LT3476 Datasheet | Linear Technology

Features n True Color PWMTM Dimming Delivers Up to 5000:1 Dimming Ratio (In Boost Configuration) n LED Current Regulation with High-Side Sense n VADJ Pin Accurately Sets LED Current Sense Threshold Over Range 10m V to 120m V n Four Independent Driver Channels with 1.5A, 36V Internal NPN Switches n Frequency Adjust Pin: 200k Hz to 2MHz n High Efficiency Conversion = Up to 96% n Open LED Protection n Low Shutdown Current < 10µA n Wide VIN Range: 2.8V to 16V n Thermally Enhanced, 38-Lead, 5mm × 7mm QFN Package Applications n RGGB Lighting n Automotive and Avionic Lighting n TFT LCD Backlighting n Constant-Current Sources LT3476 High Current Quad Output LED Driver Description The LT®3476 is a quad output DC/DC converter designed to operate as a constant-current source for driving high current LEDs. A fixed frequency, current mode architecture results in stable operation over a wide range of supply and output voltages. A frequency adjust pin allows the user to program switching frequency between 200k Hz and 2MHz to optimize efficiency and external ponent size. The LT3476 senses output current at the high side of the LED. High side current sensing is the most flexible scheme for driving LEDs, allowing buck, boost or buckboost configurations. Each current monitor threshold is trimmed to within 2.5% at the full scale of 105m V. With an external sense resistor, the user programs the output current range of each channel. Each of the four regulators is independently operated by that channel’s PWM signal. This PWM feature allows precise adjustment of the color mixing or dimming ratio of the LED source. Dimming ratios up to 1000:1 can be achieved. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and True Color PWM is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Typical Application 100W Quad 1A × 8 LED Driver PVIN 33V CAP1 100mΩ LED1 CAP2 100mΩ LED2 CAP3...