Linear Technology Corp. (LTC, Milpitas, CA) announced the new LTC3732 three-phase, five-bit VID, 600kHz, synchronous step-down, switching regulator that drives n-channel, external-power MOSFET stages in a phase-lockable, fixed-frequency architecture. The three-phase controller drives its output stages with 120 degrees of phase separation at frequencies of up to 600kHz per phase to minimize the RMS current dissipated by the ESR of both the input and output filter capacitors.
The LTC3732 utilizes a true current-mode architecture to provide output currents of up to 60A while maintaining current balancing between the three output power stages to within ±5 percent. To optimize efficiencies at light loads, the LTC3732 switches between output stage shedding and Burst-Mode® operation. A differential amplifier provides true remote sensing of both the high and low side of the output voltage at load points enabling ±1 percent output-voltage accuracy. Soft-start and a defeatable, timed, short-circuit shutdown protect the MOSFETs and the load, while a foldback current-limit circuit provides protection during short-circuit or overload conditions.
The LTC3732 is housed in a low-profile, 36-pin, SSOP package and is characterized over the commercial temperature range of 0 to 70 degrees C. Pricing starts at $4.35 each in 1,000-piece quantities.
