LT3478EFE#PBF

LINEAR TECHNOLOGY  LT3478EFE#PBF  发光二极管驱动器, 1输出, 升压, 降压, 降压-升压, 2.8V-36V输入, 2.25MHz开关, TSSOP-16

The is a monolithic step-up DC/DC Converter designed to drive LEDs with a constant current over a wide programmable range. Series connection of the LEDs provides identical LED currents for uniform brightness without the need for ballast resistors and expensive factory calibration. The LT3478 uses an external sense resistor to extend the maximum programmable LED current beyond 1A and also to achieve greater accuracy when programming low LED currents. Operating frequency can be set with an external resistor from 200kHz up to 2.25MHz. Unique circuitry allows a PWM dimming range up to 3000:1 while maintaining constant LED colour. The LT3478 is ideal for high power LED driver applications. One of two CTRL pins can be used to program maximum LED current. The other CTRL pin can be used to program a reduction in maximum LED current vs. temperature to maximize LED usage and improve reliability.

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Integrated resistors for inductor and LED current sensing

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Program LED current de-rating vs. temperature

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Separate inductor supply input

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Inrush current protection

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Programmable soft-start

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Open LED protection

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Accurate shutdown/UVLO threshold with programmable hysteresis