New Industry Products

IR Releases XPhase® Chipset For AMD® & VID Processors

February 17, 2008 by Jeff Shepard

International Rectifier (IR)® introduced the IR3514 and IR3507 XPhase® chipset for AMD® parallel and serial VID (PVID and SVID) processors.

The IR3514 control IC enables designers to migrate from AMD processors requiring a parallel VID to SVID processors without the need to change the motherboard. Combined with the IR3507 phase IC, the IR3514 provides Power Saving Interface (PSI) capability to turn phases(N-1) on or off depending on CPU load requirements. The IR3514 is designed to receive power savings commands through the SVI serial bus and communicates this information to the IR3507 phase IC to improve efficiency at light loads and MIPS per watt.

"This new XPhase chipset, co-designed with the latest generation of IR’s DirectFET® MOSFETs, offers a power supply that is smaller and easier to design while providing higher efficiency and a lower overall system cost than conventional approaches, delivering a full-featured and flexible approach to implementing a complete CPU power solution," said Jeff Sherman, IR’s Senior Marketing Manager for Enterprise Power Products.

Housed in what is said to be a 25% smaller package than a traditional six-phase control IC, the IR3514’s six-wire communication bus is said to simplify routing, and, by reducing the number of external discrete components required, to significantly reduce board space. The IR3514 interfaces with any number of phase ICs each driving and monitoring a single phase. The IR3514 provides independent control of both the VDD core and VDDNB auxiliary planes required by next-generation AMD CPUs when operated in SVI mode.

When operated in PVI mode, the IR3514 controls the VDD core plane through six parallel VID input bits while the VDDNB plane power stage is kept at high impedance. An overall system set point accuracy of 0.5% is achieved. Other features include programmable dynamic VID slew rates, programmable VID Offset (VDD output only) and programmable output impedance (VDD output only).

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 is said to simplify PCB layout and provides a more robust design.

Pricing for the devices begins at US$1.75 each in 10,000-unit quantities for the IR3507MTRPBF and US$2.45 each in 10,000-unit quantities for the IR3514MTRPBF. Pricing for the IRF6712STRPBF, IRF6714MTRPBF and IRF6715MTRPBF begins at US$0.39, US$0.71 and US$0.80 each in 10,000-unit quantities respectively. The devices are RoHS compliant.