The BMR457 Advanced Bus Converter (ABC) from Ericsson is the second model in its 32-bit processor-based FRIDA II 3E digital Advanced Bus Converter family. Following the launch last month of its quarter-brick sibling, the BMR456, the new eighth-brick-format BMR457 delivers unprecedented performance to system architects developing equipment for ICT (Information and Communication Technology) applications that require a small footprint, fast response time, tightly regulated intermediate bus voltages and high efficiency at any point of operation to reduce power consumption.
Like the BMR456, the BMR457 includes a 32-bit ARM-based digital microcontroller that embeds the advanced 'Ericsson DC/DC Energy Optimizer' firmware. This has been developed by Ericsson to guarantee the highest performance at any point of operation from low to high load, which is commonplace when handling data traffic. The 'Ericsson DC/DC Energy Optimizer' firmware combines advanced Ericsson Intellectual Property (IP) together with a series of functions to continually optimize switching parameters and reduce energy consumption to an absolute minimum.
The BMR457 is available in two input voltage ranges: from 36V to 75V, delivering an output power of 264W; and 40V to 60V, delivering 300W. Output voltage can be adjusted in a range of 6.9V to 13.2V via PMBus commands, making BMR457 suitable for Dynamic Bus Voltage operation with its ability to reduce energy consumption when traffic data demand is low.
The Ericsson DC/DC Energy Optimizer handles input voltage transients with slew-rates of up to 0.5V/µs, while keeping the output voltage within ±10% and ensuring that the output voltage does not trigger over-voltage protection. It also offers the highly efficient management of pre-bias start-up operation and a fully controlled shutdown process, avoiding voltage spikes that could cause an avalanche condition in the secondary-side synchronous rectification MOSFET, thereby contributing to improved reliability.
Designed to be fully integrated and optimized in the energy chain, the BMR457 includes a USER_STORE memory block, which can be used by system designers to store their own customized configuration files to profile BMR457 behavior to match certain conditions. This level of functionality, combined with PMBus control, offers a very high degree of flexibility to deliver the appropriate amount of energy when required by the load, avoiding unnecessary power losses.
The BMR457 offers a typical efficiency of 95.2% and flat curve behavior from 20% to 100% load: this makes the product the most efficient wide-operational-range Advanced Bus Converter in its category. This high level of performance is a result of the combination of the Ericsson DC/DC Energy Optimizer firmware and the new highly optimized powertrain and embedded transformer layout of the FRIDA II platform. This provides end users with a fully regulated output voltage across the overall operation range from 36V to 75V and without 'grey zones' below 40V. This industry-first combination guarantees that systems architects will always obtain the power their application requires without having to be concerned about unregulated behavior.
Designed for flexibility and high-power applications, when connected in parallel the Droop Load Sharing (DLS) version of the BMR457 telecom (36V to 75V) and datacom (40V to 60V) versions can deliver 522W and 592W, respectively.
The BMR456 meets the insulation requirements of EN60950, sustains an I/O isolation voltage of 2250 VDC, and also offers an extensive set of capabilities and features such as: remote sensing; PMBus-configurable protection (over-temperature, over-current and over-voltage); configurable start/stop; precision delay ramp-up; voltage margining; configurable fault response; power good; and extensive power management programmability.
Additionally, to assist in the design process, a system development board - called the ROA1283835 - is available, offering designers the ability to connect to other Ericsson 3E development boards that host digitally controlled 3E Point-of-Load (POL) converters and to create a complete solution prior to implementation in the final application.
The price of the BMR457 starts at $40 in OEM quantities. The ROA1283835 stand-alone development board is priced at $200.