16串LED驅(qū)動(dòng)器應(yīng)用案例精講

MSL2164和MSL2166器件可在新型3D和2D滾動(dòng)背光TV中提供極具吸引力的觀看和視頻游戲體驗(yàn)。?
?
這些LED驅(qū)動(dòng)器可與愛特梅爾tinyAVR?、megaAVR?和AVR XMEGA等AVR?微控制器(MCU) 無縫集成。微控制器處理定時(shí)和調(diào)光指令，將數(shù)據(jù)發(fā)送給MSL2164和MSL2166器件。 AVR器件與固件提供優(yōu)化整個(gè)背光設(shè)計(jì)的總體解決方案，提供相比競爭解決方案更卓越的性能。
?
MSL2164和MSL2166器件具有最高效的功率管理、背光控制，以及用于3D、掃描和區(qū)域調(diào)光側(cè)光LCD TV的多重調(diào)光模式，可以驅(qū)動(dòng)多達(dá)16個(gè)并聯(lián)LED串，提供全面的系統(tǒng)和故障管理，以支持高性能背光設(shè)計(jì)。采用這一新驅(qū)動(dòng)器系列，高端電視OEM廠商能夠使用改善背光定時(shí)精度的內(nèi)部照明定時(shí)算法，提供高于現(xiàn)今市場上其它解決方案的分辨率，以實(shí)現(xiàn)高屏幕分辨率，并大幅提升圖像質(zhì)量。同時(shí)，OEM廠商能夠選擇外形尺寸更小的MCU如tinyAVR器件，來降低系統(tǒng)開銷。
?
過去，TV OEM廠商必須計(jì)算合適的參數(shù)，以便有效地照亮所要求的顯示屏背光區(qū)域。LED驅(qū)動(dòng)器將生成算法以設(shè)置合適的LED串相位，優(yōu)化背光與LCD面板的同步。 OEM廠商必須經(jīng)常執(zhí)行附加算法以調(diào)節(jié)LED串相位，確保背光在幀刷新期間完全同步。MSL2164和MSL2166具有多種脈寬調(diào)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時(shí)算法，設(shè)計(jì)復(fù)雜性得以降低，這確保背光在所有LCD像素已經(jīng)穩(wěn)定的最佳時(shí)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.
?
?
典型應(yīng)用電路
?
應(yīng)用：
Long-Life, Efficient LED Backlighting for:
Televisions and Desktop Monitors
Medical and Industrial Instrumentation
Automotive Audio-visual Displays Channel Signs Architectural Lighting
?
?
?