Driver IC improves backlight design

STMicroelectronics NV has introduced a driver IC that simplifies the design of LCD and LED backlight. The STLA02 expands ST's line of energy-saving solutions for mobile devices.

Backlights built with white LEDs consume less power, enabling longer battery life for portable devices such as smartphones, games and GPS terminals, the company stated. The STLA02 improves backlight design by performing high-side current sensing. This allows the backlight negative (low-side) terminal to be connected directly to ground with no need for a low-side sensing connection. This simplifies PCB design, reduces wired connections to the backlight and increases system reliability.

The STLA02 can drive up to six LEDs and can operate from a supply voltage as low as 2.5V, allowing it to be used in systems powered by only a single lithium cell. The 18V maximum input voltage also allows the IC to be used with other battery types.

The IC extends ST's portfolio of devices that help reduce size and increase battery life in feature-rich portable products. These include highly efficient DC/DC converters, audio ICs and class-D amplifiers, ambient light sensors, motion sensors and high-performance low-power MCUs such as the STM8 and STM32 families.

The STLA02 features maximum LED driving voltage of 27V, output current of 20mA per LED and switching frequency of 2.3MHz. It has a PWM dimming range of 300:1. Additionally, the IC can enable pin with fast response due to current-mode regulation and has a built-in overtemperature and overvoltage protection.

The STLA02 is in full production in six-lead DFN6 package, priced from $0.892 for orders of more than 1000 units. Alternative pricing options may be available for larger quantities.