New digital quarter-brick ABC lowers power consumption

Ericsson's first model in its second-generation digital-ABC (Advanced Bus Converter) product line is based on the company's FRIDA II digitally controlled power platform. The BMR456 3E ABC delivers fast response time, tightly regulates intermediate-bus voltages, and provides high efficiency at any operating point to reduce power consumption for system architects working on telecom and datacom applications. This latest generation of Ericsson DC-DC converters is based on the 32-bit ARM microcontroller. The FRIDA II firmware developed by Ericsson assures high performance from low-load to high-load operation, and the ability to handle line transients, such as those occurring in ATCA (Advanced Telecommunications Computing Architecture) applications when switching feeds. Designed for telecom and datacom applications, the quarter-brick BRM456 comes in two input-voltage ranges: 36 V to 75 V, delivering output power of 420 W; and 40 V to 60 V, delivering output power up to 468 W. Systems can adjust the converter's output voltage from 4.0 V to 13.2 V by means of PMBus commands. This capability makes the BMR456 suitable for dynamic bus voltage operation, which facilitates energy savings when communication traffic is low. The converter's typical efficiency is 96.5%, exhibiting a flat curve from 14% to 100% load. Designed for flexible, high-power applications when connected in parallel, the DLS (droop load sharing) version of the BMR456 telecom (36-75V) and datacom (40-60V) versions deliver 756 W and 842 W, respectively. The BMR456 handles input-voltage transients with slew rates of up to 0.5 V/μs, keeping its output voltage within ±10% to ensure loads do not exceed their over-voltage protection thresholds. Highly efficient management of pre-bias start-up operation and a fully controlled shutdown process avoids avalanche conditions in the secondary-side synchronous rectification MOSFET, and contributes to improved reliability. A USER_STORE memory block for system designers and customized configuration files combined with PMBus control offers high flexibility to meet the load's energy demand, avoiding unnecessary power loss. A new power-train and embedded transformer layout, combined with FRIDA II firmware provides end users with fully regulated output voltage across the overall operation range from 36V to 75V without grey zones below 40 V. The BRM456 is fully backward compatible with Ericsson's previous generation of ABCs. The I/O connector guarantees full alignment and co-planarity in both through-hole and surface-mount soldering processes. For more information, see http://bit.ly/L0PKCJ