Qualcomm® ETHOS®-Designed Green Ethernet
In every market that Qualcomm Atheros’ ETHOS solutions serve, low-power is critical to performance. Qualcomm Atheros Ethernet engineering team is committed to delivering industry-leading low power to extend battery charges of computing products, reduce the carbon footprint of home routers, gateways, consumer electronics, and enterprise access points, and enable product compliance with regulations such as the new 802.3az for Energy Efficient Ethernet, Energy Star, and the European Code of Conduct on Energy Efficiency. This commitment has resulted in the industry-leading low power solutions, which gives our customers’ products a competitive, low-power advantage.
IEEE 802.3az Compliance
All Qualcomm Atheros new-generation Ethernet solutions support the IEEE 802.3az Energy-Efficient Ethernet standard, which features enhancements to significantly lower power consumption when networks are idle. It’s estimated by the ITU World Summit on Information Society that 5 to 10 percent of the world’s electrical demand is generated by the information and communications technology (ICT) sector. Approximately 50 percent of this demand is wasted by equipment that is powered on but idle. The 802.3az offers mechanisms and protocols that transition interfaces into low-power state during periods of low utilization and allow communication of energy-saving information between link partners without interrupting the network link or performance.

Figure 1: Power savings
Qualcomm Atheros Proprietary Low-Power Technologies
Qualcomm Atheros offers Dynamic Power Management features throughout its Ethernet portfolio to reduce chip- and system-level power. These market-proven ETHOS mechanisms are dedicated to increasing standby or sleep mode of the chip or system, and providing incremental power savings over those achieved by the IEEE 802.3az.
Chip and System-Level Power Savings
- Wake-on-LAN (WoL): When the Wake-on-LAN feature detects no active Ethernet frames on the network, it notifies the power control unit (PCU) to turn off the main system functions and enter into sleep state. Qualcomm Atheros’ PHY or switch then operates in WoL mode, with a monitor assessing packet traffic on both the LAN and WAN sides. When the monitor detects a packet on the network, it interrupts the system’s sleep and prompts it into active mode. WoL can result in total system power savings of more than 50%.
Chip-Level Power Savings
- Analog Front End: The AFE eliminates the need for an extra power supply rail, eliminating up to 300 mW per Gigabit Ethernet port and achieving normalized maximum power per port.
- Automatic Power Savings @ Media Disconnect: Designed to reduce power in computing systems, APS supports automatic and active-state power management, detecting link-down and no-activity states to allow the system to shift into sleep mode. It offers additional power savings by selecting the lowest link speed necessary for transmissions.
- Cable Length Detection: This intelligence detects cable length at link-up, classifies it into three distinct length categories and automatically adjusts the power utilization based on cable length, resulting in chip power reduction up to 20%.
- Access Control Lists: ACL brings a new level of Ethernet intelligence to the home in Qualcomm Atheros’ 5-port and 7-port switches. An advanced function typically reserved for enterprise switching solutions, Access Control Lists enables quicker switching functions to reduce chip power.











