16串LED驱动器应用案例精讲

MSL2164和MSL2166器件可在新型3D和2D滚动背光TV中提供极具吸引力的观看和视频游戏体验。 
 
这些LED驱动器可与爱特梅尔tinyAVR®、megaAVR®和AVR XMEGA等AVR®微控制器(MCU) 无缝集成。微控制器处理定时和调光指令，将数据发送给MSL2164和MSL2166器件。 AVR器件与固件提供优化整个背光设计的总体解决方案，提供相比竞争解决方案更卓越的性能。
 
MSL2164和MSL2166器件具有最高效的功率管理、背光控制，以及用于3D、扫描和区域调光侧光LCD TV的多重调光模式，可以驱动多达16个并联LED串，提供全面的系统和故障管理，以支持高性能背光设计。采用这一新驱动器系列，高端电视OEM厂商能够使用改善背光定时精度的内部照明定时算法，提供高于现今市场上其它解决方案的分辨率，以实现高屏幕分辨率，并大幅提升图像质量。同时，OEM厂商能够选择外形尺寸更小的MCU如tinyAVR器件，来降低系统开销。
 
过去，TV OEM厂商必须计算合适的参数，以便有效地照亮所要求的显示屏背光区域。LED驱动器将生成算法以设置合适的LED串相位，优化背光与LCD面板的同步。 OEM厂商必须经常执行附加算法以调节LED串相位，确保背光在帧刷新期间完全同步。MSL2164和MSL2166具有多种脉宽调制(PWM)模式， 包括正向、逆向、拖尾和中心，由于新器件中集成了定时算法，设计复杂性得以降低，这确保背光在所有LCD像素已经稳定的最佳时刻照亮。
 
The MSL2164/MSL2166 compact, high-power LED string drivers use external current control MOSFETsto sink up to 350mA per string, with matching better than ±0.8%. The MSL2164/MSL2166 drive 16 parallel strings of LEDs and offer fault detection and management of open-circuit and short-circuit LEDs.
 
The MSL2164/MSL2166 feature a 20MHz SPI serial interface. Both devices support video frame-by-frame LED string intensity control for up to eightinterconnected devices, allowing active area dimming and phase-shifted PWM outputs. They also include an advanced PWM engine that synchronizes PWM dimming to the video signal supporting forward, center, reverse and inverse PWM modes for reduced motion blur and waterfall noise.
 
The MSL2164/MSL2166 adaptively control any topology DC-DC or AC/DC converter that power the LED strings. The patent-pending “Efficiency Optimizers” minimize power use while maintaining LED current accuracy.
 
A unique combination of LED current control and pulse width dimming management offers simple full-screen brightness control, versatile area dimming and a consistent white point. Full-scale LED regulation current is set for each string using current sense resistors and a 10-bit register that controls global string current. The 12-bit global intensity register controls PWM dimming of all strings, and each string uses a 12-bit register to control individual string PWM
dimming.
 
The MSL2164/MSL2166 monitor the LED strings for open-circuit, short-circuit, loss-of-sync and over-temperature faults, and provide a hardware fault output (FLTB) to notify the microcontroller. Detailed fault status and control are available through the serial interface. Additionally, the MSL2164/MSL2166 include on-chip EEPROMs that allow customizing of the register power-up states via the serial interface.
 
The MSL2164/MSL2166 are offered in a 9 x 9 x 0.85mm, 64-pin TQFN package and operate over the -40°C to 85°C temperature range.
 
 
典型应用电路
 
应用：
Long-Life, Efficient LED Backlighting for:
Televisions and Desktop Monitors
Medical and Industrial Instrumentation
Automotive Audio-visual Displays Channel Signs Architectural Lighting