Power source apparatus
US7619368B2 · kind B2 · utility
Inventor
Key dates
| Filing date | Jul 5, 2005 |
| Grant date | Nov 17, 2009 |
| Priority date | — |
| Expiry date | Feb 24, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/00
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A power source apparatus is disclosed in this invention, specifically a power source apparatus comprising a voltage amplitude control unit that employs an active power factor corrector to control the output DC voltage by applying positive or negative logic control voltage, incorporated with high frequency power source circuit and high frequency transformer, brightness of Cold Cathode Fluorescent Lamp (CCFL) or External Electrode Fluorescent Lamp (EEFL) are controllable and DC power is directly applied to DC load. Such method is accomplished by adjusting the amplitude of the supplying DC voltage for controlling the amplitude of the high frequency voltage of CCFL or EEFL, thus called Voltage Amplitude Method. Because of the characteristics of stable frequency, high resolution and linearity, VAM is broadly used in the control of luminance of discharge tubes, such as TFT-LCD TVs, LCD monitors and advertisement lamps. The impulse width controller of the present invention achieves the luminance control of CCFL or EEFL inside or outside the glow discharge zone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.