STMicroelectronics' Backlight Driver for High-Tech Mobile Devices: Saving Power, Time, and Cost

Small control IC for energy-efficient white-LED backlights, simplifying circuit design

Korea, October 4, 2011 – STMicroelectronics ( www.st.com ), a world-leading integrated semiconductor company, has expanded its portfolio of energy-saving solutions for mobile devices by launching a new IC that simplifies the design of power-efficient LCD and keypad backlights that make up white LEDs.

Backlights based on white LEDs, replacing conventional fluorescent lamps, extend the battery life of portable devices such as smartphones, game consoles, and GPS terminals by consuming relatively low power. ST’s new STLA02 chip further enhances backlight design by performing an upper current sensing function; this allows the backlight negative (lower) terminal to be directly connected to ground, eliminating the need for a lower sensing connection. This simplifies PCB design and improves system reliability by reducing wired connections in the backlight.

STLA02 can drive up to 6 LEDs and can operate with a minimum supply voltage of 2.5V, allowing it to operate even in systems powered by only one lithium battery. It supports a maximum input voltage of 18V, making it suitable for various battery types.

STLA02 expands ST’s diverse product portfolio that supports reduced size and extended battery life by utilizing in-house process technology capable of delivering the highest integration density and power efficiency. These products include high-efficiency DC-DC converters, audio ICs and Class-D amplifiers, ambient light sensors, motion sensors, and high-performance, low-power microcontrollers such as the STM8 and STM32 families.

Main features of STLA02:
• Boost (Step-up) DC-DC Converter Topology
• Battery supply voltage range from 2.5V to 18V
• Maximum LED driving voltage: 27V
• Output current: 20mA per LED
• Switching frequency: 2.3MHz
• PWM dimming range: 300:1
• Enable pin providing high-speed response characteristics through current mode regulation
• Equipped with overheating and overvoltage protection

STLA02 is being mass-produced in DFN-6L packages, and the price per unit is $0.892 based on a supply volume of 1,000 units. Separate price adjustments are available for bulk orders.