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| Number | Title | Issue Date |
| 7642724 | Light emitting element driving circuit A light emitting element driving circuit, which can achieve accurate/high-speed operation even at low voltage supply voltage, comprises: driving current supply, connected to light emitting element in series between first and second power supplies, to supply driving ... | 01/05/2010 |
| 7439682 | Current driving circuit for inductive loads A circuit for driving the current for inductive loads such as a electron beam deflection coil for an x-ray generator system. The circuit includes two selectable voltage levels which are provided by a high level voltage source and a low level voltage source or, alter... | 10/21/2008 |
| 7368879 | Pendulum resonant converter and method A resonant switching converter comprising a first pair of series connected switches comprising a high side switch and a low side switch coupled across a DC input voltage, there being a first switched node between the switches; a second pair of series connected switc... | 05/06/2008 |
| 7354780 | Semiconductor light emitting devices and methods A method for producing an optical output, including the following steps: providing first and second electrical signals; providing a bipolar light-emitting transistor device that includes collector, base, and emitter regions; providing a collector electrode coupled w... | 04/08/2008 |
| 7286583 | Semiconductor laser devices and methods A method for producing controllable light pulses includes the following steps: providing a heterojunction bipolar transistor structure including collector, base, and emitter regions of semiconductor materials; providing an optical resonant cavity enclosing at least ... | 10/23/2007 |
| 7170235 | Circuit arrangement with a separate resonant igniter for a high-pressure discharge lamp In a bridge circuit for operating a high pressure discharge lamp an additional switching element, a control circuit for driving the additional switching element, a resonant inductor and a resonant capacitor are incorporated. The additional components together form a... | 01/30/2007 |
| 7129649 | Ballast with braking inductance A ballast for at least one lamp at least two switches arranged in series; a control circuit for alternately opening and closing the two switches; a connection for applying a supply voltage to the two switches; a resonant starting circuit coupled on the input side to... | 10/31/2006 |
| 7102295 | Electronic device with illumination circuit and EL device utilizing the same An electronic device having an illumination circuit. The illumination circuit utilizes an AC current of an AC driving device to drive an illumination device such as an electroluminescent lamp and the remaining life of the AC driving device indicated by the brightnes... | 09/05/2006 |
| 7091082 | Semiconductor method and device A method for enhancing operation of a bipolar light-emitting transistor includes the following steps: providing a bipolar light-emitting transistor having emitter, base, and collector regions; providing electrodes for coupling electrical signals with the emitter, ba... | 08/15/2006 |
| 7049756 | Capacitive load driving circuit, capacitive load driving method, and apparatus using the same A capacitive load driving circuit (1) for charging and discharging a capacitive load (11) is provided with a voltage divider (5) for dividing a power supply voltage (VH) into a plurality of different voltages (V1–V9), a plurality... | 05/23/2006 |
| 6900446 | Charged particle beam irradiation equipment and control method thereof A power supply for applying a voltage to a scanning electromagnet for deflecting a charged particle beam has a first power supply unit having no filter and a second power supply unit having a filter. When an irradiation position of the charged particle beam in an ir... | 05/31/2005 |
| 6693390 | Load driving apparatus A load driving apparatus is constituted with a high voltage power source, a low voltage power source, a first switching element, a second switching element, a lamp load, current detecting section, and PWM control section. The first switching element is co... | 02/17/2004 |
| 5912535 | Driving circuit for an electric luminescent panel including first and second driving circuits A circuit driving electric luminescent panel in which the high potential contact of electric luminescent panel is connected to two parallel connected transistors of which the emitter of the first transistor is connected to a current--resisting coil and th... | 06/15/1999 |
| 5896013 | Operating circuit for an inductively ballasted arc discharge lamp Ballast circuitry for a metal halide lamp is disclosed enabling sustained operation with a typical 120 volt AC power source. A novel auxiliary circuit network is operatively associated with inductive type starting circuit means to provide lamp reignition ... | 04/20/1999 |
| 5825133 | Resonant inverter for hot cathode fluorescent lamps A fluorescent lamp drive circuit is disclosed. The fluorescent lamp drive circuit includes first filament drive circuitry coupled to the filaments of the lamp for driving the fluorescent lamp with a first waveform having sufficient amplitude such that gas... | 10/20/1998 |
| 5821696 | Method and circuit to start and operate high pressure discharge lamps Start and operation of high pressure discharge lamps, in which a high-frequency starting voltage UHF and an operating voltage UB are furnished to the lamp electrodes includes the steps of: 1) turning on the high-frequency starting vo... | 10/13/1998 |
| 5313140 | Field emission device with integral charge storage element and method for operation Field emission device apparatus employing an integrally formed capacitance and a switch serially connected between a conductive element and a current source to provide substantially continuous emitted electron current during selected charging periods and ... | 05/17/1994 |
| 5266869 | Discharge lamp lighting apparatus having output impedance which limits current flow therethrough after start of discharging A discharge lamp lighting apparatus comprises a transformer for stepping up an AC power source voltage from an AC power source to produce a high voltage as an output voltage required for lighting a discharge lamp. Particularly, the lighting apparatus furt... | 11/30/1993 |
