The 2-Event Classification allows the PD to recognize whether it is connected to a 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 delivered to the PD from 13W to 30W. Use of this classification protocol between Type 2 PSE and Type 2 PD enables dynamic negotiation and allocation of power, leading to more efficient system power management.
“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 Brian Greenberg, senior analyst at VDC, who tracks the PoE and Power Management markets.
Akros Silicon has also successfully completed testing the interoperability of the new AS1135 PD Controller with Microsemi’s recently released PD64001 PSE Power Manager, in accordance with the IEEE® 802.3at-Draft2.0 standard – an important milestone for the industry, as it allows customers to effortlessly implement both ends of the PoE link (both PSE and PD).
The AS1135 controller is an extension of Akros’ highly successful and field-proven AS1100 family, supporting many new features in the same small 5x5 20pin QFN package. The part provides “AT Detect” functionality on a logic output pin, indicating successful PoE connection to Type 2 PSE. This hardware feature can be used by the system micro-controller to self-configure the networked appliance based on the power delivery capability of the network. The AS1135 is also capable of operating with local power input as low as 10V.
“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 12V power adapters for auxiliary power.”
Another new feature is the capability to externally set the switching frequency of the integrated DC-DC controller in the 100kHz - 500kHz range. This gives designers added flexibility to optimize the system for parameters like EMI, power consumption and component sizes. Lower switching frequencies can be beneficial in controlling EMI and improving no-load efficiency. Designers may also use higher switching frequencies to reduce the size of components used in the power converter output stage. These features are additions to standard features found in the AS1100 product family like integrated surge protection and low emissions DC-DC controller, to enable EMC ready system designs.
Pricing and Availability
Akros offers reference designs and evaluation boards to help evaluate the performance of the AS1135. The AS1135 is available in a 20-pin 5x5 QFN with a Reduction of Hazardous Substance (RoHS) compliant package. The device is priced at $1.66 for 1kU quantity. To find a local manufacturing representative and order samples, visit http://www.AkrosSilicon.com.
Summary of Features
The AS1135 is fully integrated and designed to provide the following features at a system level:
Full support of the IEEE® Std. 802.3af-2005 and pre-standard IEEE® Std. 802.3at (Draft 2.0) power requirements
Support of the 2-event Physical Layer Classification (per 802.3at Draft 2.0 standard), with hardware “AT-Detect” output
Meets the IEC 61000-4-2/3/4/5/6 and IEC 60950 requirements for Surge, EMI and Isolation
Integrated surge protection for board level surge meets > 15kV Air Discharge (IEC61000-4-2), > 8kV Contact Discharge (IEC61000-4-2) and > 6kV Surge (IEC61000-4-5)
Integrated DC-DC converter with reduced EM emission for CISPR22/FCC part 15 Class B applications
Programmable DC current limit up to 800mA
Provides seamless support for local power down to 10V
Programmable frequency 100kHz to 500kHz
Low on resistance Hot Swap FET (0.8Ω typ)
Over temperature protection
About Akros Silicon
Headquartered in Folsom, California, Akros Silicon (Akros is a Greek word for “edge”) is a leading provider of highly differentiated system-level integrated circuits that provide advanced power management to the edge of the network. Akros Silicon’s disruptive silicon technology enables large scale deployment of network-attached appliances, such as VoIP phones, wireless LAN access points, RFID tag readers, point-of-sale terminals, networked cameras, remote access and home-networked systems—accelerating the convergence of data, audio, and video applications. For more information, visit http://www.AkrosSilicon.com.