EL SEGUNDO, Calif. — December 2005 — International Rectifier, IR® (NYSE: IRF), a world leader in power management technology, today introduced the IRF4000, a 100V-rated device integrating four HEXFET® MOSFETs into a single Power MLP package for Power-over-Ethernet (PoE) applications. The new device complies to the IEEE 802.3af specification for networking and communications infrastructure systems, such as Ethernet switches, routers and hubs, delivering up to 15W per port, replacing four individual SOT-223-packaged MOSFETs. The reduced footprint equates to a space savings of up to 80%, or three square inches of circuit board area in a typical 48-port board.

“Considering that each port in a PoE card requires its own MOSFET, the IRF4000 significantly reduces part count over the alternative of using individual MOSFETs in the same circuit. Manufacturing can also be simplified, eliminating 36 component insertions in a 48-port system,” said Carl Smith, marketing manager for networking and telecommunication products at International Rectifier.

The IEEE 802.3af specification outlines power delivery requirements from the power sourcing equipment (PSE) through the LAN cable to the powered device (PD) in a networking system. The MOSFET operates like a hot-swap FET, transferring power from the PSE to the PD in a controlled fashion, and must operate in the linear region through a demanding worst-case operating condition therefore requiring an extremely robust safe operating area (SOA).

The low transconductance silicon technology used in the IRF4000 combines with about 1°C/W package thermal resistance to enable efficient removal of heat while operating in the linear region and has been fully electrically and thermally characterized under worst case IEEE 802.3af operating conditions. The new device guarantees a 56% higher device safe operating area compared to individual SOT-223 MOSFETs, improving system reliability and thermal margin.

In addition to 48-port systems, the IRF4000 is ideal for 96-port applications or for smaller PoE “jack companion” modules using 12-ports where, in each case, four ports can be addressed with a single IRF4000 device. The new device is qualified to industrial moisture sensitivity level (MSL) 3.

In addition to the IEEE 802.3af specification, the IRF4000 is compliant with the upcoming PoE Plus architecture for high power loads.

Part Number	Package	VDSS	RDS(on) max 12Vgs	RDS(on) max 10Vgs	Idss @ 100V	Rthj-lead
IRF4000	10mm(l) x 5mm(w) x 1.85mm (h) Power MLP	100V	270mOhm @ 12Vgs	350mOhm @ 10Vgs	1.5uA max	1.5°C/W max

Availability and Pricing

The new IRF4000 is available now. Pricing is US $2.00 each in 10,000-unit quantity. Prices are subject to change.