这种小外形封装的新型驱动器提供CABC模式和自动调光功能；进一步拓宽了该公司的白光LED背光产品线

致力于为工业和通信行业的客户提供电源创新解决方案的AnalogicTech™（Nasdaq：AATI）日前推出AAT2868和AAT2869 LED背光驱动器。AAT2868和AAT2869是1x/1.5x双模、基于电荷泵的高效白光LED背光驱动电路，可同时驱动四个恆流LED通道，并提供CABC（content adaptive brightness control）或DBC（dynamic backlight control），将能耗进一步降低了50%。为形成完整的照明解决方案，两电路都带有两个低压差（LDO）线性稳压器。

“手持装置中采用白光LED技术所面临的两大关键问题就是能耗和不同亮度级别实现平滑转换，”AnalogicTech的显示与照明产品线总监Phil Dewsbury表示，“消费者要求电池寿命长，以及更好的用户体验，我们新推出的产品的特徵在这些方面具备优势。CABC功能能将能耗降低高达50%，而自动LED渐暗功能克提高用户满意度，同时还通过转移LED电流渐小的通信和计时的负担，简化了编程。”

在CABC和调光功能方面，AAT2868为用户提供脉宽调制（PWM）调光输入进行外部亮度和渐暗控制，同时通过AS2CwireTM界面完全控制32档LED电流的按比例变化。 AAT2869拥有不是手动PWM输入，而是基于AS2C的自动调光和渐暗功能，降低了对系统资源的要求。 AAT2869具备自动调亮和调暗的功能,背光的开啟和关闭具有视觉舒适感。这两种背光驱动电路都通过允许系统根据显示图像持续调节背光电流大小，从而更大地减少了能耗。

AAT2868 Key Features and Benefits:
•    2.7V to 5.5V Supply Voltage Range
•    Dual Mode 1x/1.5x Charge Pump for LED Driver
o    Drives Up to 4 LEDs with up to 31mA each
•    Linear LED Output Control Options
o    Max Current Set by AS2C wire with 32 Step Control
o    PWM Interface Dimming from 100% to 1% Duty Cycle with Frequency up to 100kHz
•    Charge Pump 0.9MHz Constant Switching Frequency
•    Automatic Soft-Start Limits Inrush Current
•    Dual 150mA LDOs
o    Enable and Output Voltage Set by AS2Cwire: 16 Combinations of 5 Output Voltages: 1.2V, 1.5V, 1.8V, 2.8V, & 3.0V
o    Integrated Discharge Resistor when Disabled
•    < 1.0microA in Shutdown
•    Short-Circuit Protection
•    -40°C to 85°C Temperature Range
•    TQFN3.0x2.2-18 Package

AAT2868 Typical Application

AAT2869 Key Features and Benefits:
•    2.7V to 5.5V Supply Voltage Range
•    Dual Mode 1x/1.5x Charge Pump for LED Driver
o    Drives Up to 4 LEDs with up to 31mA each
•    Linear LED Output Control Options
o    Max Current Set by AS2C wire with 32 Step Control
o    Programmable Fade-In and Fade Out
•    Charge Pump 0.9MHz Constant Switching Frequency
•    Automatic Soft-Start Limits Inrush Current
•    Dual 150mA LDOs
o    Enable and Output Voltage Set by AS2Cwire: 16 Combinations of 5 Output Voltages: 1.2V, 1.5V, 1.8V, 2.8V and 3.0V
o    Integrated Discharge Resistor when Disabled
•    < 1.0microA in Shutdown
•    Short-Circuit Protection
•    -40°C to 85°C Temperature Range
•    RoHS Compliant, Halogen-Free TQFN3.0x2.2-18 Package

AAT2869 Typical Application