Digital control optimizes intermediate-bus efficiency

摘要

Back in the 1990s, the need for multiple high-current, sub 5-V power supplies to power the silicon that underpins communications infrastructures drove designers to adopt distributed power architectures (DPA). A classic DPA example uses an ac-dc front end to convert utility power to a distribution rail voltage that supplies a number of isolated dc/dc brick converters, each of which supplies a low-voltage load. This model evolved into the intermediate-bus architecture (IBA) that now dominates, where an isolated dc/dc converter down- converts the distribution rail voltage to an intermediate-bus level; in a second stage of downconversion, nonisolated point-of-load converters supply the voltages that the load circuits require.