Dual sync step-down DC-DC controller with digital power system management

Linear Technology has introduced the LTC3887, a new dual-output synchronous step-down DC-DC controller with I²C-based PMBus interface for digital power system management. The LTC3887 differs from the previously released LTC3880 with an enhanced feature set that includes a faster 70ms power-up time, higher output voltage capability and a fast ADC mode that provides an 8ms update rate for one parameter. In addition, the LTC3887 and LTC3880 have a common board footprint. The LTC3887 combines best in class analog switching regulator performance with precision mixed signal data conversion for unsurpassed ease of power system design and management, supported by the LTpowerPlay software development system with easy-to-use graphical user interface (GUI). The LTC3887 enables digital programming and read back for real-time control and monitoring of critical point-of-load converter functions. Programmable control parameters include output voltage, margining and current limits, input and output supervisory limits, power-up sequencing and tracking, switching frequency, and identification and traceability data. On-chip precision data converters and EEPROM allow for the capture and nonvolatile storage of regulator configuration settings and telemetry variables, including input and output voltages and currents, duty cycle, temperature and fault logging. The LTC3887 can regulate two independent outputs or can be configured for a two phase single output. Up to 6 phases can be interleaved and paralleled for accurate sharing among multiple ICs, minimizing input and output filtering requirements for high current and/or multiple output applications. An integrated amplifier provides true differential remote output voltage sensing, enabling high accuracy regulation, independent of board IR voltage drops. Applications include high current ASIC, FPGA and processor supplies in telecom, datacom, computing and storage markets.