AAT2822 TFT-LCD DC/DC Converter with WLED Driver and VCOM Buffer
The AAT2822 is a highly integrated charge pump-based lighting management unit (LMU) providing eight independently configurable LED channels that can also be grouped into main or sub backlight controls. The built-in support for low cost ambient light sensors automates all brightness adjustments. In addition, four programmable low dropout (LDO) linear regulators are provided to supply other lighting and camera module functions. The LMU is optimized for single-cell lithium-ion/polymer systems making it ideal for portable devices. A tri-mode negative charge pump provides power to backlight LEDs with improved efficiency over conventional charge pump topologies. All eight backlight LED current sinks are programmable up to 27.9mA. LEDs may be set individually or in groups for various arrays of backlight or keypad lighting applications. High frequency PWM dimming for both Main and Sub display backlighting is provided and is compliant to Content Adaptive Brightness Control (CABC) specifications with a PWM frequency up to 100 kHz. The ambient light control features automatic sensor calibration and 50Hz/60Hz noise rejection for accurate brightness adjustment without processor intervention. All AAT2822 functions are programmed using an industry standard bi-directional I2C interface. This interface can enable, disable, and set the backlight current to one of 32 levels (5 bits) for the backlight. Backlight current matching is better than ±3% for uniform display/subdisplay brightness. The AAT2822 also contains four high-performance lownoise, low dropout (LDO) linear regulators. Each regulator starts up with a default 1.2V and is adjustable by programming through the I2C interface. LDOA can supply up to 300mA, while LDOB, C and D can source up to 150mA to a system load.
技术特性
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应用领域 APPLICATION
订购信息 Ordering Information
AAT2822 典型应用
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| 应用技术支持与电子电路设计开发资源下载 | 版本信息 | 大小 |
| AAT2822 数据资料DataSheet下载:pdf | Rev.V2 | 2 页 |
