Abstract: A terminal apparatus includes a light modulation unit to perform an automatic light modulation of a touch panel, an illuminance sensor, a proximity sensor, an illuminance determination unit to determine whether or not an illuminance detected by the illuminance sensor varies, and an operation determination unit to determine whether or not an operation of the touch panel occurs near the illuminance sensor, wherein the light modulation unit suspends the automatic light modulation when the operation of the touch panel occurs before a first time elapses after the detected illuminance decreases, and the light modulation unit suspends the automatic light modulation when the operation determination unit determines that the operation of the touch panel does not occur before the first time elapses after that the detected illuminance decreases and then the proximity sensor detects an object before a second time elapses.

Abstract: A light source driving apparatus, a display apparatus and a driving method thereof are disclosed. The light source driving apparatus includes a tapped-inductor boost converter (TIBC) circuit, the TIBC circuit including: a switching unit configured to be turned on and off in accordance with a preset cycle; a tapped inductor configured to transfer a current from a primary side to a secondary side as the switching unit is turned on; and a snubber configured to include a clamp capacitor and clamp diode configured to clamp a voltage of the switching unit, a resonance capacitor configured to perform a resonance as being charged and discharged corresponding to a switching cycle of the switching unit, and first and second resonance diodes configured to charge and discharge the resonance capacitor. Thus, the TIBC circuit provided with the lossless snubber can prevent the voltage stress from increasing during the resonance since the voltage of the switching unit is clamped.

Abstract: The present invention relates to a controlling circuit and controlling method for an LED driver implemented as a flyback topology. The controlling circuit may be at a primary side of a transformer of the LED driver, and include a sampling circuit, an on time sensing circuit of an output diode, a regulating signal generator, and a PWM controller. The sampling circuit may generate a sampling signal indicating output current by sampling at the primary transformer side. The on time sensing circuit can detect an on time of the output diode. The regulating signal generator can generate a regulating signal by regulating the sampling signal, a voltage reference, and the on time of the output diode. The PWM controller may generate a controlling signal to control operation of a switching device of the LED driver to maintain a substantially constant output current in accordance with the regulating signal.

Abstract: A wireless power supply system for lighting includes: a power transmission unit including a power transmission coil; and a power reception unit including a power reception coil. The power transmission coil generates an AC magnetic field in response to a supplied AC power. The power reception coil receives an electric power from the power transmission unit through an electromagnetic induction due to the AC magnetic field generated by the power transmission coil. The power reception unit further includes a power circuit and a receive-side control section. The power circuit receives an output power from the power reception coil and to perform Buck-Boost operation so as to output a predetermined electric power to a lighting load. The receive-side control section controls the Buck-Boost operation of the power circuit. The power circuit is configured to be capable of boosting and stepping-down of the output power from said power reception coil.

Abstract: In various embodiments, a two-switch flyback power supply may include a transformer having a primary winding and a secondary winding to feed a load; a pair of electronic switches alternatively switchable on and off to connect the primary winding of said transformer to an input line to feed said primary winding of said transformer, wherein at least one of said electronic switches is an electronic switch having a control electrode floating with respect to ground; a capacitive voltage divider arranged between said input line and the ground of the device, with the dividing point of said capacitive voltage divider connected to an intermediate point of said primary winding of said transformer; and an auxiliary secondary winding in said transformer, said auxiliary secondary winding feeding the control electrode of said at least one of said electronic switches.

Abstract: An LED backlight driving circuit including a boost circuit and a transformer current balance circuit is provided. The boost circuit provides a total current for n LED strings, and the transformer current balance circuit is coupled to the LED strings and includes n?1 transformers. A first LED current-balance-circuit (CBC) includes a switching-transistor connected to a secondary-winding of a first-transformer, and an nth LED CBC includes a switching-transistor connected to a primary-winding of an (n?1)th transformer. An ith (1<i<n, n>2) LED CBC includes a switching-transistor sequentially connected to a primary-winding of an (i?1)th transformer and a secondary-winding of an ith transformer. The passive-transformers are applied in the LED driving circuit to implement current balance/equalization, such that the LED backlight driving circuit is suitable for a system with any odd or even number (greater than 1) of the LED strings connected in parallel, so as to reduce the cost of the system.

