A 420W, PMBus compliant DC/DC converter in 1/4-brick format

June 23, 2014 // By Graham Prophet
Murata's DBQ series of isolated digitally controlled DC-DC converters incorporates a 32-bit ARM7 processor: the 420W regulated DBQ0135V2 model is the first in a series of DC-DC converters to include a PMBus-compatible digital interface.

The DBQ series is packaged in a standard quarter-brick format incorporating the Advanced Bus Converter (ABC) pinout for PMBus communications to an isolated DC-DC converter.

DBQ0135V2 is an isolated, regulated, 420W-12V-out quarter-brick that supports the TNV input voltage range of 36V-75V with a typical efficiency of 95.2%. To achieve this level of performance, the DBQ uses a 32-bit ARM7 processor and proprietary firmware to control all critical functions of the module. The module provides a digital interface supporting the PMBus standard for digital power management in systems used in applications such as MicroTCA, servers, storage, networking equipment, PoE wireless networks, and industrial and test equipment.

The PMBus interface provides power management features not previously available in an isolated, modular, 1/4 brick DC-DC converter, Murata claims. By interfacing the DBQ to the system's I2C bus, a systems engineer can monitor critical system level performance requirements that include Vin, Iin, Vout, Iout, and operating temperature. The PMBus can also be used to set warning flags for temperature, Vin, Vout, and Iout, and allows the user to customise parameters such as Vout, Vin turn on/off thresholds, output over voltage protection, output current limit, and ramp-up characteristics.

The DBQ series “droop” load sharing option allows three modules to be connected together in parallel for added power or to provide redundancy in high-reliability applications. The converter also offers input to output isolation of 2250 VDC as required for Power over Ethernet (PoE) applications.

A GUI (Graphical User Interface) and evaluation boards are available to assist the power engineer in designing a state-of-the-art power system.

Murata Europe; www.murata.eu