小型液晶显示器背光led驱动系统

　　小型液晶显示器背光led驱动系统

　　把一个系统级的方法来驱动LED液晶背光是小格式。

　　发光二极管（LED）技术被广泛应用于为电池供电的小型液晶显示器（LCD）中的像素提供照明。发光二极管发出的白光通过偏光镜传递到LCD，在那里液晶可以被阻挡或衰减，并发送到RGB彩色滤光片上以产生彩色光。

　　Figure 1 shows a system-level view of a backlight LED driver which consists of a DC/DC converter and one or more regulated current sources. Moreover， RGB-LED-based backlights require a temperature based feedback control， which translates to a much higher cost than white-LED-based backlights. How much PCB area can be used？ What features are needed？ How much power will the system consume？ Answering these questions can guide the designer in the selection of the appropriate backlight LED driver.

　　DC/DC converters for LED backlight

　　In portable applications with a single-cell Li-Ion source， the sum of the voltage drop across the white， green， or blue LED and the current source can be lower or higher than the battery voltage. This means that， whereas a red LED can be powered directly from a single-cell Li-Ion battery， a white， blue， or green LED requires the battery voltage to be sometimes boosted.