Abstract: A control circuit of a light-emitting element comprises a rectifying unit (30), a switching element (38), a transformer (48) having a first winding (L1) which generates a magnetic field using a current controlled by switching of the switching element (38), a second winding (L2) which is magnetically coupled to the first winding (L1) and which generates a current flowing to an LED (102), and a third winding (L3) which is magnetically coupled to the first winding (L1) and which generates a voltage (Sfbk), and an averaging capacitor (32) which averages a voltage derived by superposing a voltage (Srec) rectified by the rectifying unit (30) and the voltage (Sfbk), and a voltage averaged by the averaging capacitor (32) is applied to the first winding (L1), so that light is emitted from the LED (102).

Abstract: A method for controlling a high-frequency transformer by which the acoustic transformer noises occurring during intermittent operation (burst operation) are reduced. This is achieved according to the invention by halving a length of the first and the last pulse of an AC voltage pulse train or the first and the last half-wave in the ON interval (Tn). This goes to avoid magnetizing peaks in the core that cause a major part of the background noise.

Abstract: An HID lamp ignitor for a lamp including a transformer (92) having a primary winding (94) inductively coupled to a secondary winding (96) operably connected to a lamp output (98); a first switch circuit (100) operably connected between DC voltage (102) and a junction point (104), the first switch circuit (100) being responsive to a first switch signal (112); a second switch circuit (120) operably connected between the junction point (104) and common (124), the second switch circuit (120) being responsive to a second switch signal (132); and an LC tank circuit (140) having the primary winding (94) operably connected in series with a capacitor (142), the LC tank circuit (140) being operably connected between the junction point (104) and the common (124). The first switch signal (112) alternates with the second switch signal (132) to close the first switch circuit (100) and the second switch circuit (120).

Abstract: A circuit (200) for powering a high intensity discharge lamp (10) comprises first and second input terminals (202,204), first and second output terminal (206,208), first and second inverter switches (SW1,SW2), a transformer (240), first and second buck capacitors (CBUCK1,CBUCK2), first and second low-side capacitors (CLOWSIDE1,CLOWSIDE2), an ignitor (216), and a diode subcircuit (250,260). Transformer (240) includes a primary winding (242) and a secondary winding (244). During operation of circuit 200, primary winding (242) functions as a buck inductor, while secondary winding (244) operates in conjunction with diode subcircuit (250,260) to provide enhanced low frequency open circuit voltage (OCV) during the lamp starting phase and during steady-state powering of the lamp (10). Circuit (200) also allows for a lamp current having a non-zero average value. Circuit (200) is realizable with first and second low-side capacitors (CLOWSIDE1,CLOWSIDE2) having a relatively low capacitance value.

Abstract: An incremental distributed driver divides power delivered to multiple lamps into two power delivery stages. The first power delivery stage operates in voltage-mode to provide a partial operating voltage to the lamps. The second power delivery stage operates in current-mode to regulate current levels for each of the lamps and to provide additional operating voltages for the respective lamps. Each of the power delivery stages includes a polarity-switching network and a common set of driving signals from a controller can be used to drive the polarity-switching networks of both power delivery stages. The first power delivery stage delivers a majority of the power to the lamps and the second power delivery stage facilitates control of individual lamps while providing the remaining power to the lamps.

Abstract: A device for operating a plurality of discharge lamps (71, 72) is to be fashioned cost effectively. Two lamps (71, 72) are therefore operated in a single load circuit. In the preheating phase, the incandescent filaments (711, 712, 721, 722) are supplied with preheating current either directly or via a transformer (Ls, Lp). The preheating current is controlled via a temperature-dependent resistor (PTC) in such a way that the continuous heating current is greatly reduced over all the filaments during the operation of the lamp.

Abstract: The electronic ballast may be fitted to a wide variety of third party lamps and is usually controlled to allow for a variety of light settings. A simple ballast circuit is provided in which both the ignition and regulation functions are carried out by the same inductor. This removes a switching stage resulting in better efficiency. The ignition energy of the lamp is progressively built up which helps reduce Radio Frequency Interference and reduces Electrical Magnetic Interference and reduces wear on the lamp components.

