The LT3755EUD#PBF is a DC/DC Controller designed to operate as a constant-current source for driving high current LEDs. It drives a low-side external N-channel power MOSFET from an internal regulated 7.15V supply. The fixed frequency, current mode architecture results in stable operation over a wide range of supply and output voltages. A ground referenced voltage FB 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 controller sense output current at the high-side of the LED string. High-side current sensing is the most flexible scheme for driving LEDs, allowing boost, buck mode or buck-boost mode configuration. The PWM input provides LED dimming ratios of up to 3000:1 and the CTRL input provides additional analogue dimming capability.
Constant-current and constant-voltage regulation
Open LED protection
Programmable under-voltage lockout with hysteresis
(EN)
