CCFL Controller ICs Information
CCFL controllers provide control functions for the direct-drive inverters that are used to operate cold cathode fluorescent lamps (CCFL). A CCFL consists of a phosphor-coated glass cylinder with cathodes at each end. Cold cathode light is used mainly for CCFL backlight or edge-lighting of liquid crystal flat panel displays (LCFPD). With a CCFL controller, the lamp filament does not require preheating and the electrodes in the bulb are maintained at low temperatures. CCFL inverters and CCFL capacitors are important parts of CCFL controllers. A CCFL inverter is the cold cathode lighting source used to drive the CCFL. A CCFL capacitor allows the output voltage from the transformer to be applied to the electrodes.
Selecting CCFL controllers requires an analysis of performance specifications and product features. Important specifications include:
- voltage rating
- current rating
- switchover efficiency
Voltage rating is the highest voltage that may be continuously applied conforming with standards or specifications. Current rating is the maximum current that CCFL controllers are designed to carry or produce. A typical CCFL inverter has a switchover efficiency that exceeds 80%. Some CCFL controllers have sound and switch controls. Others allow for brightness adjustments. Energy-efficient CCFLs provide high efficiency and brightness, but consume less power. A CCFL backlight provides a consistent, bright light.
CCFL controllers are used in computers, mobile phones, video games, notebook LCD displays, desktop flat panel displays (FPD), and in various illumination and lighting devices.
CCFL controllers and cold cathode lighting systems should be certified by an organization such as Underwriters Laboratories (UL). The C-UL US listing mark indicates compliance with both Canadian and U.S. requirements. UL encourages manufacturers with products certified for both countries to use this optional mark; however, they may also use separate UL marks for the United States and Canada. In Europe, CCFL controllers may bear the CE mark to indicate compliance with relevant European Union (EU) directives.