Abstract: An improved tapped-inductor boost converter for operating a gas discharge lamp is disclosed. The converter includes a pair of input terminals connected to a power source supplying an input voltage, a pair of output terminals for providing an output voltage greater than or equal to the input voltage to the lamp, or other load, a tapped-inductor having first and second windings, an active switch for controlling current flow through the first winding for variably controlling the output voltage, a passive switch for controlling current flow through the second winding, and a first capacitor. The converter further includes an arrangement for varying the clamping voltage at the active switch in response to variations in the output voltage and also includes a clamping capacitor for transferring energy stored in the leakage inductance of the tapped-inductor to the load for improved efficiency.

Abstract: Disclosed is a novel lighting device comprising a power source capable of supplying to an argon lamp a voltage exceeding its rating, and an argon lamp connected with an output terminal of said power source. Argon lamp emits a natural light when lighted by energizing a voltage exceeding the rating. Such a light has superior color rendering properties, as well as a color temperature of about 2,900.degree. K. or higher which is very close to that of that of early morning sunlight. Thus, the lighting device is advantageously used in luminares in general.

Abstract: A variable voltage regulator for incrementally regulating an input signal. The regulator includes a diode configuration which allows incremental reduction or clamping of an AC or DC input signal. Such a universal diode configuration has widespread use in many different voltage regulating applications, either as an integrated circuit or in discrete component form.

Abstract: An electrical circuit used in conjunction with high power factor ballasts and quality fluorescent lamps to reduce the power consumption of a fluorescent fixture by an average of 40% with a lesser reduction of light output because of optimized current control through the discharge lamps increasing the efficacy of conversion of electricity to light, accomplishing this by means of a tuned inductor-capacitor resistor circuit, these along with a 1 to 1.3 impede current surges, transformer, add harmonics a circuit diode and feedback loop to reshape the circuit waveform for optimum performance of said lamps and optimum economic savings and payback through applicaiton of this technology to multiple fixtures in offices, factories, commercial buildings and stores.

Abstract: In an inverter-type fluorescent lamp ballast adapted to be powered from a DC supply voltage consisting of a substantially non-filtered full-wave-rectified 60 Hz power line voltage, the inverter's output is a 120 Hz magnitude-modulated squarewave voltage of frequency controllable about 30 kHz. The magnitude-modulated squarewave voltage is applied across a series-connected high-Q L-C circuit. The fluorescent lamp is connected in parallel with the tank capacitor of this L-C circuit. The magnitude of the current drawn by the fluorescent lamp is a sensitive function of the frequency of the squarewave voltage and is controlled by correspondingly controlling the frequency of this squarewave voltage.

Abstract: A neon sign transformer for operating a neon tube from a mains frequency alternating current comprising: a filter for filtering electro-magnetic interference from said alternating current; a first rectifier for rectifying said filtered alternating current so as to produce a low level alternating current; electrical circuit driver for generating a high frequency low level alternating current; an electrical power circuitry for generating a high frequency high level alternating current then rectified to provide said high level direct current for energizing said neon tubes.

Abstract: A control circuit and method for regulating the current flow through a series connected inductor and transistor. The circuit comprises an operational amplifier for receiving a first voltage proportional to the current flow, for receiving a variable second voltage, and for providing a control current to the transistor which keeps the transistor out of its saturation region.

Abstract: A negative glow discharge lamp device has a discharge container enclosing at least a rare gas, a hot cathode disposed in the discharge container and coated with a thermion radiation matter, and an anode located in a negative glow domain formed between the anode and the hot cathode in the discharge container, a power conversion circuit for driving the lamp device includes a rectifier directly connected at its d.c. output terminals to the hot cathode and the anode respectively for supplying d.c. electric power to the discharge container, and a capacitor ballast connected between a power supply terminal of an a.c. power source and an a.c. input terminal of the rectifier for controlling discharge current in the discharge container.