Abstract: The present invention relates to a plasma generator to apply cold plasma in the fields of medicine, biology, ecological recovery, activation, purification, special processing of gases, liquids and solid substances as well as other areas of technology and science. A plasma generator of the invention comprises: a power source; an electronic oscillator constructed on an amplifying (control) element which is connected to a low voltage input section; a resonance transformer having a low voltage input section and a high voltage output section; and, one pin of the high voltage output section of the resonance transformer which is connected to a discharge electrode. The present invention provides a universal plasma generator with decreased mass and dimensions which provides unipolar plasma for plasma therapy and activation of substantial media by virtue of the field.

Abstract: A circuit for driving gas discharge lamps has a bandpass filter coupled between the output of the inverter and the inverter control. The bandpass filter provides protection against the diode operation of the gas discharge lamps. The bandpass filter is composed of a capacitor and the permeance inductance of a transformer.

Abstract: An improved self-regulating, no load protected electronic ballast system (10) is coupled to a power source (12) for actuating at least one gas discharge tube (b 66) with a regulated current and limited voltage to maintain the gas discharge tube (66) input and output power at a predetermined value. The improved ballast system (10) includes a filter circuit (11) coupled through a rectification circuit (16) to the power source (12) to provide a filtered output (28). The output line (28) is coupled to a first toroidal transformer winding (58) of self-regulating circuit (17) for monitoring the regulated current coupled to induction circuit (15). The induction circuit (15) includes a primary winding (42) tapped to provide an autotransformer configuration for establishing the magnitude of the regulated current.

Abstract: A parallel RC network sensitive to the impedance of a gas discharge device is provided in the electronic ballast of this device along with a series connected inductive coil. As the impedance through the device changes, the oscillator frequency of the ballast would change accordingly and the voltage through the coil would change, thereby changing the impedance in such a manner as to insure that the voltage through the gas discharge device remains unchanged. The ballast would include a switch-mode, push-pull oscillator including a pair of emitter-resistors and a pair of fast diodes.

Abstract: A matching circuit arrangement for operating a high-pressure discharge lamp. The circuit arrangement is provided with first and second input terminals for connection to a supply source, each of which is connected to a respective first and second output terminal. The output terminals are intended for connection of the high-pressure discharge lamp. A first controlled semiconductor switching element A having a thyristor characteristic is included in a connection between the second input terminal and the respective second output terminal. A control electrode of the switching element A is connected to a main electrode BE2 of a second controlled semiconductor switching element B having a thyristor characteristics. The main electrode AE2 of the first switching element is connected together with the main electrode BE1 of the second switching element to the second input terminal. The main electrode AE1 of the first switching element is connected to the second output terminal.

Abstract: A self-regulating, no load protected electronic ballast system (10) is provided which includes a power source (12) for actuating at least one gas discharge tube (66) with a regulated current and limited voltage to maintain the gas discharge tubes (66) input and output power at a predetermined value. The self-regulating, no load protected electronic ballast system (10) includes a filter circuit (11) coupled to the power source (12) with an induction circuit (15) coupled to the filter circuit (11). The induction circuit (15) has a tapped primary winding (42) providing an auto-transformer configuration for establishing the magnitude of the regulated current.

Abstract: Starting and operating apparatus for high intensity discharge lamps includes first and second pairs of terminals formed for connection to an AC source and a discharge lamp respectively, a series connect ballast means and inductor connected to one of said first pair and one of said second pair of terminals a bilateral switch shunted by a capacitor and in series with an AC impedance coupled to the inductor and to the other one of said first and second pair of terminals whereby relatively wide high voltage, high frequency pulse potentials for starting the discharge lamps are provided.

Abstract: A current driven gain controlled electronic ballast system (100) is provided having a power source (112) for actuating a pair of gas discharge tubes (140 and 140'). The ballast system (100) includes a filter network (111) which is connected to the power source (112) for establishing a substantially constant voltage signal and suppressing harmonic frequencies generated by the electronic ballast system (100). An induction circuit (115) is coupled to the filter network (111) for generating a voltage across the gas discharge tubes (140 and 140') responsive to the driving current. The induction circuit (115) includes an automatic gain control network (117) to maintain the driving current at a predetermined value and includes a trigger network (117) for generating a switching signal.

Abstract: DC operated power supplies for electroluminescent lamps are self-inhibited from further oscillations and thus are current limited in the event that a failure occurs in an EL lamp which results in the EL lamp being shorted. Single ended and push/pull transformer power supplies are disclosed, and a transformerless solid state power supply is disclosed utilizing a voltage multiplier, and an inhibitor circuit at the output of the voltage multiplier responsive to substantial voltage drop upon the occurrence of a shorting of the EL lamp, to inhibit further oscillations and operations of the circuit.

