New Industry Products

IR Expands XPhase® Family of Scalable Multiphase Converter Chipsets

May 31, 2007 by Jeff Shepard

International Rectifier (IR®) announced that it has expanded the XPhase® family of scalable multiphase converter chipsets with the introduction of the IR3500 Control IC and IR3505 Phase IC. The new XPhase chipset is said to provide a full-featured and flexible way to implement a complete Intel® or AMD® CPU power solution, and with simple six-bit voltage programming, the IR3500 is claimed to be easily configured for use in general purpose, multiphase applications.

The latest XPhase chipset reduces external component count by 25%, which combined with a higher switching frequency, reduces the powertrain area by 45% in a five-phase design compared to previous generation technology. The solution features the IRF6622 and IRF6628 DirectFET® power MOSFETs to achieve a 2% efficiency improvement compared to competing solutions.

"Our new XPhase generation enables a power supply that is smaller and easier to design while achieving higher efficiency," said Jeff Sherman, Senior Marketing Manager of IR’s dc-dc multiphase computing products.

The XPhase chipset features programmable dynamic voltage identification (VID) slew rate, programmable VID offset and load line output impedance, hiccup over-current protection with delay to prevent false triggering, and simplified power good output to indicate correct operation and prevent false triggering.

XPhase is IR’s distributed multiphase architecture that consists of control ICs and phase ICs that communicate using a simple six-wire bus scheme. Phases can be added or removed without changing the fundamental design. The six-wire bus consists of a three-wire digital phase timing bus, an average current, an error amplifier output and a VID voltage. By eliminating point-to-point wiring between the control and the phase ICs, the six-wire bus shortens interconnections, and reduces parasitic inductance and noise. This simplifies PCB layout and provides a more robust design.

All in 10,000 unit quantities, pricing is US$1.95 each for the IR3500MPBF and IR3500MTRPBF, and US$1.65 each for the IR3505MPBF and IR3505MTRPBF. Production orders are available immediately.