Abstract: A circuit arrangement suitable for operating a high-pressure discharge lamp (80) in conjunction with a controlled current limiter (6) by means of a control signal which is at least composed of the sum of a lamp-voltage-dependent signal part and a lamp-current-dependent signal part. The invention, the absolute value of the lamp-current-dependent signal part is chosen to be smaller than the absolute value of the lamp-voltage-dependent signal part. The circuit arrangement provides a rapid control, which keeps the lamp voltage substantially constant.

Abstract: A method of and apparatus for supplying high frequency alternating current to a fluorescence lamp. For eliminating a so-called striation phenomenon, a direct current component is induced in the high frequency alternating current passing through a lamp (8). The circuit means inducing said direct current component comprise a capacitor (3), connected in series with the lamp and having a diode (4) or the like connected in parallel therewith.

Abstract: A lamp ballast configuration in which input power is conducted by one circuit board to the switching devices of a half bridge circuit whose output is conducted on a second circuit board with the two circuit boards mounted parallel and spaced apart disposes the device package which extends between the two circuit boards in an exposed position for direct contact to a heat sink. Drive transformers for the switching devices are preferably mounted between the circuit boards and shielded on four of their six sides by a combination of ground planes on the circuit boards and wide, flat ground conductors connecting the ground planes of the two circuit boards. A compact, high efficiency (>91%) RF system is obtained which is suitable for excitation of an electrodeless, high-intensity-discharge lamp.

Abstract: A magnetic-type ballast powers two series-connected fluorescent lamps from a 277 Volt power line. Except when the lamps are loading the ballast, an electronic control circuit provides an intermittently interrupted short circuit across the two lamps: providing for socket voltages high enough to permit lamp ignition for a period of about 25 milli-seconds every two seconds or so, but keeping the average socket voltages low enough to satisfy safety requirements.When initially connecting power to the lamp-ballast combination, the control circuit enters its short circuit state and remains there for two seconds. Then, after two seconds, the control circuit switches into an open circuit, thereby permitting the voltage across the lamps to become high enough to cause lamp starting within a few milli-seconds. If the lamps fail to start, the electronic circuit reverts back to a short circuit within 25 milli-seconds.

Abstract: At the lumen output levels of most ordinary household incandescent lamps, incandescent filaments designed for and operated at about 24 Volt RMS provide substantially higher luminous efficacy than filaments designed for and operated at 120 Volt RMS.A frequency converter, which is adapted to be plugged into and held by an ordinary household electric receptacle, coverts the 120 Volt/60 Hz received from the power line to an output of 120 Volt/30 kHz and provides this output at a receptacle adapted to receive and hold an ordinary power plug.The power plug of an ordinary table lamp is plugged into this frequency converter, thereby providing 120 Volt/30 kHz to its lamp socket instead of the normal 120 Volt/60 Hz.

Abstract: The assembly comprises a light-emitting diode (28) and associated circuit components (38, R1-R4) mounted on a printed circuit board (26) all mounted within a housing (10) formed with securement means such as a screw thread (14) for mounting the assembly in a panel (18) with the led (28) visible from the opposite side of the panel. The circuit components form means for converting a mains voltage at input leads (30) to a low voltage for driving the led, preferably in the form of an i.c. rectifier bridge (38) and a plurality of volgage-dropping resistors (R1-R4).

Abstract: An emergency lighting system provided with a U-shaped fluorescent tube having power supplied by a square wave oscillator connected to a relatively small sized battery. A battery charger is employed to charge the battery when the standard AC source is connected to the network. An electronic switching circuit is included which will switch the oscillator on when a network failure is sensed and will switch if off when the network appears to be operating properly. The switching circuit also ensure that the battery does not discharge below a particular voltage level.

