with reduced voltages taken on intermediate taps (P.sub.1, P.sub.2, P.sub.3) in the secondary windings of the transformer (T).

Abstract: An auxiliary or ballast circuit for high-frequency operation of discharge mps (E), for example sodium high pressure discharge lamps, provides for controlled inrush or "ON current" by including a thyristor (TH1) or pair of thyristors (TH2, TH3) in the current supply path to the discharge lamp (E) integrated into a combination active filter-voltage step-up circuit. The gate of the thyristor (TH1) or a pair of thyristors (TH2, TH3) is, or are, controlled over a resistance (R2, R3, R4) connected to the output capacitor (C2) of the filter-voltage step-up circuit to fire the thyristor when input voltage goes through null, and the output capacitor (C2) has a predetermined voltage level above the input voltage. The output capacitor (C2), before firing, is charged by a charge control resistor (R1) connected in parallel across the anode-cathode path of the thyristor or thyristors.

Abstract: A MOSFET, an op-amp, a comparator circuit, and voltage dividers with capacitors are employed in combination to effectuate a soft-start switch with current limiting. The transconductance of the MOSFET is employed so that no sense resistor is required. The MOSFET and op-amp are configured as a closed-loop feedback circuit in which the output of the op-amp is coupled to the gate of the MOSFET and the inverting input of the op-amp is coupled to the output of the soft-start switch via a voltage divider. A first RC circuit provides a voltage to the non-inverting input of the op-amp which can be triggered to gradually me from a value close to zero to some reference voltage so as to soft-start a load. Current limiting means are effectuated by a comparator circuit and voltage dividers with capacitors.

Abstract: This invention relates to an electric switch intended to be placed in an electric power circuit, said switch being responsive to a control signal. The switch comprises a semiconductor switch, an electromechanical switch and a signal processor. The electromechanical switch is connected in parallel to the semiconductor switch. The signal processor receives the control signal and outputs a command signal for controlling the semiconductor switch and the electromechanical switch. The invention also relates to a process for switching an electric power circuit.

Abstract: An incandescent lamp bulb which is driven by an electronic control module (ECM) and method of manufacture characterized in that an inductor comprising a magnetic element and a winding thereon is disposed within a screw shell base of the lamp bulb and surrounds the lamp exhaust tube therein. One end of the winding on the magnetic element is connected to a filament wire within the screw shell base and the other end of the inductive winding is connected to an output terminal of the ECM control module. In this manner, the inductor significantly reduces the di/dt rise time of voltage and current when a triac within the ECM module is driven to conduction on each one half cycle of the applied AC line voltage. This operation in turn produces a substantial reduction in radio frequency interference, both of radiation transmitted into space from the lamp bulb and by direct DC coupling back into the AC line voltage source.

Abstract: An incandescent lamp bulb which is driven by an electronic control module (ECM) and method of manufacture characterized in that an inductor comprising a magnetic spool and a winding thereon is disposed within a screw shell base of the lamp bulb and surrounds the lamp exhaust tube therein. One end of the winding on the magnetic spool is connected to a filament wire within the screw shell base and the other end of the inductive winding is connected to an output terminal of the ECM control module. In this manner, the inductor significantly reduces the di/dt rise time of voltage and current when a TRIAC within the ECM module is driven to conduction on each one half cycle of the applied AC line voltage. This operation in turn produces a substantial reduction in radio frequency interference, both of radiation transmitted into space from the lamp bulb and by direct DC coupling back into the AC line voltage source.

Abstract: A transformer is energized from an a.c. source by initially applying the . voltage to the transformer during small but progressively increasing fractions of a succession of initial half-cycles. This is continued until the rated voltage is achieved or until the reactive current exceeds a predetermined value below that which would cause tripping of the transformer. In the event that the reactive current reaches the predetermined value, the remanence of the transformer is set at a selected level by applying the a.c. voltage to the transformer during an additional half-cycle. The length of exposure of the transformer to the a.c. voltage during the additional half-cycle depends upon the circumstances. Once the remanence has been set, operation of the transformer proceeds normally.

Abstract: A device runs a precheck of an inductive load for an overload prior to swhing on to supply mains. For this purpose, following switching-on for a load precheck, initially a phase limited voltage signal is applied to the load, whereby the voltage signal duration gradually increases. With the start of each application of voltage, the active current is measured in a narrow time window. If it does not exceed a predetermined active current limit at an application of a specific effective voltage, the load is switched to the mains. Otherwise, the switch-on process is cut off. This switching-on process avoids a high taxing of the mains in the event of a short circuit or an overload. The active current window begins with the application of voltage to the load. At a different time than this time window, a further measurement window is provided for the reactive current, whereby this measurement window begins with the zero crossing of the alternating voltage.