Abstract: A magnetic ballast circuit for a fluorescent lamp providing improved power factor, reduced harmonic content and increased efficiency. A ballast circuit with three inductances connected to a junction, preferably with the first and second inductances comprising a tapped autotransformer, with the third inductance connected between a line terminal and the tap, with the first inductance connected in series with a capacitance to the other line terminal, and with the second inductance connected to the load. The first inductance may be provided totally as part of the autotransformer, or may be supplemented with a second inductance in series. In an alternative embodiment, separate inductances may be utilized.

Abstract: The above and other objects, advantages and capabilities are achieved in one aspect of the invention by an output circuit for an electronic ballast system. The circuit includes N sets of output connections for accepting N lamps. The lamps are driven by an output autotransformer coupled to the lamps through a feedback winding that is used to apply a feedback signal to an inverter drive circuit. Capacitive impedances are coupled across the lamps so that the capacitances, the lamp filaments, the feedback winding, and the output transformer form a circuit loop. The capacitances are chosen to have an impedance, at the inverter operating frequency, less than the pre-ignition impedance of the lamps and greater than the post-ignition impedance.

Abstract: A solid state power supply and light emission controller for a cold cathode luminescent tube which converts alternating current line voltage, or direct current voltage, into a variable repetition rate pulse alternating current voltage for energizing the tube and for controlling the light emission of the tube. The power supply provides for essentially constant light emission from the tube in the presence of variations in the internal impedance of the tube, variations in ambient temperature, and variations in line voltage. The power supply finds use, for example, with cold cathode luminescent tubes such as neon tubes, and the like.

Abstract: A frequency stabilized automatic gain controlled ballast system (10) which is coupled to a power source (12) in order to operate at least one of a pair of gas discharge tubes (40 and 40'). Each of the gas discharge tubes (40, 40') include respective filaments (42, 44 and 42', 44'). A frequency control circuit (11) is coupled to the power source (12) and includes a frequency control transformer (43) and a frequency control capacitor (50) for establishing a constant oscillation signal at a predetermined frequency. A switching network (13) is connected to the frequency control circuit (11) for establishing a pulsating current responsive to the constant oscillation signal of predetermined frequency. Induction circuitry (15) is coupled to the switching network (13) and the frequency control circuit (11) and includes an inverter transformer (78) as well as coupling capacitors (86 and 88) for generating a voltage across the gas discharge tubes (40 and 40').

Abstract: An electronic ballast system (200) which is coupled to a power source (204) in order to actuate at least one of a pair of gas discharge tubes (202 and 202'). Each of the gas discharge tubes (202, 202') include respective first and second filaments (206, 208 and 206', 208'). The system (200) includes a first transformer (238) which is coupled to the power source (204) and the first transformer (238) includes a primary winding (240) and a secondary winding (242) for establishing an oscillation signal. A first and second transistor network (252 and 254) are feedback coupled to the first transformer (238) for switching a current signal responsive to the oscillation signal. Additionally, a first and second inverter transformers (210 and 212) are provided with each of the inverter transformers (210 and 212) having in tapped windings (288 and 290) respectively, for establishing an induced voltage signal responsive to the current signal.

Abstract: A DC-DC converter circuit particularly for use in a photographic flash light emitting device for producing high DC voltage from a low DC voltage such as a battery. Heretofore, the converter transformer of such a circuit has three coils, i.e. a primary coil to be connected to a low DC source, a secondary coil to produce high voltage and a feedback coil for feeding feedback current to the base of a chopping transistor. The purpose of this invention is to eliminate the need for a feedback coil by feeding current from said high voltage in the secondary coil to the base of a transistor.

Abstract: A high frequency oscillator-inverter ballast-ignition system for a discharge lamp includes a leakage reactance transformer that forms a part of the oscillator-inverter and also couples same to the discharge lamp. An impedance element electrically couples the primary and secondary windings of the transformer in additive phase to provide more reliable lamp ignition over a wider range of voltage and temperature than was heretofore possible. The preheat time period of the lamp cathodes can be better controlled by a proper choice of the transformer heater winding turns.

