A High-Voltage Input Backlight Module Driver for Multi-Lamp LCD Panels

A high-voltage DC input backlight module driver for multi-lamp LCD panels is presented in this paper. The 400-V DC output of a power factor corrector (PFC) is directly coupled to a class-D resonant inverter. Thus the requirement of a buck converter conventionally adopted to provide a low input voltage for the DC/AC inverter is eliminated. Also a single transformer with multiple secondaries is utilized to drive multiple lamps. The proposed backlight module driver features less circuit components, a lower cost and a higher efficiency. Design considerations are discussed and design procedures are derived. Simulations and experimental results confirm with the theoretical analysis.