DC bus converter chip set

International Rectifier has unveiled the first group of products in the family of DC bus converter chip sets for 48 V input and 150 W board-mounted power converters used in telecom and networking systems.

The architecture establishes benchmarks for efficiency, power density and simplicity, delivering more than 96% efficiency at 20 A/150 Wout. The chip set enables a 53% size reduction when compared with quarter-brick form factors and cuts component count in isolated converters from about 50 components to 20.

The set consists of a single IR2085S control IC and one pair each IRF7493 primary- and IRF6603 secondary-side HEXFET power MOSFETs, plus the IRF7380 for primary-side bias and an IRF9956 for the secondary-side gate clamp.

The chip set is designed for the isolated front-end of two-stage distributed power architectures with an intermediate bus voltage feeding non-isolated point-of-load converters.

Two-stage DPA schemes do not require a tightly regulated intermediate bus voltage, since the point of load will typically accept a relatively wide input voltage and the POL provides the needed regulation to the load. In addition, multiple DC chip sets can be placed in parallel for higher power requirements.