OZ965
High-Efficiency Inverter Controller
FEATURES
• • • • • • • • • • Single-stage power conversion, requiring only a +...
OZ965
High-Efficiency Inverter Controller
FEATURES
Single-stage power conversion, requiring only a +5 V
voltage source Reduces the number of components and board size by 30% compared with conventional design Supports both floating and grounded secondary designs 90% efficiency vs. typical 75% efficiency of conventional designs Internal open-lamp and short-circuit protections Wide dimming range Supports multiple CCFLs Simple and reliable 2-winding transformer design Eliminates leakage current when used in a floating secondary design Constant-frequency design eliminates interference with LCDs dimming function with an analog
voltage or low frequency Pulse Width Modulation (PWM) control. Operating Principle: The CCFL tube, transformer secondary, and capacitor form a resonant circuit. The OZ965 utilizes the low energy loss resonate mode principle to deliver a very high efficiency inverter. The OZ965 drives the transformer primary with a variable pulse width
voltage directly from the +5v supply. The resultant primary drive current is alternately reversing with zero-
voltage-switching. Because of the transformer leakage inductance and the secondary resonant circuit, the secondary
voltage and current are approximately sinusoidal. This sinusoid results in very little harmonic emi/rfi emissions. The OZ965 operates at a single, constant frequency in a PWM mode. Typical operating frequency ranges between 30 KHz to 200 KHz, dependent upon the CCFL and transformer charact...