Advanced Analogic Technologies (AnalogicTech) has introduced five tri-mode, high-effficiency charge pumps for white LED backlight and colour LED applications. Complementing the company's extensive line of existing white LED drivers, the new MT3151/2/3/6 family and MT3129 devices allow AnalogicTech to offer a complete lighting solution for handsets including drivers for white LED backlight, RGB LEDs, and camera flash solutions.
The MT3151/2/3/6 products represent AnalogicTech's first family of current sink LED drivers. Designed to meet the wiring requirements of second generation display modules, the tri-mode devices combine a load switch (1X) and a high-efficiency (1.5X or 2X) charge pump with an internal sensing circuit that monitors the required voltage on each constant current sink input. The load switch and charge pump modes are set based on the input battery voltage and current sink input voltage. All products in the family are able to control currents down to 50A. This feature is especially important when controlling fully transmissive displays that need a backlight to allow the user to see images on the display. Accordingly, in standby mode there is still a requirement to have current flowing through the white LED. This clearly affects the battery lifetime, so AnalogicTech's low minimum current feature in these parts is an important benefit to both designers and end users, particularly as fully transmissive displays are on the increase.
The devices can drive four or six individual LEDs with a maximum current of 30mA per channel. To control the current level for the LED channels, different devices in this product family feature AnalogicTech's proprietary S2Cwire (Simple Serial Control) or AS2Cwire (Advanced Simple Serial Control) interface. These unique interfaces simplify design and lower system costs by managing control and signalling over a single wire connectien.
Advanced Analogic Technologies, Theale, Berkshire RG7 4TY, UK.www.analogictech.com