Conversion chip set

International Rectifier has introduced a control and synchronous switching chip set for high-frequency DC-DC converters powering next-generation Intel and AMD processors.

Other applications include point-of-load DC-DC conversion in telecom and datacom systems.

The chip set pair delivers 84.5% efficiency at 90 A in a four-phase 1U VRM outline system switching at 750 kHz per phase and 87% efficiency at 150 A in an eight-phase embedded VRD10.2 design switching at 400 kHz per phase.

The first device is the monolithic IRF6691 DirectFETKY, which integrates a Schottky diode and synchronous MOSFET into a single package to enable an efficiency improvement of 1.1% at 1 MHz per phase at full load compared with other existing highest-performing 20 V synchronous FETs on the market when using the same control FET.

The device also features a typical RDS(on) of 1.2 mOhm at 10 VGS (1.8 mOhm at 4.5 VGS).

The second device is the IRF6617 DirectFET HEXFET control MOSFET. Specifically tailored for controlling FET switching, the device features a low total gate charge (Qg of 11 nC), delivering a 33% reduction in on-resistance times gate charge product of 87 mOhm-nC at 4.5 VGS compared to previous 30 V devices.