What this controller does — and what it doesn't
The LT3755EMSE-1#PBF is a DC/DC controller designed specifically for driving LEDs. It is not a converter with an integrated switch — the external MOSFET is your call, which gives flexibility in current rating and thermal layout. The controller supports four topologies: buck, boost, SEPIC, and flyback, so it can handle a string of LEDs whether the input is above, below, or equal to the output voltage. Dimming is handled either by analog control or PWM. The input supply range runs from 4.5 V to 40 V, covering automotive battery rails and industrial supplies.
Package and thermal — the exposed pad matters
The part comes in a 16-lead MSOP with an exposed pad (16-MSOP-EP).