Texas Instruments UCC2972N

Description
The UCC3972/3 BICMOS Cold Cathode Fluorescent Lamp (CCFL) controllers are designed for use in notebook computers and portable applications. They provide the necessary circuit blocks to implement a highly efficient CCFL backlight power supply in a small footprint 8-pin TSSOP package. The controllers typically consume less than 1mA of operating current, improving overall system efficiency.
The UCC3972/3 controllers integrate features such as a feedback-controlled PWM driver stage, open lamp protection, startup delay, and synchronization circuitry between the buck and push-pull stages. They include an internal shunt regulator, allowing them to operate with input voltages from 4.5V to 25V. The controllers support both analog and externally generated low-frequency dimming modes of operation.
The UCC3973 adds a programmable voltage clamp at the BUCK pin to protect the transformer from overvoltage during startup or when an open lamp occurs.

Features
1mA typical supply current
Accurate lamp current control
Analog or low-frequency dimming capability
Open lamp protection
Programmable startup delay
4.5V to 25V operation
PWM frequency synchronized to external resonant tank
8-pin TSSOP and SOIC packages available
Internal voltage clamp protects transformer from over-voltage (UCC3973)

Applications
Notebook computers
Portable applications
CCFL backlight power supplies