STMicroelectronics has extended its portfolio for mobile devices with an IC that simplifies the design of LCD and keypad backlights comprising white LEDs.
According to the company, backlights built with white LEDs, instead of traditional fluorescent tubes, consume less power enabling long battery life for portable devices such as smartphones, games and global positioning system terminals. The company's latest chip, the STLA02, enhances backlight design further by performing high-side current sensing, which allows the backlight negative terminal to be connected directly to ground with no need for a low-side sensing connection, claims the company.
The chip can drive up to six LEDs and can operate from a supply voltage of 2.5V, allowing its use in systems powered by a single lithium cell. The maximum input voltage of 18V also allows use with many battery types. The chip's portfolio includes DC/DC converters, audio ICs and class-D amplifiers, ambient light sensors, motion sensors, and STM8 and STM32 microcontrollers.
The chip features a boost or step-up DC/DC converter topology and its battery supply voltage ranges from 2.5 to 18V. It has a maximum LED driving voltage of 27V and output current of 20mA per LED. It features 2.3MHz switching frequency and 300:1 PWM dimming range. The chip enables pin with fast response due to current-mode regulation. It also features built-in over-temperature and over-voltage protection. The chip is available in the six-lead DFN6 package.
