25A digital point-of-load regulator embeds dynamic loop compensation

December 12, 2013 // By Graham Prophet
A 25A regulator offers very high power density of 28.44 W/cm3 (465 W/in3) and 25% more output current in the same footprint as second-generation 20A module. Dynamic Loop Compensation improves stability and shortens time-to-market; paralleling of seven modules with phase spreading delivers 175A, while ripple-and-noise is reduced to the lowest possible level

The Ericsson 3E series BMR463-25A is a third-generation digital point-of-load (POL) regulator that features Dynamic Loop Compensation (DLC) and delivers a 25% increase in output current over the second-generation BMR463-20A, yet comes in a fully compatible footprint. The product features a full set of PMBus commands enabling systems architects to fully monitor and dynamically control the energy delivered to strategic components, such as processors, FPGAs, ASICs and others, down to a very low and highly economical level.

Embedding Dynamic Loop Compensation, the BMR463-25A runs the DLC algorithm as default each time the output is enabled. However, three more settings are also available via the PMBus for systems architects to choose the most appropriate method for their application with the DLC algorithm run every second or every minute or simply disabled. In addition to standard methods, designers can also use the Loop Compensation Tool featured in the latest Ericsson Power Designer software to set their own loop compensation profile to match specific application requirements. In addition, developed with high efficiency in mind, the BMR463-25A powertrain is composed of the latest MOSFET technology to deliver up to 95.2% efficiency at 3.3V output and up to 89.4% at 1.0V when the output load is at 50%.

With an input voltage range of 4.5V to 14.0V, the BMR463-25A complies with most intermediate bus voltages (5V to 12V) that are used in the industry and provides an adjustable output voltage from 0.6V to 3.3V with the factory default set at 1.2V. Output voltage can be adjusted through simple PMBus commands or via a 1% tolerance pin-strap resistor offering 28 different levels of output voltages.

When higher power or a ‘star-point current distribution’ is required, the BMR463-25A can be paralleled with up to seven devices delivering a total current of 175A. When in parallel, the modules can be synchronised with the use of phase-spreading reducing noise and peak current. Phase-spreading can be simply simulated and programmed