Power dissipation management for wired transceivers
A system, method and apparatus for reducing a power consumed by a physical layer device (PHY). A length of a cable connecting the PHY to a link partner is determined. Based on the length, power provided to one or more components of the PHY, or any portion thereof, is reduced. The power provided is reduced while maintaining a level of reliability specified by a protocol governing operation of the PHY. The length can be determined using time-domain reflectometry (TDR) techniques. Any portion of an echo cancellation filter, a crosstalk filter, an equalizer, a precoder, an analog-to-digital converter (ADC), a digital-to-analog converter (DAC), a forward error correction (FEC) decoder and/or an FEC coder can be powered-down or power-optimized to reduce the overall power consumed by the PHY. The protocol governing operation of the PHY can be IEEE 802.3.
1. An apparatus comprising:
a physical layer device (PHY), configured to:
determine a length of a cable communicatively coupling the PHY to a link partner; and
switch one or more components of the PHY to a power saving mode based on the length of the cable by modifying a parameter of at least one of the one or more components, thereby reducing an amount of power consumed by the PHY.
2. The apparatus of claim 1 , wherein the PHY is further configured to determine the length of the cable using time-domain reflectometry (TDR) techniques.
3. The apparatus of claim 1 , wherein the one or more components include at least one of:
an echo cancellation filter;
a crosstalk filter;
an equalizer;
a precoder;
a forward error correction (FEC) decoder; and
a FEC coder.
4. The apparatus of claim 1 , wherein the PHY is further configured to implement at least one protocol governed by IEEE 802.3.
5. The apparatus of claim 1 , wherein the PHY is further configured to switch the one or more components to the power saving mode when the length of the cable is less than a threshold length.
6. The apparatus of claim 5 , wherein the threshold length is a predetermined fixed distance.
7. The apparatus of claim 1 , wherein the PHY is further configured to turn off the one or more components based on the length of the cable.
8. The apparatus of claim 1 , wherein the one or more components comprises an echo cancellation filter, and wherein the PHY is further configured to turn off one or more taps of the echo cancellation filter based on the length of the cable.
9. The apparatus of claim 1 , wherein the one or more components comprises a crosstalk filter, and wherein the PHY is further configured to turn off one or more taps of the crosstalk filter based on the length of the cable.
10. The apparatus of claim 1 , wherein the one or more components comprises an equalizer, and wherein the PHY is further configured to turn off one or more taps of the equalizer based on the length of the cable.
11. The apparatus of claim 1 , wherein the one or more components comprises at least one of an analog-to-digital converter (ADC) and a digital-to-analog converter (DAC), and wherein the PHY is further configured to reduce at least one of a resolution and linearity requirement of at least one of the ADC and the DAC based on the length of the cable.
12. The apparatus of claim 1 , wherein the one or more components comprises a FEC coder, and wherein the PHY is further configured to reduce a coding length of the FEC coder based on the length of the cable.
13. The apparatus of claim 1 , wherein the one or more components comprises an iterative FEC decoder, and wherein the PHY is further configured to reduce a number of iterations in the iterative FEC decoder based on the length of the cable.
14. The apparatus of claim 1 , wherein the one or more components comprises a FEC decoder, and wherein the PHY is further configured to reconfigure the FEC decoder from a soft decision FEC decoder to a hard decision FEC decoder based on the length of the cable.
15. An apparatus comprising:
a transceiver, comprising a plurality of physical layer devices (PHYs), comprising one or more components,
wherein at least one of the plurality of PHYs is configured to determine a length of a cable communicatively coupling the at least one of the plurality of PHYs to at least one link partner,
wherein the transceiver is configured to determine a first cumulative cable length for a first set of the plurality of PHYs,
wherein the transceiver is configured to determine a second cumulative cable length for a second set of the plurality of PHYs,
wherein the transceiver is configured to allocate a first quantity of power to the first set of the plurality of PHYs when the first cumulative cable length is above a threshold length, and
wherein the transceiver is configured to allocate a second quantity of power to the second set of the plurality of PHYs when the second cumulative cable length is below the threshold length.
16. The apparatus of claim 15 , wherein the first quantity of power is greater than the second quantity of power.
17. The apparatus of claim 16 , wherein at least one of the first set and second set is configured to switch the one or components to a power saving mode based on at least one of the first quantity, the second quantity, and the length of the cable.
18. The apparatus of claim 15 , wherein the one or more components comprise at least one of:
an echo cancellation filter;
a crosstalk filter;
an equalizer;
a precoder;
an analog-to-digital converter (ADC); and
a digital-to-analog converter (DAC).
19. The apparatus of claim 15 , wherein the threshold length is a predetermined fixed distance.
20. The apparatus of claim 15 , wherein the first set of PHYs and second set of PHYs operate independently from one another.