特点
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
典型应用
典型应用
描述
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.