Abstract: A power supply for intermittently energized loads, particularly gas discharge tubes employed as high intensity lights, has a pair of capacitances which are charged to a high voltage level to provide primary and secondary sources of anode voltage for the load. A coupling circuit impedes the discharge of the secondary anode voltage source capacitance when the primary anode voltage source capacitance is discharged through the load whereby a high voltage is present at the load, i.e., a discharge tube anode, immediately subsequent to the tube being extinguished thus reducing the time between successive firings of the tube. The current available for recharging the primary anode voltage source capacitance may also be increased during the time periods when the tube is being rapidly and repetitively fired.

Abstract: The invention relates to an electronic converter for supplying a constant amplitude output voltage while taking from the main supply only a sinusoidal current in phase with the voltage. This device is constituted by an auto-oscillator comprising transistors 7a and 7b for which the duty cycle is automatically regulated, a first inductance 10 constituting an oscillator circuit to which the output energy is evacuated, and second inductance taking off part of the high frequency energy produced to reapply it, after rectification, in series with the mains voltage rectified by the bridge 13, so that the voltage between the common polarized terminals of the auto-oscillator becomes continuous and held at a potential at least equal to the peak mains voltage, which translates into a continuous output voltage envelope. This device is applicable to the production of electronic transformers, power supplies, electronic ballasts, etc., without necessarily requiring electrolytic smoothing capacitors.

Abstract: In a power-line-operated electronic ballast for a gas discharge lamp, an inverter converts a DC supply voltage to a high frequency current-limited operating voltage for a fluorescent lamp. The DC voltage is obtained, at least in part, by forward inductive-discharge conversion of full-wave-rectified unfiltered power line voltage; which forward conversion is accomplished by high frequency switching of an energy-storing inductor; the switching being done by the very same inverter that provides the high frequency lamp operating voltage. As an overall result, power is drawn from the power line with a power factor higher than 98% and with a total harmonic distortion under 10%.

Abstract: A circuit arrangement for starting and operating gas discharge lamps with current of higher frequency comprises an electronic ballast unit connected to a direct voltage input source (2). An electronic switching element (3), which is controlled by a control device (8), is connected in series with an inductive element (4), and the discharge lamp (5). The lamp current flows through the inductive element from which a voltage is derived which is supplied to the control device as a supply direct voltage supply via a rectifier (14) and a smoothing capacitor (16). A first connection terminal of the smoothing capacitor is connected through a first ohmic resistor (18) to a first terminal of the direct voltage input source and a second connection of the capacitor is connected through the lamp (5) to a second terminal of the direct voltage input source.

Abstract: In a power-line-operated electronic ballast, an inverter converts a DC voltage to a high frequency current-limited operating voltage for a fluorescent lamp. The DC voltage is obtained, at least in part, by forward conversion of full-wave-rectified unfiltered power line voltage; which forward conversion is accomplished by high frequency switching of an energy-storing inductor, the switching being done by the very same inverter that provides the high frequency lamp operating voltage. As an overall result, power is drawn from the power line with a power factor higher than 98% and with a total harmonic distortion well under 20%.

Abstract: Disclosed herein is an improved light bulb life extender device made in a small disc-like form and designed to be removably insertable into an Edison-type light bulb socket. The inventive device is operative to place in series with a source of electrical power a silicon bilateral voltage triggered switch specifically designed to allow a voltage output of a predetermined percentage of the voltage inputted thereto. Through this reduction in voltage, the associated light bulb will burn slightly less brightly but with significantly extended life span.

Abstract: An radiant energy transmitter that includes a d.c. to d.c. converter, a d.c. energy storage circuit portion, a triggered radiant energy signaling device, a trigger pulse circuit to initiate operation of the signaling device and an operator adjustable trigger pulse timer circuit portion supplying signals to the trigger pulse circuit at a repetition rate selected by an operator with each signal causing the trigger pulse circuit to provide a trigger pulse to initiate an operation of the signaling device.

Abstract: An economical power-reducing circuit for either a fluorescent lighting fixture or for a high-intensity, low-voltage incandescent lamp has an electrolytic capacitor and a diode connected in parallel with the capacitor. When used in a fluorescent lamp fixture, the circuit reduces power consumed by the fixture, both when used as a lamp substitute or as an attachment that does not eliminate a lamp. When used with a high-intensity, low-voltage incandescent lamp, the power-reducing circuit eliminates a transformer, thus saving both cost and weight. It also should provide a power saving at no reduction in brightness, and should prolong the life of in the incandescent lamp.

