Product category:
Discrete Power Devices
News Release from: International Rectifier | Subject: IRF4000
Edited by the Electronicstalk Editorial
Team on 06 February 2006
MOSFETs come together to save space for
PoE
The IRF4000 from International Rectifier is a 100V-rated device integrating four HEXFET MOSFETs into a single power MLP package for power-over-Ethernet applications.
The IRF4000 from International Rectifier is 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 IEEE802.3af 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
This article was originally published on Electronicstalk on 15 Feb 2001 at 8.00am (UK)
Related stories
1kV rad-hard power MOSFET saves satellite space
International Rectifier has introduced the world's first 1000V radiation-hardened power MOSFET.
MOSFETs improve 12V-input converter efficiency
Two new 20V HEXFET power MOSFET families from International Rectifier are designed to increase efficiency by up to 4% in 12V-input DC/DC convertors.
The reduced footprint equates to a space savings of up to 80%, or 19.35cm2 of circuit board area in a typical 48-port board.
As 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.
The IEEE802.3af 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 1C/W package thermal resistance to enable efficient removal of heat while operating in the linear region and has been fully electrically and thermally characterised under worst case IEEE802.3af operating conditions.
The new device guarantees a 56% higher device safe operating area compared with 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.
The IRF4000 is compliant with the upcoming PoE Plus architecture for high power loads in addition to the IEEE802.3af specification.
• International Rectifier: contact details and other news
• Email this article to a colleague
• Register for the free Electronicstalk email newsletter
• Electronicstalk Home Page
Search the Pro-Talk network of sites
