Chipset shrinks powertrain footprint by 45%

International Rectifier has expanded its XPhase family of scalable multiphase converter chipsets with the introduction of the IR3500 control IC and IR3505 phase IC. The new XPhase chipset provides a full-featured and flexible way to implement a complete Intel or AMD CPU power solution. Boasting simple 6bit voltage programming, IR3500 is easily configured for use in general purpose, multiphase applications.

The latest XPhase chipset reduces external component count by 25 percent, which combined with a higher switching frequency, reduces powertrain area by 45 percent in a five-phase design compared to previous-generation technology. The solution features the IRF6622 and IRF6628 DirectFET power MOSFETs to achieve a two percent efficiency improvement compared to competing solutions. The new XPhase generation enables a power supply that is smaller and easier to design while achieving higher efficiency, said the company.

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. IT also has 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.