Dual 3A buck in a 4x5 QFN — what the package tells you
The LTC3633IUFD#PBF is a dual-channel synchronous step-down regulator delivering 3 A per output from a 3.6 V to 15 V input rail. The tube packaging means it arrives in a stick, not on a reel; if your pick-and-place line expects tape, budget a tube-to-tape transfer step or order the tape-and-reel suffix variant.
Switching frequency and output flexibility
Switching frequency is programmable from 500 kHz to 4 MHz via a resistor or external sync — a 2 MHz setting shrinks the inductor to 1 µH or so, which keeps the total solution footprint tight around the QFN. The two outputs share the same frequency but regulate independently, each adjustable from 0.6 V up to 14.7 V (14.7 V is the input ceiling minus a dropout headroom).
Thermal envelope and rework considerations
Pin 1 is marked by a chamfer on the package corner — check the orientation before placing, because a QFN rotated 90° lands the supply pins on the wrong pads and the magic smoke escapes.