82567—Datasheet
3.2
Power Saving Features
This section provides information about the low power configurations for the 82567.
3.2.1
Intel® Auto Connect Battery Saver (ACBS)
Intel Auto Connect Battery Saver for the 82567 is a hardware-only feature that
automatically reduces the PHY to a lower power state when the power cable is
disconnected. When the power cable is reconnected, it will renegotiate the line speed
following IEEE specs for autonegotiation. By default, autonegotiation starts at 1GHz,
then 100 Mb full duplex/half duplex, then 10 Mb full duplex/half duplex.
Note:
Intel Auto Connect Battery Saver for the 82567 is only supported if autonegotiation is
enabled. If link speed is forced and the network cable is disconnected, the 82567 will
not enter ACBS, resulting in higher power consumption than specified in section 4.6.
82567 ACBS works in both S0 and Sx states. Unlike the 82566 External ACBS
implementation, 82567 ACBS requires no BIOS, software, or external on-board
hardware, limiting BOM cost and making implementation easier. When the 82567 PHY
is in ACBS mode, the LAN drivers stay loaded and the PHY consumes 37 mW (Solution
power is 63 mW). The crystal and LCI/GLCI interface clock still run, but all unneeded
internal clocks are gated. Since 82567 ACBS has no driver control, the feature is always
enabled, allowing power savings by default. The table below compares 82566 External
ACBS implementation and 82567 ACBS implementation:
82566 ACBS
82567 ACBS
Needs on board hardware
(energy detect circuit, power
FET Switch) (BOM Cost
~$0.2)
HW
No external BOM ($0)
No Driver control. Feature
always enabled. Enabling/
Disabling ACBS is not possible
from the driver.
Driver controls entry into
ACBS. Enabling/Disabling
ACBS possible from driver.
Driver
Implementation
(HW/SW/FW)
Minor changes needed for
LAN_PHY_PWR_CTRL (ICH
output) configuration.
BIOS
FW
No BIOS changes needed
NVM Soft Straps and GbE
NVM needs to be set up.
NVM does not need to be set
up.
Supported in both AC and DC
modes.
AC/DC modes
Sx support
Supported only in DC mode
Cannot enter ACBS mode in
Sx states.
Can enter ACBS mode in both
S0 and Sx states
3.3/1.8/1.05 V are all turned
off in IVRd/IVRi
3.3/1.8-1.9/1.05 V rails are all
left on
LAN Power Rails
configurations
PHY Power
Consumption
37 mW PHY power (63 mW
solution power)
~7mW
3.2.2
Link Speed Battery Saver
Link Speed Battery Saver is a power saving feature that negotiates to the lowest speed
possible when a Mobile system operates in DC mode to save power. When in AC mode,
where performance is more important than power, it negotiates to the highest speed
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INTEL [ INTEL ]
