# US 2008/0304559 A1 · System for automatic bandwidth control of equalizer adaptation loops > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2008/0304559 A1 - Document ID: US20080304559A1 - Status: Published application - Kind: A1 - Application number: 11/760,844 - Filed: 2007-06-11 - Published: 2008-12-11 - Earliest claimed: 2007-06-11 - Assignees: LSI Corporation - Inventors: Ephrem C. Wu; Ye Liu; Freeman V. Zhong - Web page: https://patentgrep.com/patent/US20080304559A1 ## CPC - H04L 25/03057: {with a recursive structure (H04L25/03031 takes precedence)} - H04L 2025/03681: {Control of adaptation} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A method to reduce peak power consumption during adaptation for an IC with multiple serial link transceivers including the steps of (A) inactivating equalizer adaptation loops until a triggering event occurs, (B) when the triggering event occurs, determining whether the triggering event is a minor change or a major change, (C) when the triggering event is a minor change, spreading out activation of adaptation loops in time, and (D) when the triggering event is a major change, simultaneously activating all adaptation loops. ## Claims ### Claim 1 A method to reduce power consumption in serial transceivers comprising the steps of: (A) inactivating equalizer adaptation loops until a triggering event occurs; (B) when the triggering event occurs, determining whether the triggering event comprises a minor change or a major change; (C) when the triggering event comprises a minor change, spreading out activation of the equalizer adaptation loops in time; and (D) when the triggering event comprises a major change, simultaneously activating all of the equalizer adaptation loops. ### Claim 2 (depends on 1) The method according to claim 1, further comprising simultaneously activating all of the equalizer adaptation loops to reach a steady state condition prior to inactivating the equalizer adaptation loops. ### Claim 3 (depends on 2) The method according to claim 2, wherein all of the equalizer adaptation loops are simultaneously activated in response to a reset. ### Claim 4 (depends on 1) The method according to claim 1, further comprising simultaneously activating all equalizer adaptation loops of a subset of serial transceivers in a switch card associated with a line card to reach a steady state condition prior to inactivating the equalizer adaptation loops of the subset of serial transceivers associated with the line card. ### Claim 5 (depends on 4) The method according to claim 4, wherein the equalizer adaptation loops of the subset of serial transceivers are activated in response the line card being coupled to the switch. ### Claim 6 (depends on 1) The method according to claim 1, wherein the triggering event comprises a change in a factor selected from the group consisting of channel characteristics and operating environment. ### Claim 7 (depends on 1) The method according to claim 1, wherein the triggering event comprises a change in a parameter selected from the group consisting of temperature, humidity and supply voltage and one or more master coefficients. ### Claim 8 (depends on 1) The method according to claim 1, wherein the triggering event comprises a change in a parameter selected from the group consisting of skin loss, dielectric loss, return loss and one or more master coefficients. ### Claim 9 (depends on 1) The method according to claim 1, wherein the triggering event comprises a periodic wake-up. ### Claim 10 (depends on 1) The method according to claim 1, wherein a magnitude of the change is determined based on a first threshold and a second threshold. ### Claim 11 (depends on 10) The method according to claim 10, wherein the change is minor when said magnitude is greater than or equal to said first threshold and less than said second threshold. ### Claim 12 (depends on 10) The method according to claim 10, wherein the change is major when said magnitude is greater than or equal to said second threshold. ### Claim 13 (depends on 1) The method according to claim 1, wherein the equalizer adaptation loops are selected from the group consisting of decision feedback equalization (DFE), linear equalization (LE) and gain adaptation. ### Claim 14 A method for automatic adaptation bandwidth control in an IC with multiple serial link transceivers comprising: a training phase configured to simultaneously set all adaptation parameters of said serial link transceivers; and an operating phase configured to activate one or more adaptation loops of said serial link transceivers in response to an environmental change. ### Claim 15 (depends on 14) The method according to claim 14, wherein the training phase comprises the steps of: activating adaptation for all taps and all channels of said multiple serial link transceivers; determining when all of said taps and channels are in a steady state condition; determining mean values for coefficients of said taps and channels; and freezing all of said taps and channels with said mean values and deactivating adaptation. ### Claim 16 (depends on 14) The method according to claim 14, wherein the operating phase comprises the steps of: inactivating equalizer adaptation loops until a triggering event occurs; when the triggering event occurs, determining whether the triggering event is a minor change or a major change; when the triggering event is a minor change, spreading out activation of the equalizer adaptation loops in time; and when the triggering event is a major change, simultaneously activating all of the equalizer adaptation loops. ### Claim 17 (depends on 16) The method according to claim 16, wherein the triggering event comprises a change in a parameter selected from the group consisting of channel characteristics, operating environment, temperature, humidity, supply voltage, skin loss, dielectric loss, return loss and one or more master coefficients. ### Claim 18 (depends on 16) The method according to claim 16, wherein the triggering event comprises a periodic wake-up. ### Claim 19 (depends on 17) The method according to claim 17, wherein (i) the change is minor when a magnitude of the change is greater than or equal to a first threshold and less than a second threshold and (ii) the change is major when said magnitude is greater than or equal to said second threshold. ### Claim 20 An apparatus comprising: a plurality of serial link transceivers; and an automatic adaptation bandwidth control circuit configured to (A) inactivate equalizer adaptation loops of said plurality of serial link transceivers until a triggering event occurs, (B) determine whether the triggering event is a minor change or a major change in response to an occurrence of the triggering event, (C) spread out activation of the equalizer adaptation loops in time in response to a minor change, and (D) simultaneously activate all of the equalizer adaptation loops in response to a major change.