Three- To 12-Phase DC-DC Controller Cranks Out 60-A Distributed Power

The LTC3731 three-phase synchronous step-down switching controller with integrated MOSFET drivers is expandable to 12 phases. This single-IC solution delivers up to 60 A for distributed power in systems requiring dc-dc conversion from a 4.5- to 32-V input source to a 0.6- to 6-V output. It drives n-channel MOSFETs with 120° phase separation. The scalable dc-dc controller lets multiple LTC3731s operate in six, nine, and 12 phases able to deliver load currents as high as 240 A. Its precision ±5% output-current matching simplifies thermal management by spreading the heat evenly among its three output stages. The IC operates from 250 to 600 kHz per phase. Pricing starts at $4.45 each in 1000-unit lots.