Flexible, Scalable Architecture Backs Converter Chip Set

XPhase is a flexible and scalable architecture for multiphase, interleaved buck dc-dc converters requiring one or more phases. The first XPhase chip set consists of the IR3081 Control IC and the IR3086 Phase IC. It provides a high-performance solution that exceeds the VRM or VRD/EVRD 10.1 requirements for the most advanced microprocessors used in servers and high-end desktop computers. Unlike other multiphase solutions, which are limited in the number of phases they drive, the XPhase architecture enables a scalable multiphase design that accommodates the constant change of advanced CPU power requirements. Packaged in a 28-lead MLPQ, the IR3081 Control IC contains all one-per-converter circuitry, including voltage identification (VID) pull-up resistors, a pulse-width modulation (PWM) ramp oscillator, an error amplifier, bias voltage, fault detection, and other necessary functions. Packaged in a 20-lead MLPQ, the IR3086 Phase IC drives and monitors a single phase in a multiphase converter. It includes all one-per-phase circuitry that includes gate drivers, a PWM comparator and latch, overvoltage protection, current sensing and sharing, and programmable overtemperature detection. The IR3081 Control IC and the IR3086 Phase IC cost $1.65 and $1.25 each, respectively, in 10,000-unit quantities.