| 5252891 | Uninterruptible fluorescent lamp circuit available for emergency lighting An uninterruptible fluorescent lamp circuit available for emergency lighting is comprised of an oscillatory boosting circuit which generates a high-frequency, high-voltage power, and a current-limiting circuit which limits current flowing to the fluoresce... | 10/12/1993 |
| 5191261 | Switching power supply for high-voltage flash lamps A flash lamp power supply system, comprising (a) a simmer power supply circuit, comprising (i) a DC simmer power supply, (ii) means for connecting a flash lamp in series with the DC power supply, and (iii) a capacitor connected in parallel to the power su... | 03/02/1993 |
| 5041766 | Power-factor-controlled electronic ballast A self-oscillating half-bridge inverter is powered from a power-line-operated rectifier means providing a DC voltage with a relatively high ripple content. The inverter is loaded by way of a series-tuned high-Q LC cirucit connected across this DC voltage.... | 08/20/1991 |
| 5028844 | DC discharge lamp lighting device A DC discharge lamp lighting device includes a main discharge means providing a main discharge-lamp current to a DC discharge lamp including a filament and at least one anode to form between them a discharge path. The main discharge means comprises means ... | 07/02/1991 |
| 5025197 | Circuit arrangement for A.C. operation of high-pressure gas discharge lamps A circuit arrangement for A.C. operation of high-pressure gas discharge lamps comprising a mains alternating voltage source and a high-frequency oscillator (3) supplied with direct current and which produces a high-frequency current through the lamp super... | 06/18/1991 |
| 5001400 | Power factor correction in electronic ballasts 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... | 03/19/1991 |
| 4985664 | Electronic ballast with high power factor 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 unfilte... | 01/15/1991 |
| 4956581 | Flyback converter microwave oven power supply In a microwave oven, a magnetron is powered by way of a self-oscillating flyback converter circuit, which operates at a conversion frequency controllable over a range of frequencies up to about 35 kHz. The converter circuit is powered from a DC voltage de... | 09/11/1990 |
| 4890041 | High wattage HID lamp circuit A lamp start, hot-restart and operating circuit for a high wattage, high intensity discharge lamp includes cascaded resonant circuits with capacitors and series-connected inductors connected to an AC source. A pulse circuit including two pulse transformer... | 12/26/1989 |
| 4845535 | Light emitting semiconductor device The disclosed light emitting semiconductor device has an n-type (or p-type) base region sandwiched by a p-type (or n-type) emitter region and a p-type (or n-type) collector region. An injecting voltage source is connected across the emittter region and ba... | 07/04/1989 |
| 4818917 | Fluorescent lighting ballast with electronic assist A ballasting circuit for fluorescent lamps includes a series-connected current limiting ballast element and an electronic assist circuit. The ballast element has a high voltage side connectable to a commercial 110 VAC/60 hertz power source and a low volta... | 04/04/1989 |
| 4792727 | System and method for operating a discharge lamp to obtain positive volt-ampere characteristic A system and associated method for operating a gas discharge lamp so as to provide a positive voltage-current characteristic. An AC or DC source is used to provide electron heating, without in itself providing ionization, of the lamp gas. Superimposed on ... | 12/20/1988 |
| 4749913 | Operating circuit for a direct current discharge lamp 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 it... | 06/07/1988 |
| 4749908 | Emergency power supply An emergency power supply including an input for connection to a power line, an output for connecting the input to electrical equipment so as to supply power thereto from the power line, a supplemental power supply connected to the output and adapted to s... | 06/07/1988 |
| 4698518 | Magnetically switched power supply system for lasers A laser power supply system is described in which separate pulses are utilized to avalanche ionize the gas within the laser and then produce a sustained discharge to cause the gas to emit light energy. A pulsed voltage source is used to charge a storage d... | 10/06/1987 |
| 4645981 | Process and apparatus for the surface treatment of workpieces by glow discharge For the glow discharge between a receptacle and a workpiece, the glow discharge path is connected in series with a first switch. A capacitor circuit is charged via the glow discharge path and two diodes. By closing a switch, the previously positive pole o... | 02/24/1987 |
| 4593233 | Lamp drive circuit An alternator circuit comprises an alternator having an armature winding, a field winding, a voltage regulator, a fault detecting circuit, a lamp drive circuit having its input connected to the output of the fault detecting circuit, and a warning lamp dri... | 06/03/1986 |
| 4591764 | Plug-in auxiliary tracks for track lighting systems A relatively light-weight auxiliary power track is adapted to be plugged into and supported by a regular power track in an otherwise ordinary 120 Volt/60 Hz track lighting system. A compact frequency converter is operative to provide 120 Volt/30 kHz high-... | 05/27/1986 |
| 4499533 | Power supply apparatus A power supply apparatus is structured such that the output of an alternating current voltage source (1) is connected to the input of a rectifying circuit (2), a series connection of a first smoothing capacitor (3a), a diode (15) and a second smoothing ca... | 02/12/1985 |
| 4484107 | Discharge lamp lighting device and system In a discharge lamp lighting system comprising a DC or low frequency (LF) AC main source and a high frequency (HF) source, a high frequency component from the HF source and low frequency component from the main source are supplied in an overlapping manner... | 11/20/1984 |
| 4317068 | Plasma jet ignition system An improvement on conventional internal combustion ignition systems, which improvement comprises a capacitor connected parallel to the secondary winding of the ignition transformer, and a bypass circuit through which energy stored in the primary circuit i... | 02/23/1982 |
| 4293797 | Inductive-capacitive cyclic charge-discharge ignition system An inductive-capacitive cyclic charge-discharge ignition system includes an ignition transformer primary winding in parallel with a capacitor and fed by an alternating current source providing a plural number of repetition cycles during each igniter firin... | 10/06/1981 |
