# US 8,542,663 B2 · Standby mode for use in a device having a multiple channel physical layer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,542,663 B2 - Document ID: US8542663B2 - Status: Granted - Kind: B2 - Application number: 10/882,389 - Filed: 2004-07-02 - Published: 2005-02-10 - Granted: 2013-09-24 - Earliest claimed: 2003-07-03 - Assignees: Broadcom Corporation - Applicants: Kevin Brown; Richard G. Thousand; John Creigh - Inventors: Kevin Brown; Richard G. Thousand; John Creigh - Web page: https://patentgrep.com/patent/US8542663B2 ## Abstract The present invention provides a way of placing a physical layer device into a standby mode. After a link is established between multiple devices, a determination is made whether the device has data to transmit or whether a standby request was received from a link partner. If a standby request was received or the device has no data to transmit, standby mode is entered. In standby mode, unneeded circuitry is powered down. A transmitter in a channel and a receive path in a separate channel remain powered. While operating in standby mode, the PHY layer continuously transmits a standby code on the one or more channels that are not powered down. Standby mode is discontinued when a transceiver has data to transmit or when energy is detected on the powered down channels. Standby mode is also discontinued when no standby code is received, indicating a disconnect between devices. ## Claims ### Claim 1 A method for reducing power consumption in a first transceiver in communication with a remote transceiver and having a physical layer (PHY) with a multi-channel architecture, the method comprising: (a) initiating standby mode of operation when a period during which the first transceiver has no data to transmit exceeds a value of a wait timer; and (b) if it is determined in step (a) that standby mode should be initiated, (1) transmitting a standby code on a channel of the PHY to maintain a link between the first transceiver and the remote transceiver, and (2) powering down at least one circuit in the first transceiver. ### Claim 2 (depends on 1) The method of claim 1, further comprising: establishing a link between the first transceiver and the remote transceiver. ### Claim 3 (depends on 1) The method of claim 1, further comprising: (c) determining whether standby mode of operation should be discontinued; and (d) if it is determined in step (c) that standby mode should be discontinued, (1) ending transmission of the standby code, (2) transmitting an IDLE code, and (3) powering up at least one circuit that was powered down. ### Claim 4 (depends on 3) The method of claim 3, wherein step (c) comprises: (1) determining whether the first transceiver has data to transmit; (2) if it is determined in step (1) that the first transceiver has no data to transmit, determining whether an IDLE signal was received from the remote transceiver; (3) if it is determined in step (2) that an IDLE signal was received, discontinuing standby mode of operation; and (4) if it is determined in step (1) that the first transceiver has data to transmit, instructing the PHY to restore normal mode of operation. ### Claim 5 (depends on 4) The method of claim 4, further comprising: (5) if it is determined in step (2) that no IDLE signal was received, determining whether a standby signal is being received; (6) if it is determined that no standby signal is being received, re-establishing a link between the first transceiver and the remote transceiver. ### Claim 6 (depends on 4) The method of claim 4, wherein step (c)(2) comprises: powering down at least one unused transmitter; and powering down and declocking at least one unused receive path, wherein at least one transmitter in a first channel and at least one receive path in a second channel remain powered. ### Claim 7 (depends on 6) The method of claim 6, further comprising: locking relative phases of a plurality of channels to timing recovery of a single channel. ### Claim 8 (depends on 6) The method of claim 6, wherein step (d)(3) comprises: powering the at least one unused transmitter; and powering and clocking the at least one unused receive path. ### Claim 9 (depends on 7) The method of claim 7, wherein step (d)(3) comprises: unlocking the relative phases of the plurality of channels. ### Claim 10 (depends on 1) The method of claim 1, wherein the PHY is a 1000BASE-T PHY. ### Claim 11 (depends on 1) The method of claim 1, wherein the PHY is a S800BASE-T PHY. ### Claim 12 (depends on 1) The method of claim 1, wherein the standby code is transmitted using a three-level signal implementing unused codes in a specification of the PHY. ### Claim 13 (depends on 1) The method of claim 1, wherein the standby code is transmitted at a reduced peak-to-peak voltage amplitude. ### Claim 14 A method for reducing power consumption in a first transceiver in communication with a remote transceiver and having a 1000BASE-T physical layer (PHY) with a multi-channel architecture, the method comprising: (a) initiating standby mode of operation when a period during which the first transceiver has no data to transmit exceeds a value of a wait timer; (b) if it is determined in step (a) that standby mode should be initiated, (1) transmitting a standby code on a channel of the PHY to maintain a link between the first transceiver and the remote transceiver, and (2) powering down at least one circuit in the