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| Number | Title | Issue Date |
| 7843142 | Pulse width modulation apparatus and apparatus for driving light source having the same Provided are a pulse width modulation (PWM) apparatus and a light source-driving apparatus including the PWM apparatus. The PWM apparatus includes a voltage division part, a capacitor part, a first operational amplifier, a first noise reduction part, and a second op... | 11/30/2010 |
| 7443102 | Energy-conserving devices of illumination systems Disclosed is an energy-conserving device for an illumination system. The energy-conserving device is connected between a power supply of and a lighting assembly of the illumination system. The energy-conserving assembly provides a first switch, a ballast, and a comp... | 10/28/2008 |
| 5917290 | Parallel-storage series-drive electronic ballast An electronic ballast is provided for converting an AC voltage and current, supplied by a power source such as a power line, to an alternating square-wave voltage and current having the same frequency, for supply to a discharge lamp. The ballast includes ... | 06/29/1999 |
| 5387847 | Passive power factor ballast circuit for the gas discharge lamps A ballast for a gas discharge lamp circuit has a d-c output which contains three series-connected diodes connected across the output terminals, a pair of capacitors connected from different respective nodes of the diodes to respective ones of the output t... | 02/07/1995 |
| 4766352 | Method and apparatus for starting and operating fluorescent lamp and auxiliary ballast systems at reduced power levels A low cost circuit addition in the form of a capacitor of suitable value provides effective starting and operation of rapid start, preheat, and instant start fluorescent type gas discharge lamps along with their standard A.C. operated ballast transformer ... | 08/23/1988 |
| 4748381 | Circuit arrangement for A.C. operation of gas discharge lamps 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 convert... | 05/31/1988 |
| 4667131 | Protection circuit for fluorescent lamp ballasts In a series-resonant-loaded inverter-type electronic ballast for two rapid-start fluorescent lamps, in order to meet requirements for safety from electric shock hazard, as well as to protect the inverter circuit from over-load, means are provided by which... | 05/19/1987 |
| 4488091 | High intensity discharge lamp A high intensity discharge lamp operable from an AC potential source includes an arc discharge tube having a pair of oppositely disposed main electrodes therein and an associated external starting electrode, all disposed within a sealed envelope having an... | 12/11/1984 |
