DESCRIPTION

Microsemi’s LX1692F is a cost reduced, third generation CCFL (Cold Cathode Fluorescent Lamp) controller. The integrated controller is optimized to drive CCFL’s using resonant full bridge inverter topology.

Resonant full bridge topology provides near sinusoidal waveforms over a wide supply voltage range in order to maximize the life of CCFL lamps, control EMI emissions, and maximize efficiency.

The LX1692F includes safety features that limit the transformer secondary voltage and protect against fault conditions which include open lamp, and broken lamp faults.

The LX1692F regulates the CCFL brightness in three ways: analog dimming, digital dimming, or combined analog and digital dimming methods simultaneously to achieve the widest dimming range (> 60 to 1).

The LX1692F can accept a brightness control signal that is either an analog voltage or a low frequency PWM.

The LX1692F also features integrated gate drivers for the four external power MOSFETs.

An integrated 4V LDO powering all internal control circuitry greatly simplifies supply voltage requirements.

The LX1692F is available in either a 20-Pin TSSOP or SOIC package.

KEY FEATURES

▪ Low Stress to Transformers

▪ Wide Dimming Range

Analog Dimming: > 3 to 1

Digital Dimming : > 20 to 1

Combined: > 60 to 1

▪ Programmable Burst Dimming Frequency

▪ Programmable Time-Out Protection

▪ Fixed Operating Frequency

▪ Open-Lamp Voltage Protection

▪ Soft Rise/Fall Burst Dimming Control

▪ 3 Tolerance Brightness Reference Voltage

BENEFITS

▪ Even Display Light Distribution

▪ Longer Lamp Life with Optimized

Lamp Current Amplitude

▪ Reduced Operating Voltage

Lowers Corona Discharge and

Prolongs Inverter Life

▪ High “Nits / Watt” Efficiency

Makes Less Heat and Brighter Displays

APPLICATIONS

▪ LCD TV

▪ LCD Monitor