IEC 61000-4-5 for PoE applications
The first integrated device providing surge protection
Save 55% of the space occupied by existing protection circuits


June 29, 2009 -- Power over Ethernet (PoE), or IEEE 802.3at, is an industry standard that enables power supply over a network for devices such as VoIP (Voice-over-IP) terminals, wireless LAN access points, RFID tag readers, sensors, and cameras without the need to connect them to a nearby power outlet.

This technology not only improves end-user convenience and flexibility but also allows for lower equipment costs by eliminating the need for external AC/DC power adapters. In 2008, VDC Research Group projected that annual shipments of PoE-enabled Ethernet switches would increase to over 132 million ports by 2012.

STMicroelectronics (www.st.com, Country Manager for Korea Sung-keun Kang), a global leader in protection ICs, has enabled the simplification of the design of equipment powered by Ethernet networks by releasing an integrated surge protection IC that meets Power-over-Ethernet standards and prevents high-voltage surges such as ESD (electrostatic discharge).

ST's PEP01-5841 protection IC can be used in Power Sourcing Equipment (PSE), such as a PoE-enabled Ethernet switch or hub, to drive a specified 48V power supply through an Ethernet cable.

The PoE power circuit of an Ethernet hub or switch can withstand transients on a power line up to 100V. Additional protection is required to prevent very high voltage surges, such as ESD or EOS, from damaging the power supply.

Discrete components are primarily used to clamp surges to voltages below 121V (when specified), and the PEP01-5841 integrates a 100V clamping protection device and a filtering capacitor for up to four PoE outputs in a single 5mm x 6mm component.

This simplifies the design and saves up to 55% of PCB (printed circuit board) space. In addition, PEP01-5841 provides 1kV surge protection as specified in IEC 61000-4-5.