Abstract: A bifluxer type transformer for use in a static inverter utilizes an E-E or shell-type core. Such configuration is particularly suitable for ballasting hid lamps because it minimizes stray flux which causes eddy current losses in the luminaire metal enclosure. A pair of apertures are provided in the yoke area, one above and the other below the central leg, around which the main winding is wound. Control windings are looped through the apertures and provide feedback from the output to the input of a power transistor as a result of linkage by transverse flux.

Abstract: An impulse generator for use with phosphor energizable lamps, e.g. gaseous discharge lamps and electroluminescent lamps, and which eliminates the need of a conventional ballast and starting mechanism. The impulse generator includes a pair of terminals which are adapted to be connected to a conventional source of alternating electrical current with a diode rectifying bridge for rectifying the electrical current. A solid-state circuit switching element is connected to the rectifier and operates in conjunction with a timing means including a resistive capacitive network. Moreover, the solid-state switching element is connected to a primary coil which is coupled to a secondary coil. The secondary coil includes terminals for connection to the lamp. The circuit is operable to generate pulses in a sequence and at time intervals sufficient to maintain energization of the lamp.

Abstract: A generator for the starting and thereafter maintaining energization and operation of a load which has a relatively high impedance during starting and a substantially lower impedance after starting and during operation thereof. The load may be an ionic conduction lamp including a phosphor excitable lamp in the nature of a fluorescent lamp, or electroluminescent lamp, or vapor lamp. The generator includes a mechanism for generating electrical power with a relatively high voltage and impedance so as to match the relatively high impedance of the load before starting and generization of electrical power of a substantially lower voltage and impedance so as to match the lower impedance of the load during the energizing and operation of the load. The mechanism for generating the electrical power may be an inductive member, such as a coil, and a solid state element, such as a transistor, to develop a voltage over the coil. The coil may be coupled to the lamp through some agent developing a capacitance, e.g.

Abstract: There is disclosed an oscillator circuit for driving a fluorescent lamp, which comprises a power transistor having an emitter electrode connected to one terminal of a D.C. power source and a collector electrode connected to the other terminal of the D.C. power source through a primary winding of a transformer. A first secondary winding of the transformer is connected at its one end to the other terminal of the D.C. power source and at its other end to a base electrode of the transistor through one of a pair of filaments of the fluorescent lamp. A second secondary winding of the transformer is connected at its one end to the one filament of the fluorescent lamp and at its other end to the other filament of the fluorescent lamp to cause discharge in the fluorescent lamp.

Abstract: A fluorescent lamp lighting device comprises a d.c. power source, a transistor, a transformer and a fluorescent lamp. The d.c. power source is connected in series with the primary winding of the transformer between a first electrode and a second electrode of the transistor. The fluorescent lamp has one filament connected to one end of a first secondary winding of the transformer. A second secondary winding of the transformer is connected between the other end of the first secondary winding of the transformer and the junction of the d.c. power source and the primary winding of the transformer. The fluorescent lamp has the other filament connected between the junction of the first secondary winding of the transformer and the second secondary winding and a third electrode of the transistor.

Abstract: Color properties of high pressure sodium vapor discharge lamps are improved by disclosed operating circuit for applying pulsed direct current to the lamp. The circuit comprises a direct current supply circuit, a transistor switch in series with the lamp and the primary of a transformer connected across the supply circuit, a diode in series with the secondary of the transformer connected across the supply circuit, and SCR switch connected across the secondary of the transformer, and a control circuit connected to the switches for applying DC pulses to the lamp at a predetermined repetition rate and duty cycle. The circuit produces pulse waveforms which provide substantial color improvement in the lamp and makes efficient use of the energy supplied from the power source.

Abstract: A power source for operating gas discharge lamps and other loads at high frequency, typically utilizing a 115 volt ac source rectified to provide a dc input in the order of 150 volts, and providing a 20,000 hertz output. An inverter with power supply, oscillator circuit and transformer, with conventional primary, secondary and feedback windings for operating the transistor oscillator. An additional output winding on the transformer with a rectifier and filter providing a supplemental dc supply connected to the main dc supply in parallel or in series to supplement a fluctuating main dc supply and maintain continuous oscillator operation while utilizing small filter capacitance and substantially reducing peak ac line current.