Abstract: A full-bridge inverter ballast for a fluorescent lamp comprises two pairs of switching transistors and is conditionally operable to self-oscillate in either of two modes: a first mode wherein one of the two pairs of switching transistors self-oscillates in manner of a half-bridge inverter and powers the thermionic cathodes of the fluorescent lamp, and a second mode wherein both pairs of transistors self-oscillate in manner of a full-bridge inverter and then powers the main gas discharge of the fluorescent lamp. The first mode gets initiated immediately upon applying power to the ballast, but the second mode does not get initiated until about 1.5 seconds after the initiation of the first mode. The way, the cathodes will have become fully thermionic prior to applying main power to the fluorescent lamp.

Abstract: A light emitting diode lamp that operates directly from an AC input. The lamp has an even number of light emitting diodes that are disposed on a cylindrical cluster plate. The diodes are separated into two halves that are conductable in opposite electrical directions. The two halves of diodes are connected at two terminals. The diodes are arranged in a circular configuration near the edge of the circular cluster plate. Leads are connected to the terminals. The leads extend toward the center of the circular configuration and extend through the cluster plate. A modifying resistor is connected between one lead and an end terminal of a lamp housing. The other lead is connected to a base terminal of the lamp housing.

Abstract: A DC-AC converter for igniting and supplying a gas discharge lamp (1). The converter has two input terminals (C, D) to be connected to a DC voltage source. The input terminals are interconnected by means of a series arrangement that includes a load circuit comprising at least the lamp (1) and an induction coil (5), and a first semiconductor switching element (6) including a freewheel diode. The load circuit is bridged by a circuit including a second semiconductor switching element (7) with a freewheel diode. The semiconductor switching elements (6, 7) are provided with control circuits for rendering said switching elements alternately conducting. The control circuit (9) of switching element (7) has a voltage measuring point which is connected via a rectifier element (10) to the control circuit (8) of the first switching element.

Abstract: The present invention relates to a method and apparatus for driving discharged lamps and which is adapted to maximize the luminous efficiency of a discharged lamp and its associated electronic driving apparatus. This is accomplished through the power sourcing characteristics of the driver, by causing the required power to dissipated while maintaining the power factor in the lamp as near unity as possible with the real components available for the implementation of the apparatus.

Abstract: A fail safe feature for long life reduced voltage lamps including diodes id disclosed. As known, a low wattage lamp may designed for longer life by using a lower root mean square design voltage. The root means square voltage of the alternating source current may be lowered by including a rectifying element, and a fuse may be included in series with the lamp to safely interrupt the circuit. By further including a one-way shunt oriented oppositely to the rectifier, in parallel with the lamp, and intermediate the rectifier and fuse, on failure of rectifier, unrectified current blows the fuse. If the rectifying diode fails, substantially all of the current is shunted to the fuse during the failed half of the current cycle, thereby blowing the fuse, and safely failing the lamp.

Abstract: The longevity of an incandescent electric lamp and its efficiency of light production are increased by utilizing a rectifier externally attached to the base of the lamp, and by employing within the glass envelope a gas mixture comprising 75% to 85% krypton and 15% to 25% nitrogen. By virtue of the placement, manner of attachment, and configuration of the rectifier, it dissipates heat to the ambient air and thereby operates at a reduced temperature which increases its performance and longevity.

Abstract: A high frequency dimming ballast dims to about 1 percent of rated output in a repeatable way so that parallel connected dimming ballasts will all produce the same light illumination when dimmed to a very low percentage of their rated light output. A first current sensor is connected in series with a semiconductor power switching device which is coupled to and controls power to the ballast. A second current sensor is connected directly to the lamp circuit to detect actual lamp current, particularly at low illumination conditions, for example at less than 10 percent of the rated light output. Lamp control under low illumination conditions is derived from the lamp current sensor and overrides control by the sensor in series with the transistor switch means.

