The LED drivers work seamlessly with Atmel AVR? microcontrollers (MCUs), including the Atmel tinyAVR?, Atmel megaAVR? and Atmel AVR XMEGA? devices. The microcontrollers process timing and dimming instructions, sending this data to the MSL2164 and MSL2166 devices. The AVR devices, along with firmware, provide a total solution that optimizes the entire backlight design, delivering superior performance compared to competitive solutions.
Featuring highest efficiency power management and backlight control along with multiple dimming modes for 3D, scanning and zone dimming edge-lit LCD TVs, the MSL2164 and MSL2166 devices drive up to 16 parallel strings of LEDs and offer comprehensive system and fault management to support high-performance backlight design. With this new driver family, high-end TV OEMs can deliver high screen resolution and greatly enhance picture quality using internal lighting timing algorithms that improve the backlight timing accuracy, with higher resolution vs. other solutions on the market today. At the same time, since OEMs will be able to choose from smaller form factor MCUs, such as tinyAVR devices, they can lower their system overhead.
Historically, TV OEMs have had to calculate the appropriate parameters to effectively illuminate a desired area in the backlight of a display. LED drivers would generate algorithms to set the appropriate string phase to optimize synchronization of the backlight to the LCD panel. Often, OEMs had to perform additional calculations to adjust the string phrase to ensure that the backlight was properly synchronized within the frame refresh. The MSL2164 and the MSL2166, with multiple pulse width modulation (PWM) modes—including forward, inverse, trailing and center—reduce design complexity because the timing algorithms are integrated into the devices. This ensures that the backlight is illuminated at the most optimal moment, when all of the LCD pixels have settled.
"Next-generation TVs, particularly those with 3D displays, demand a different approach towards local dimming," said Girish Ramesh, marketing manager of smart power products at Atmel Corporation. "Our newest LED drivers, the MSL2164 and the MSL2166, with their smart timing algorithms and programmable PWM modes, give OEMs who are developing LED edge-lit TVs a clear advantage in performance, design time and cost."
Minimize Power, Maximize Backlight Performance
The MSL2164 and MSL2166 devices drive external MOSFETs with high current accuracy and string matching. By offering the widest dimming resolution in Atmel's LED driver product family, the devices increase the contrast ratio and reduce power consumption by at least 20% compared to other available solutions.
12-bit PWM string dimming, which allows 4,096 gray scales for an enhanced image
8-bit global intensity dimming
12-bit PWM string phrasing
10-bit digital-to-analog converter (DAC) current control, which increases dimming LED driver control in lower light conditions
8-bit adaptive power correction, which maximizes efficiency of up to 3 string power supplies
An on-chip EEPROM allows OEMs to pre-program key system parameters to allow multiple subframes and reduce overall system design complexity and cost. The LED drivers feature Efficiency Optimizers that adaptively control up to three DC-DC converters that power the LED strings, minimizing power while maintaining LED current accuracy.
Availability and Pricing
Production volumes of the MSL2164 and the MSL2166 are available now, with prices at $5.95 for quantities of 1K.
About Atmel
Atmel Corporation (Nasdaq: ATML) is a worldwide leader in the design and manufacture of microcontrollers, capacitive touch solutions, advanced logic, mixed-signal, nonvolatile memory and radio frequency (RF) components. Leveraging one of the industry's broadest intellectual property (IP) technology portfolios, Atmel is able to provide the electronics industry with complete system solutions focused on industrial, consumer, communications, computing and automotive markets.
LED driver compatible with triac dimming
Fairchild Semiconductor has developed the FL7730 single-stage primary side regulation (PSR) controller with power factor correction (PFC), TRIAC and analog dimming compatibility, as well as the FL7732 for non-dimming applications.The FL7730 is an active PFC controller for single-stage flyback topology application. The device supports both TRIAC and analog dimming. Implemented with Fairchild's unique analog sensing technology, the device can achieve TRIAC dimming control without flicker over the full range of 0 to 100% light output.
The FL7730 and FL7732 combine primary-side regulation and a single-stage PFC topology to minimize total bill-of-material (BOM) count, such as an input electrolytic capacitor and feedback circuitry.
To improve power factor and THD, both devices feature constant on-time control with an internal error amplifier and low bandwidth compensator. Precise Constant Current accuracy/control (± 5 percent) regulates accurate output current, independent of input and output voltage, allowing designers to achieve high and improved lighting quality. Operating frequency is proportionally adjusted by output voltage in both devices to guarantee DCM operation with optimized PF/THD and simpler design.
PF (=0.9), low total harmonic distortion (THD) (Class C) and power efficiency of up to 85 percent for the FL7730 - greater than 85 percent for the FL7732 in non-dimming applications - allows these devices to meet worldwide energy saving regulations.
