International Rectifier has introduced a 30 V synchronous buck converter chipset comprising an IRF6631 control MOSFET and an IRF6638 synchronous MOSFET. The pair features IR's benchmark DirectFET packaging with double-sided cooling and HEXFET MOSFET technology to enable higher levels of efficiency and thermal performance at intermediate current levels, below 18 amperes. Applications include telecommunications, data communications and general-purpose synchronous buck designs — or wherever small size, high efficiency and improved thermal conduction can bring about an increase in power density.

This DirectFET chipset is well suited for designs that require compact and efficient switching in mid-range, 15-ampere to 18-ampere power converter applications. In addition to improving efficiency by more than1% in the 5-ampere to 8-ampere range, savings in board space of 50% can be achieved, compared to traditional approaches that would use three SO-8 devices.

Each device is tailored to maximize performance in its role within a synchronous dc-dc buck converter circuit. The IRF6631 DirectFET control MOSFET reduces switching losses, while the IRF6638 DirectFET synchronous MOSFET lessens conduction losses and reverse-recovery charge.

The IRF6631 control FET features a gate charge of 12 nanocoulombs and delivers a 16% reduction in figure-of-merit of ON resistance gate charge (99.6 milliOhm-nanocoulombs) compared to previous offerings. The IRF6638 synchronous FET delivers a typical ON resistance of 3 milliOhms at 4.5 V, which is a 12% reduction over existing devices, while maintaining the same gate charge.

Both the IRF6631 and IRF6638 DirectFET MOSFETs are available; pricing is $1.05 each for the IRF6631 and $0.65 each for the IRF6638, in 10,000-unit quantities. Both devices are RoHS compliant.

RSS    Save to Del.icio.us  Digg This