International Rectifier announced the introduction of the IRFH4251D and IRFH4253D, the first of a family of innovative power block devices for DC-DC synchronous buck applications including advanced telecom and netcom equipment, servers, graphic cards, desktop, Ultrabook and notebook computers.

The 25V IRFH4251D and IRFH4253D feature IR’s latest generation silicon in a novel package that delivers benchmark power density in a 5x6 mm PQFN. The new power block devices feature an integrated monolithic FETKY, and innovative package employing a leading-edge flipped-die technology that enables efficient dissipation of the heat from the source of the synchronous MOSFET directly to the ground layers of the PCB. As a result of improved thermal performance and increased power density, one of the new 5x6 dual devices may replace two 5x6 standard single devices. The new package also utilizes IR’s proprietary single copper clip already employed in PowIRStage and SupIRBuckproducts, as well as an optimized layout that significantly reduces stray inductance to lower peak ringing. This allows the designer the option to use 25V MOSFETs in place of less efficient 30V devices.

Optimized for 5V gate drive applications, the IRFH4251D and IRFH4253D work with any controller or driver to offer design flexibility while delivering higher current, efficiency and frequency capability in a small footprint compared to alternative approaches using two discrete 30V power MOSFETs.



Part Number


Current Rating


PQFN 5 X 6



PQFN 5 X 6


A datasheet is available on the International Rectifier website at

Availability and pricing

Pricing for the IRFH4253D and IRFH4251D begins at US $0.89 and US $1.29 respectively in 10,000-unit quantities. Production orders are available immediately. Prices are subject to change.