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Atmel LED Driver-MSL3085

General Description

The Atmel LED Driver-

MSL3085 compact, high-

power 8 LED strings controller

uses external MOSFETs to sink

up to 350mA per string, with

current accuracy and matching

better than ±1.5%. The

MSL3085 drives eight parallel

strings of LEDs, and offers fault

detection and management of

open and short circuit LEDs.

Atmel LED Driver-MSL3085

8-string White and RGB LED Driver with Adaptive Power

video frame-by-frame LED string intensity control for up to eight

interconnected devices, allowing active area dimming and phase shifted

PWM timing for video displays. It includes an advanced PWM engine that

synchronizes LED timing with the video signal for reduced motion blur and

waterfall noise.

The MSL3085 adaptively controls the DC-DC converters that power the LED

strings using patented Atmel Adaptive SourcePower™ technology. These

fault monitored efficiency optimizers minimize power use while maintaining

LED current accuracy, and allow up to eight interconnected devices to

automatically negotiate the optimum power supply voltage.

A unique combination of peak current control and pulse width dimming

management offers simple full-screen brightness control, versatile area

dimming, and a consistent white point. LED string current is set for each

string using a current sense (FET source) resistor. LED current is also digitally

controlled for all eight LED strings. Global string drive pulse width is adjusted

with an 8-bit global intensity register, and individual string pulse width is

modulated with 12-bit control.

The MSL3085 monitors for string open circuit, LED short circuit, loss-of-sync

and over temperature faults, and provides a hardware fault output to notify the

MCU. Detailed fault status and control are available through the serial interface.

Additionally, the MSL3085 includes an on-chip EEPROM that allows the

power-up default register settings to be customized via the serial interface.

The MSL3085 is offered in a 6 x 6 x 0.75mm, 40-pin TQFN package, and

operates over a -40°C to +105°C temperature range.

Applications

Long Life, Efficient LED Backlighting for:

Channel Signs

Architectural Lighting

Ordering Information

EIGHT-CHANNEL LED STRING DRIVER

PART

INTERFACE

PACKAGE

MSL3085BT

40-pin, 6 x 6 x 0.75mm TQFN