Abstract: A voltage reduction unit for reducing the voltage supplied to a lighting element to a prescribed value and for maintaining the prescribed voltage across the lighting element independently of the current flowing through it. A lighting element is connected in series with a current switch, and the current switch is controlled by a voltage/current control unit which monitors the lighting element for changes and voltage and current characteristics. The voltage/current control unit comprises a differentiator circuit for detecting a slope of an AC voltage waveform and a comparator circuit for detecting a prescribed voltage on the waveform. The voltage/current control unit allows current to flow through the lighting element when both a first prescribed voltage and a prescribed voltage slope of the voltage waveform is detected, and it inhibits current flow through the lighting element when a second prescribed voltage is detected.

Abstract: A circuit arrangement for operating at least one gas discharge lamp (5) with a periodically varying lamp current and adapted for connection to an alternating voltage source with a period N. The circuit is provided with a controlled semiconductor switch (3) and a control circuit for switching the controlled semiconductor switch with a switching period S in dependence upon a comparison between an actual signal proportional to the lamp current and a nominal signal derived from a voltage across the switching transistor (3).

Abstract: A system for driving a neon tube to form luminous bubbles and controlling the motion thereof in which a modulatable high AC voltage source is connected to control a pair of electronic switches in the primary circuit of a high voltage transformer which is connected to electrodes of said neon tube in such a way as to produce the luminous bubbles, which can be stationary or moved at varying speeds and direction by control of width and/or frequency of control pulses applied to the electronic switches. A memory stores predetermined patterns of the direction and speed of said luminous bubbles and microprocessor means for controlling said modulatable AC voltage in accordance with said predetermined pattern by said memory means to cause said luminous bubbles to move in said predetermined patterns of direction and speed. The memory may include a plurality of predetermined patterns stored, and selector for selecting one of said patterns and driving the neon tube therewith.

Abstract: This invention is a circuit for controlling the power received by a load. The operation of this circuit is based on variations of voltage amplitude rather than phase as is the case with other circuits utilizing the phase control principle. A pair of terminals couple an AC service voltage source to a load and to a distributor switch by which an operator can arrange for the load to receive power directly from the AC service voltage source, or through a transformer and a gated switch, or through a diode. The operation, by way of the transformer and the gated switch or by way of the diode, provides not only "soft-start" and protection from power line transients (voltage spikes) to the load but also prevents it from emitting acoustical noise.

Abstract: A fluorescent illuminator including a fluorescent lamp, a lamp housing, and a lamp power supply with a variable current output with a relatively fixed frequency at least an order of magnitude greater than line frequency and a non-integral multiple thereof. There are means for connecting the power supply to the lamp and also means for varying the current output of the power supply between a first, lowest level and a second, highest level to change the light intensity of the fluorescent lamp.

Abstract: An apparatus for starting and operating a discharge lamp includes an inverter circuit. The inverter circuit comprises a parallel resonance circuit including an oscillation coil and capacitor, and which is connected to the discharge lamp, via a current-limiting coil, a switching transistor for triggering the parallel resonance circuit, and a feedback circuit connected to the switching transistor, for allowing a feedback signal for driving the switching transistor to be supplied to the base of the switching transistor, the feedback circuit being magnetically coupled to the current-limiting coil.

Abstract: A circuit arrangement for operating a high-pressure gas discharge lamp (3) with a pulsatory direct current produced from an alternating voltage supply (A, B) via a full-wave rectifier (1). The output of the full-wave rectifier is shunted by a series arrangement of a diode (4) and a capacitor (5). The capacitor (5) has a value of 10 nF to 1 .mu.F and a resistor (6), which is high-ohmic with respect to a current limiter (2) in series with the lamp (3), is connected in a current circuit between the end of the capacitor facing the diode and the lamp (3). As a result, a low re-ignition voltage is attained during the head-up phase of the lamp.