Abstract: The present invention provides a electronic switch suitable for fading on/off control of electrical equipment like lamps and motors. The main circuit comprises a rectifier bridge circuit and a thyristor. A control circuit includes a fast discharging synchronic integrator and a trigger pulse integrator, the former acts as a pulse phase shifter to provide a self-adapting magnitude variable sawtooth waveform, while the latter acts as a dynamic phase variation memory so as to provide a variable reference for comparison. Trigger pulses which are feed back via the main circuit causes the synchronic integrator to fast discharge. If a control switch is closed, the voltage on the integral capacitor and the trigger angle decreases gradually to produce the fade on. In the fade off process, the conditions are just the opposite. Fading on/off time can be independently set.

Abstract: In a window heater controlling apparatus used in an automobile, a heater control unit including a microcomputer is employed to detect a heater-ON condition and thereafter to control the heating voltage of the alternator in such a manner that the heating voltage is gradually increased up to the rated heating voltage at the beginning of the heater control operation. This heater control operation can be performed by duty ratio control of the switching transistor.

Abstract: A two-terminal, alternating current power control device connected in an electrical path between a load and a remote switch, comprising a current switching device, a controlling device and a direct current power supply device. The current switching device provides a low impedance electrical path in response to the application of triggering signals thereto, and provides a high impedance electrical path in the absence of the triggering signals. A control circuit is provided for applying triggering signals to the current switching device as the proper time in the AC cycle, and is responsive to a momentary interruption in the applied AC voltage so as to effect change in the power intensity or timed duration of power delivered to the load. A remote switch in the electircal path can be the source of a momentary power interruption.

Abstract: This invention concerns a circuit arrangement for current limiting for a.c. machines with phase gating control by solid-state devices, aimed at achieving a smooth start by arresting the steady decrease in the ignition angles upon the attainment of a predetermined limiting current value. For use with single-phase measurement of the load current, a circuit is provided for measuring the instantaneous value of the magnitude of the load current, such as a threshold-value detector, which is actuated by a single-phase full-wave rectified load current. The output of this threshold-value detector is applied to a monostable digital device.

Abstract: The present system includes a bridge circuit (with four legs) with one leg including a heating element. The mid-points of the bridge circuit are connected to a silicon controlled rectifier (SCR) which is further connected to the control element of a monostable multivibrator. Further connected to the power input elements of the monostable multivibrator is a D.C. power source. The monostable multivibrator is connected to a transistor which has a light emitting diode (LED) in its cathode circuit. The LED is part of a circuit which further includes a light sensitive triac. The light sensitive triac is further connected through a pulse generating circuit to the control element to a second triac which in turn is connected to supply heavy electrical current to the heating element.

Abstract: An AC power control apparatus including a power circuit for supplying an AC current to a load, and a circuit connected to a power supply, for initiating energization of the load at a zero-cross point of an AC current waveform. A control circuit for controlling the change of energization time between a current turn on time to a current turn off time in units of AC waveform cycles, and a detector for detecting an AC zero level. From a given polarity of the AC current waveform, the initiating energization of the load and deenergization of the load at a zero-cross point of the AC current waveform is from the same polarity as the given polarity of the AC current waveform.

Abstract: A compensation circuit includes a circuit for monitoring the current delivered to a load and for producing a switching signal whenever a current spike is detected. A control signal representative of the desired voltage across the load is produced. A power supply supplies voltage to the load in response to the control signal. The circuit for generating the control signal is responsive to the switching signal for adjusting the control signal such that when a current spike is detected the voltage delivered to the load is substantially instantaneously reduced.

Abstract: Electrical control apparatus including a power supply, a regulating element, a manually-operable control device which can be set to provide a preset output from the regulating element, and an automatic control circuit for modifying the operation of the control elements in the event of a power failure. The automatic control circuit is so arranged as to rapidly reduce the output to zero when the absolute supply voltage falls below a predetermined level, and to progressively raise the output to the preset level when the supply voltage is restored.

Abstract: A temperature-responsive circuit, for operation with a load-control apparatus having a control input for adjusting the magnitude of power applied to a load from a source, uses: a sensor responsive to the temperature in the vicinity of the load-control apparatus; a subcircuit for converting the temperature sensed by the sensor to the magnitude of an electrical parameter; a subcircuit for providing a reference electrical parameter having a magnitude predeterminately selected to equal the magnitude of the electrical parameter at a maximum desired temperature T.sub.

Abstract: The present invention provides a power supply for lighting an incandescent lamp with high-brightness, comprising connecting a time constant circuit, rectifier, switching device so that the output of the rectifier is supplied to an incandescent lamp through the impedance for a period, determined by the time constant circuit, and that the switching device conducts and shorts the impedance after a lapse of the period to allow the incandescent lamp to receive the output of the rectifier by bypassing the impedance.

Abstract: A two-terminal, alternating current power control device connected in an electrical path between a load and a remote switch, comprising a current switching device, a controlling device and a direct current power supply device. The current switching device provides a low impedance electrical path in response to the application of triggering signals thereto, and provides a high impedance electrical path in the absence of the triggering signals. A control circuit is provided for applying triggering signals to the current switching device as the proper time in the AC cycle, and is responsive to a momentary interruption in the applied AC voltage so as to effect change in the power intensity or timed duration of power delivered to the load. A remote switch in the electrical path can be the source of a momentary power interruption.