AnalogicTech Intros AAT2806 Dual-Mode Charge Pump
Advanced Analogic Technologies Inc. (AnalogicTech, Sunnyvale, CA), a developer of power management solutions, introduced the AAT2806, a dual-mode, high-efficiency charge pump that supports both white LED backlight and camera flash applications for portable systems that run on lithium-ion/polymer batteries. The new device uses AnalogicTech’s single-wire Simple Serial Control™ (S2Cwire™) serial digital interface to enable, disable, and set current settings across an eight-level logarithmic scale, offering independent control of LED backlight and camera flash functions.
To minimize backlight power consumption during operation, the device adds a light load mode with quiescent current as low as 50 µA (typical). The backlight charge pump in the AAT2806 drives up to four LEDs at a total output of 80 mA. Current sinks may be operated individually or in parallel to drive higher current LEDs. The charge pump maximizes power efficiency by operating in 1X, 1.5X, and 2X modes. The device automatically selects the lowest power mode by comparing the forward voltage of each LED with the input voltage. Low on-resistance of the current sinks minimizes the voltage headroom required to drive each LED and helps increase the amount of time the devices stays in 1X mode before transitioning to 1.5X mode.
The AAT2806 is available in a lead-free, thermally enhanced, 16-pin TDFN44 package, and is qualified across the -40 °C to +85 °C range. The device sells for $1.60 in 1,000-unit quantities.
