
Microsemi Corporation
DESCRIPTION
The LX1697 is a high performance CCFL controller optimized for wide input voltage range notebook display back lighting applications. Its brightness control architecture supports Intel’s DPST (Display Power Saving Technology) that adjusts the brightness as a function of video
content.
Digital Dimming duty cycle is controlled by providing either a dc voltage or a digital PWM signal to the BRITE_D pin. Burst frequency can be controlled either by the on chip burst oscillator or directly by a low frequency PWM logic signal at BRITE_D.
The LX1697 includes a built in 5.1V regulator so it can be operated directly from the battery without the need of an external 5V supply from the system. The controller’s power stage consists of direct coupled full bridge high voltage drivers for the external N-channel high side and N
channel low side power FETs.
KEY FEATURES
7 to 25 Volts Wide Input Voltage Range
Resistor Programmable Lamp Operating Frequency within ±3% Tolerance
Resistor Programmable Burst Operating Frequency
Support IntelTM DPST for System PWM input
Compatible with Microsemi’s new SMBus CCFL controllers
Fully Programmable Open Lamp and Load Fault Time Outs
On Chip Full Wave Rectifiers for Lamp Voltage and Current
Cost Effective and Low Parts Count Inverter Modules
Uses Industry Standard High Voltage Transformers
APPLICATIONS
Note Book LCD displays
Transportable Computers
Web Tablet LCD displays