Abstract: A load side phase control circuit is used in conjunction with a conventional fluorescent light ballast (step-up autotransformer) and an isolation transformer to achieve fluorescent lamp brightness control. A resistor and capacitor connected in series shunt the phase control circuit to maintain low level illumination even when the phase control circuit is nonconducting and also provide a transient suppression when the phase control circuit switches to a conducting state. The circuit is especially suited to printed circuit board preassembly and subsequent connection to the lamp and ballast by a one step crimping operation. The resulting fluorescent lamp system--of the rapid start type--is well suited for use as a task light where the lamp is mounted relatively close to an underlying work area and receives power from a conventional outlet.

Abstract: To suppress introduction of harmonics into the power supply network of a high-frequency operated fluorescent lamp, an input capacitor (C2) connected across a direct current supply (P1, P2) for a transistor push-pull high-frequency circuit--operating at between 25-50 kHz--has a pair of serially connected diodes (D4, D5) connected thereto. The junction point (M2) of the diodes is connected via a coupling capacity (C7) to a common junction (M1) of the push-pull connected transistors (T1, T2). The power line circuit has a line choke (L2, L2') connected, either in advance or behind a rectifier (G1) supplying direct current to the transistor push-pull circuit. The circuit effectively suppresses harmonics, particularly the third harmonic, without introducing additional losses in the circuit, especially if a further capacitor (C8) is connected in the resonance circuit of the fluorescent lamp and to the diode junction (M2) between the two diodes (D4, D5).

Abstract: An electronic ballast or energizing circuit for a fluorescent lamp is disclosed. A rectified supply voltage is applied through an electronic switch to a fluorescent lamp through a current sensing resistor. A switching regulator produces a pulse width modulated pulse train which is applied to the electronic switch for supplying a pulsed voltage across a smoothing filter to the fluorescent lamp. The pulse width output of the switching regulator is modulated in accordance with the voltage across the sensing resistor for maintaining the current drawn by the lamp at a substantially constant value.

Abstract: A luminaire using a tungsten-halogen lamp, includes a circuit for supplying the lamp with a boosted D.C. operating voltage. The circuit includes a full-wave rectifying circuit for receiving a standard A.C. mains supply voltage, and a low pass filter connected to the output of the rectifier. The value of the time constant of the filter is chosen to produce at the rectifier output, an average D.C. voltage of about between 135 and 146 volts, preferably about 140 volts.

Abstract: A power supply for a metal halide discharge lamp includes a circuit for applying a high voltage starting pulse to the arc tube of the lamp to initiate the discharge, a glow transition current to provide power transitioning the arc tube from its glow to its run mode, and a run power supply circuit to provide continuous controlled d-c current to the arc tube.

Abstract: A circuit arrangement for A.C. operation of gas discharge lamps comprises a full-wave rectifier (1) connected to an alternating voltage source. The direct voltage is supplied to a combinatorial circuit part (3 to 8) in the form of a direct voltage converter, to which is connected a bridge circuit (9) which comprises four thyristors. The transverse branch of the bridge circuit includes the lamp (5). The full-wave rectifier (1) is followed by a smoothing capacitor (2) and an electronic switching element (14) is connected parallel to the bridge circuit (9). The switching element is switched to the conducting state in the vicinity of the zero passages of the input alternating voltage. As a result shortcircuits in the bridge circuit are avoided.

Abstract: According to the present invention, a portion of an applied commercial AC supply (60 Hz) is rectified, filtered and a controllable oscillator in a pulse width modulator chip serves as a signal generator which has both duty cycle and frequency control adjustments. An output signal is coupled via an impedance matching circuit to the input primary winding of a signal transformer having a pair of secondary windings which drive a pair of tandem connected electronic switches which, in turn, are connected across a second DC supply which has a high direct current voltage derived from the input AC line voltage (110-120 V AC 60 Hz).

