The LTC3733 family are PolyPhase synchronous stepdown switching regulator controllers that drive all N-channel external power MOSFET stages in a phaselockable, fixed frequency architecture. The 3-phase controller drives its output stages with 120 phase separation at frequencies of up to 530kHz per phase to minimize the RMS current dissipated by the ESR of both the input and output filter capacitors. The 3-phase technique effectively triples the fundamental frequency, improving transient response while operating each phase at an optimal frequency for efficiency and ease of thermal design. Light load efficiency is optimized by using a choice of output stage shedding or Burst Mode technology.