Design of the backlight inverter for multi-lamp driving

As a LCD monitor is larger and thinner, a Cold Cathode Fluorescent Lamp (CCFL) for backlight in LCD monitor gradually becomes longer and thinner. The backlight of a large LCD monitor, however, has a limitation in its brightness In this study, a parallel multi-lamp is used in order to supply enough brightness Though the CCFLs are made through a detail and equal manufacturing process, they don't have exactly the same features individually in their brightness, frequency, voltage and current. Consequently, it is difficult to have equal brightness at an early lighting condition or during lighting time In this paper, a parallel multi-lamp which can have the same output under the same condition is designed. For this, 18 inch LCD monitor with four lamps is used An inverter for multi-lamp driving is also used in this study The newly designed inverter shows more than 90% efficiency in its brightness input and output Besides, it is also available for a multi-drive of other lamps.