Abstract: A load is provided, at all times when in operation, with a D.C. voltage having at least a minimum holding magnitude by: providing a source voltage having a peak magnitude greater than the holding magnitude; connecting the source voltage to the load only while the source voltage magnitude is greater than a preselected magnitude; charging from the peak source voltage magnitude an energy storage element while the load is connnected to the source voltage; energizing the load from the charged energy storage element whenever the source voltage magnitude is less than the preselected magnitude; increasing the effective impedance of the load whenever the load is energized by the storage element; and selecting the energy storage element to provide at least the holding voltage to the load during each time interval when the energy storage element is connected to the load.

Abstract: An adaptation circuit (3) for operating a high-pressure discharge lamp (1) via a controlled semiconductor switch (4) in series with the lamp. The control circuit for the switch (4) to comprise a voltage division circuit (5,6). The voltage division circuit is connected in parallel with the switch when the lamp is connected to the circuit output terminals (E,F) and one branch of the voltage division circuit comprises a parallel-combination of a capacitor (57) and a resistor (56). Thus, the variation of the voltage across the lamp influences the control of the semiconductor switch so that it is possible to stabilize, for the major part, the power dissipated by the lamp against, variation in the supply voltage and against lamp voltage variations during the life of the lamp.

Abstract: A conventional pilot lamp which is used in a power plant, substation, or other types of plants, each has its own large and heavy weight transformer below the lamp case. In order to obtain a pilot lamp having the same capacity as the conventional pilot lamp even if the transformer is taken away from the lamp case, the pilot lamp of this invention comprises a lamp, a lamp holder, a heat radiating plate fixed within the lamp holder, an extremely small-sized IC type AC-DC constant voltage regulator connected to the input terminal fixed to the lamp holder, and an output terminal connected to the lamp. Thus, the arrangement contemplated produces a pilot lamp having the same capacity as a conventional pilot lamp, without the large and heavy weight of the transformer unit below the lamp case.

Abstract: A power supply is provided for an arc discharge lamp (38) which includes a relatively low voltage high current power supply section and a high voltage starter circuit (10). The low voltage section includes a transformer (15), rectifier (24), variable resistor (26) and a bank of capacitors (28), while the starter circuit (10) comprises a plurality of diodes (D1 to D12) and capacitors (C1 to C12) connected as a Cockcroft-Walton multiplier. The starting circuit is effectively bypassed when the lamp arc is established and serves to automatically provide a high starting voltage to re-strike the lamp arc if the arc is extinguished by a power interruption.

Abstract: A high frequency ballast circuit powered by a dc input voltage source for starting and operating a gas discharge lamp load, comprising: a means for providing drive signals, each the drive signal having a first and second state, a series switch having a conduction channel having a first and second terminal, the series switch having a control terminal responsive to the drive signals, the conduction channel is on (conductive) in responsive to the interval characterized by the first state of the drive signal and off (non-conductive) in response to a drive signal having a second state, and an inductor. A clamp diode is included. The inductor is coupled to the clamp diode cathode and to the series switch. A ballast reactance is included with a a power oscillator circuit, the power oscillator circuit has a transformer having, a primary winding having a first, a second and a center-tap terminal, a drive winding having a first and a second and a center-tap terminal, and an output winding.

Abstract: With the AC voltage output from an inverter series-driving a high-Q parallel-loaded resonant L-C circuit, and with the parallel-connected load being of a type that needs to be conditioned before it will absorb power (as would be the case with loads such as magnetrons or fluorescent lamps), the inverter and/or the L-C circuit may be destructively overloaded during the time it takes for the load to become conditioned.In a power-line-operated inverter-type power supply with such a high-Q parallel-loaded resonant L-C circuit series-connected across its output, subject invention provides for means to prevent such destructive overload. In this power supply, the unfiltered pulsed DC output of a full-wave power-line-supplied rectifier is applied to a pair of inverters: an auxiliary inverter for pre-conditioning the load, and a main inverter for powering the load.