Power Block package: high density, compact DC-DC format

December 16, 2014 // By Graham Prophet
International Rectifier’s IRFH4257D comprises a FastIRFET dual power MOSFET housed in a 4 x 5 mm PQFN power block package. The new package option expands the power block family’s capability to lower power for compact designs in 12V input DC-DC synchronous buck applications.

The IRFH4257D features IR's latest generation silicon and packaging technology for thermal performance, low on-state resistance (RDS(on)) and gate charge (Qg). The IRFH4257D works with any controller or driver to offer flexibility while delivering higher current, efficiency and frequency capability in single phase or multiphase applications. The IRFH4257D provides an option of a 4x5 or 5x6 PQFN to suit design requirements.

Part Number

PQFN Package size

Current rating

Typ. / Max RDSon @ 4.5V

QG typical @ 4.5V (nC)

QGD typical @ 4.5V (nC)




3.7 / 4.6

1.65 / 2.1





International Rectifier; www.irf.com