The LTC3883/LTC3883-1 are PolyPhase capable DC/DC synchronous step-down switching regulator controllers with a PMBus compliant serial interface. The controllers use a constant frequency, current mode architecture that is supported by the LTPowerPlay software development tool with GUI. Switching frequency, output voltage, and device address can be programmed using external configuration resistors. Additionally, parameters can be set via the digital interface or stored in on-chip EEPROM. The LTC3883/LTC3883-1 can be configured for Burst Mode operation, discontinuous mode or continuous inductor current mode. The LTC3883 incorporates an internal 5V linear regulator while the LTC3883-1 uses an external 5V supply for minimum power loss.