I347-AT4 Datasheet, PDF (38/148 Pages) Intel Corporation – Intel® Ethernet Network Connection I347-AT4 Datasheet

I347-AT4—Device Functionality
3.6.3.4
Table 14.
Power State Upon Exiting Power Down
When the PHY exits power down (register 0_0.11 or 16_0.2) the active state depends
on whether the cable detect mode function is enabled (register 16_0.9:8 = 1x). If the
cable detect mode function is enabled, the PHY transitions to the cable detect mode
state first and wakes up only if there is a signal on the wire.
Power State after Exiting Power Down
3.6.4
3.6.5
Register 0_0.11
1b
x
1b to 0b
0b
1b to 0b
0b
Register 16_0.2
x
1b
0b
1b to 0b
0b
1b to 0b
Register 16_0.9:8
Behavior
xx
Power down.
xx
Power down.
00b
Transition to power up.
00b
Transition to power up.
1x
Transition to cable detect mode state.
1x
Transition to cable detect mode state.
Low Power Modes
Three low power modes are supported in the I347-AT4.
• IEEE 22.2.4.1.5 compliant power down
• Cable Detect Mode (Mode 1)
• Cable Detect Mode (Mode 2)
IEEE 22.2.4.1.5 power down compliance enables the PHY to be placed in a low-power
consumption state by register control.
Cable detect mode (Mode 1) enables the I347-AT4 to wake up when energy is detected
on the wire.
Cable detect mode (Mode 2) is identical to Mode 1 with the additional capability to
wake up a link partner. In Mode 2, the 10BASE-T link pulses are sent once every second
while listening for energy on the line.
Details of each mode follows.
Low Power Operating Modes
3.6.5.1
IEEE Power Down Mode
The standard IEEE power down mode is entered by setting register 0_0.11. In this
mode, the PHY does not respond to any SGMII signals except the MDC/MDIO. It also
does not respond to any activity on the copper media.
In this power down mode, the PHY cannot wake up on its own by detecting activity on
the media. It can only wake up by setting registers 0_0.11 and 16_0.2 = 0b.
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