LT3496 Dual Full Function White LED Driver with Integrated Schottky Diodes

The LT3497 is a dual full function step-up DC/DC converter speciﬁ cally designed to drive up to 12 white LEDs (6 white LEDs in series per converter) from a Li-Ion cell. Series connection of the LEDs provides identical LED currents resulting in uniform brightness and eliminating the need for ballast resistors and expensive factory calibration.

The two independent converters are capable of driving asymmetric LED strings. Accurate LED dimming and shutdown of the two LED strings can also be controlled independently. The LT3497 features a unique high side LED current sense that enables the part to function as a “one wire current source;” one side of the LED string can be returned to ground anywhere, allowing a simpler 1-wire LED connection. Traditional LED drivers use a grounded resistor to sense LED current, requiring a 2-wire connection to the LED string.

The 2.3MHz switching frequency allows the use of tiny inductors and capacitors. Few external components are needed for the dual white LED Driver: open-LED protection and the Schottky diodes are all contained inside the 3mm × 2mm DFN package. With such a high level of integration, the LT3497 provides a high efficiency dual white LED driver solution in the smallest of spaces

产品特点 Features

Drives Up to 12 White LEDs (6 in Series per Converter) from a 3V Supply
Two Independent Boost Converters Capable of Driving Asymmetric LED Strings
Independent Dimming and Shutdown Control of the Two LED Strings
High Side Sense Allows “One Wire Current Source” per Converter
Internal Schottky Diodes
Open LED Protection (32V)
2.3MHz Switching Frequency
±5% Reference Accuracy
VIN Range: 2.5V to 10V
Dual Wide 250:1 True Color PWMTM Dimming
Requires Only 1µF Output Capacitor per Converter
Available in a 3mm × 2mm 10-Pin DFN Package

参数

应用

Cellular Phones
PDAs, Handheld Computers
Digital Cameras
MP3 Players
GPS Receivers

典型应用图

LT3496 订购信息和价格参考Package Variations and Pricing

器件型号	封装	引脚	温度	价格 (以 1 ~ 99 片为批量)	价格 (以 1000 片为批量) *
LT3497EDDB#PBF	DFN	10	E	$2.43
LT3497EDDB#TRMPBF	DFN	10	E	$2.43	$1.75
LT3497EDDB#TRPBF	DFN	10	E	$2.43	$1.70

LT3496 数据手册及相关资料下载

数据手册(英文) : LT3497 - Dual Full Function White LED Driver with Integrated Schottky Diodes.PDF
设计要点 (中文) : DN388 - 宽输入范围 1A LED 驱动器利用汽车和 12VAC 电源给高亮度 LED 供电.PDF
设计要点 (中文) : DN449 - 采用 4mm x 5mm QFN 封装的三通道 LED 驱动器能在降压、升压或降压-升压模式中支持 LCD 背光源并提供 3000:1 的 PWM 调光比.PDF
可靠性数据 : R518 Reliability Data .PDF