PoE: The Power Oriented Era

Power over Ethernet (PoE) is a technology that provides both electric power and data connection over a twisted pair Ethernet cable. It was standardized by the IEEE in 2003 (IEEE 802.3af). Even though this technology has been around for over 15 years, often design engineers are unsure about how Ethernet magnetics for PoE applications are designed. Some factors need to be taken into account during design stage: RDC losses, temperature rise, saturation… Würth Elektronik eiSos GmbH & Co. KG manufactures and provides Ethernet magnetics since over a decade, including PoE components. It has made huge improvements on this topic and designs and produces Ethernet magnetics that can handle up to 2 A of PoE current. In this presentation, an overview of the latest PoE standards, its applications and development of PoE components will be given. Furthermore, some measurements of PoE Ethernet magnetics will be shown.