
Microsemi Corporation
DESCRIPTION
The LX1693 is a high performance CCFL controller optimized for wide input voltage range notebook display back lighting applications. Its new brightness control architecture provides versatile support for ambient light sensor (ALS) control of panel brightness. It also supports Intel’s DPST (Display Power Saving Technology) that adjusts the brightness as a function of video content. The ALS control architecture is compatible with all Microsemi visible light sensor products.
The controller’s digital dimming mode includes three brightness inputs: ALS_IN for the light sensor, BRITE_D for brightness and BST_SYNC for digital dimming and synchronization..
Burst frequency can be controlled either by the on chip burst oscillator or directly by an external logic signal at BST_SYNC. The on chip burst oscillator can either free run or synchronize to an external signal. Digital Dimming duty cycle is controlled by providing either a DC voltage or a PWM signal to the BRITE_D pin. The LX1693 can be operated directly from the battery without the need of an external 5V supply from the system.
KEY FEATURES
■ 7 to 25 Volts Wide Input Voltage Range
■ Versatile Support for Ambient Light Sensor Brightness Control
■ Resistor Programmable Lamp Operating Frequency within ±4% 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