Higher power over Ethernet: First powered device controller

First Powered Device (PD) Controller implementing the 2-Event Physical Layer Classification of IEEE 802.3at standard (Draft 2.0); upcoming PoE standard raises available PD input power to 30 W from 13 W in the existing 802.3af standard, says Akros Silicon.

By Control Engineering Staff March 25, 2008

Folsom, CA

Akros Silicon Inc

. announced the industry’s first Powered Device (PD) Controller, implementing the 2-Event Physical Layer Classification of IEEE 802.3at standard (Draft 2.0). The upcoming PoE standard raises available PD input power to 30 W from the previous level of 13 W in the existing 802.3af standard. The power level opens up applications for PoE, including IP security cameras with power, tilt and zoom (PTZ) capability, multi-radio 802.11n wireless access points, WiMax customer premise equipment, SOHO Ethernet switches, thin clients, and LCD displays.
2-Event Classification allows the PD to recognize whether it is connected to Type 1 (802.3af/13W) or Type 2 (802.3at/30W) power sourcing equipment (PSE), and vice-versa. The 2-Event Classification informs the IEEE 802.3at-compliant PSE that it is safe to increase power from 13 W to 30 W. Use of the protocol between Type 2 PSE and Type 2 PD permits dynamic negotiation and allocation of power, leading to more efficient system power management.
The company has completed testing the interoperability of the

AS1135 PD controller

with Microsemi’s PD64001 PSE Power Manager, in accordance with the IEEE 802.3at-Draft2.0 standard, which allows users to implement both ends of the PoE link. AS1135, an extension of the AS1100 family, supports new features in the same small package. The part provides AT Detect functionality on a logic output pin, indicating successful PoE connection to Type 2 PSE. The hardware feature can be used by the system microcontroller to self-configure the networked appliance based on the power delivery capability of the network. AS1135 can operate with local power input as low as 10 V.
“While many silicon vendors have been developing and announcing controllers suitable for high power applications for some time, as the first to include support for 2 Event Classification in its PD Controller, Akros Silicon has demonstrated its commitment to this growing market,” said VDC senior analyst Brian Greenberg.
“There are many instances where it is beneficial to provide Ethernet appliances that can operate from the power supplied by either the PoE line or a local power source,” said Amit Gattani, director of marketing, Akros Silicon. “For instance, manufacturers of IP cameras may want to provide the local power option to allow their product to be used in a network that has not yet been upgraded to PoE. This feature allows system designers to benefit from the use of commonly available, low-cost 12 V power adapters for auxiliary power.”

Another product from Akros: Ethernet development: Less debug with noise suppression, ESD protection


Need some history? Take a look at Power over Ethernet specification approved : IEEE 802.3af gives hope to device-level Ethernet.

Control Engineering News Desk
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