AnalogicTech Introduces New Photo Flash & LED Backlight Driver ICs
Advanced Analogic Technologies Inc. (AnalogicTech™) announced a new set of flash and backlight White LED (WLED) drivers for the highly competitive feature phone market. Offering new efficiencies in power usage in highly compact packages, the AAT3176 flash driver and the AAT3351 white LED driver promise to help handset designers extend battery life and reduce product footprint.
"Over the last few years AnalogicTech has built up a comprehensive product line of lighting solutions for cell phone and mobile device designs by constantly pursuing innovative approaches to the problems designers face," said Phil Dewsbury, Product Line Director for AnalogicTech. "By improving power efficiency, reducing board footprint and simplifying LED control while preserving the flexibility and safety features in our existing products, these two new charge pump-based devices take those achievements to a new level."
Operating from a 2.7 to 5.5V input voltage, the AAT3176 flash driver IC supplies up to 500mA output current. The dual mode charge pump maximizes power efficiency by supporting both 1 and 2X operation and can be programmed across 16 distinct steps via AnalogicTech’s patented S²Cwire™ (Simple Serial Control) interface. Coming in the industry’s smallest package for a 500 mA flash driver IC – 20% smaller than comparable devices – the AAT3176 allows designers to build highly compact camera lighting solutions.
To maximize design flexibility and minimize programming time, the AAT3176 uses separate external resistors to set maximum flash and movie-mode current. To protect the integrity of the device, the driver features a thermal management system that includes open- and short-circuit protection and automatic soft-start circuitry. A load disconnect feature extends battery life by disconnecting the load during shutdown and reducing quiescent current to less than 1.0µA.
The AAT3351 is a high efficiency charge pump capable of driving up to 4 White LEDs at up to 30mA each. The dual-mode fractional charge pump automatically switches between 1X and 1.5X modes based on input voltage, LED forward voltage and load current to maximize efficiency. A 1 MHz switching frequency helps minimize external component size.
To smooth transitions between brightness levels, the device uses AnalogicTech’s S2Cwire™ serial digital interface to enable, disable and set current to any of 32 levels. LED current output accuracy is +/-10% and LED current matching is 3%. The AAT3351 also adds automatic soft-start circuitry and built-in short-circuit protection.
Both ICs are qualified across the -40 to +85°C temperature range. The AAT3176 is available in a compact 2.2 x 2.2-mm, 10-pin TDFN package and sells for $0.66. The AAT3351 comes in either a 14-pin TSOPJW or 12-pin TDFN33 package and sells for $0.48 in 1K quantities.
