LT3955EUHE#PBF

LINEAR TECHNOLOGY  LT3955EUHE#PBF  发光二极管驱动器, 1输出, 升压, 降压, 反激, SEPIC, 4.5V-60V输入, 1MHz开关, QFN-36

The is a DC/DC Converter designed to operate as a constant-current source and constant-voltage regulator. It features an internal low-side N-channel MOSFET rated for 80V/3.5A. The LT3955 is ideally suited for driving high current LEDs, but also has features to make it suitable for charging batteries and super-capacitors. The fixed frequency, current mode architecture results in stable operation over a wide range of supply and output voltages. A voltage feedback pin serves as the input for several LED protection features and also makes it possible for the converter to operate as a constant-voltage source. A frequency adjust pin allows the user to program the frequency from 100kHz to 1MHz to optimize efficiency, performance or external component size. The PWM input can be configured to self-oscillate at fixed frequency with duty ratio programmable from 4 to 96%. When driven by an external signal, the PWM input provides LED dimming ratios of up to 3000:1.

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Programmable PWM dimming signal generator

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Constant current ±3% and constant-voltage ±2% regulation

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Accurate analogue dimming

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Output short-circuit protected boost

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Open LED protection and reporting

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Programmable VIN UVLO with hysteresis

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C/10 Indication for battery chargers

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0 to 80V Rail-to-rail current sense range