first transceiver; (c) determining whether standby mode of operation should be discontinued; and (d) if it is determined in step (c) that standby mode should be discontinued, (1) ending transmission of the standby code, (2) transmitting an IDLE code, and (3) powering up at least one circuit that was powered down. ### Claim 15 (depends on 14) The method of claim 14, further comprising: establishing a link between the first transceiver and the remote transceiver. ### Claim 16 A method for reducing power consumption in a first transceiver in communication with a remote transceiver and having a S800BASE-T physical layer (PHY) with a multi-channel architecture, the method comprising: (a) initiating standby mode of operation when a period during which the first transceiver has no data to transmit exceeds a value of a wait timer; (b) if it is determined in step (a) that standby mode should be initiated, (1) transmitting a standby code on a channel of the PHY to maintain a link between the first transceiver and the remote transceiver, and (2) powering down at least one circuit in the first transceiver; (c) determining whether standby mode of operation should be discontinued; and (d) if it is determined in step (c) that standby mode should be discontinued, (1) ending transmission of the standby code, (2) transmitting an IDLE code, and (3) powering up at least one circuit that was powered down. ### Claim 17 (depends on 16) The method of claim 16, further comprising: establishing a link between the first transceiver and the remote transceiver. ### Claim 18 A method for reducing power consumption in a first transceiver in communication with a remote transceiver and having an Ethernet physical layer (PHY), the method comprising: (a) initiating standby mode of operation when a period during which the first transceiver has no data to transmit exceeds a value of a wait timer; (b) if it is determined in step (a) that standby mode should be initiated, (1) transmitting a standby code on a channel of the PHY to maintain a link between the first transceiver and the remote transceiver, and (2) powering down at least one circuit in the first transceiver; (c) determining whether standby mode of operation should be discontinued; and (d) if it is determined in step (c) that standby mode should be discontinued, (1) ending transmission of the standby code, (2) transmitting an IDLE code, and (3) powering up at least one circuit that was powered down. ### Claim 19 A method for reducing power consumption in a first transceiver in communication with a remote transceiver and having a physical layer (PHY) with three or more channels, the method comprising: (a) initiating standby mode of operation when a period during which the first transceiver has no data to transmit exceeds a value of a wait timer; (b) if it is determined in step (a) that standby mode should be initiated, (1) transmitting a standby code on a channel of the PHY to maintain a link between the first transceiver and the remote transceiver, and (2) powering down at least one circuit in the first transceiver; (c) determining whether standby mode of operation should be discontinued; and (d) if it is determined in step (c) that standby mode should be discontinued, (1) ending transmission of the standby code, (2) transmitting an IDLE code, and (3) powering up at least one circuit that was powered down. ### Claim 20 A system for reducing power consumption in a first transceiver during data communication with a remote transceiver and having a physical layer (PHY) with a multi-channel architecture, the system comprising: means for initiating standby mode of operation when a period during which the first transceiver has no data to transmit exceeds a value of a wait timer; means for transmitting a standby code continuously on a channel of the PHY to maintain a logical link between the first transceiver and the remote transceiver, and means for powering down at least one circuit. ### Claim 21 (depends on 20) The system of claim 20, further comprising: means for determining whether standby mode of operation should be discontinued; and means for discontinuing standby mode of operation, including: means for ending transmission of the standby code, means for transmitting an IDLE code, and means for powering up at least one circuit that was powered down. ### Claim 22 (depends on 20) The system of claim 20, wherein the PHY is a 1000BASE-T PHY. ### Claim 23 (depends on 20) The system of claim 20, wherein the PHY is a S800BASE-T PHY. ### Claim 24 A first transceiver in communication with a remote transceiver for reducing power consumption during data communications, the first transceiver comprising: a physical layer (PHY), wherein the PHY includes: an auto-negotiation sublayer; a physical coding sublayer (PCS); a physical medium attachment (PMA) sublayer, wherein the PMA layer includes: a PHY control including a standby mode module, wherein the standby mode module is configured to: initiate standby mode of operation when a period during which the first transceiver has no data to transmit exceeds a value of a wait timer, control standby mode operation, and determine whether standby mode of operation should be discontinued. ### Claim 25 (depends on 24) The first transceiver of claim 24, wherein the PHY is a 1000BASE-T sublayer. ### Claim 26 (depends on 24) The first transceiver of claim 24, wherein the PHY is a S800BASE-T sublayer.