Digitally-controlled dc-dc converters design kit simplifies exploration of digital power architectures

June 23, 2011 // By Paul Buckley
Ericsson's 3E range of digitally-controlled dc-dc converters has been expanded to feature two intermediate-bus converters that source up to 240 and 396 W to power a choice of complementary 3E point-of-load regulators that can each supply 12 - 40 A.  A second generation of the design kit, with extended features, now simplifies their implementation within PMBus systems.

The 3E Gold Edition design kit hardware comprises two boards that accommodate one or two intermediate-bus converters and up to six point-of-load regulators. Sample devices include the BMR453 and BMR454 intermediate-bus converters together with examples of the 12 A BMR462, 20 A BMR463, and 40 A BMR464 point-of-load regulators. The boards can operate independently or be plugged together to form a representative PMBus-controlled power system. Users have only to add a suitable power supply and test equipment to create a development environment that can realistically mirror a target application.     

The design kit includes a USB-to-PMBus adapter that provides a seamless interface between the 3E GUI Gold Edition software running on a Windows PC and the target 3E family dc-dc converters. The 3E GUI Gold Edition software package together with an extensive library of technical papers and supporting information that accompanies the hardware elements can be download from Ericsson Power Modules website.     

At power-on, the software scans the PMBus to discover which devices are present. It then continually reads and displays each converter's key operating parameters - its input and output voltages, output current, and on-chip temperature - at intervals that users can specify. The Device Monitor window graphs these details for a selected device as it runs, while the System Monitor window tracks the status of all devices connected to the PMBus. Particularly useful for troubleshooting, the PMBus Transaction Log records and displays time-stamped data exchanges across the bus as the software runs.     

The 3E GUI Gold supports heterogeneous combination of devices fulfill the PMBus Specification rev 1.1 which makes it possible to scan and monitor other PMBus units connected to the system.     

The Basic & Protection Configuration pane allows users to enter an array of values that define how each converter operates using simple graphical controls that simplify device programming. Available parameters include output voltage levels, delay and slew-rate values for power-supply sequencing in multi-rail