Agere Systems Inc.

Lsi Corporation

Lucent Technologies Inc.

Avago Technologies General IP (singapore) Pte. Ltd.

Nvidia Corporation

At+t Corp.

Agere Systems Guardian Corp.

Avago Technologies International Sales Pte. Limited

At&t Ipm Corp.

Mohammad Shafiul Mobin

Lane Allen Smith

Gregory W Sheets

Pervez Mirza Aziz

Vladimir Sindalovsky

Ye Liu

Paul H Tracy

David M Blaker

Amaresh Virupanagouda Malipatil

Gregory S Ellard

Kouros Azimi

Vishnu Balan

Kenneth Wade Paist

Haitao Xia

Himanshu Mahendra Thaker

Craig B Ziemer

Mark Trafford

Charles Albert Webb, Iii

Christopher John Abel

Xingdong Dai

Mark Ernest Thierbach

Rohit Rathi

Weiwei Mao

Matthew Tota

Marc Stephen Diamondstein

Dai Dai

Kalyan Mondal

Homayoon Sam

Gary Schiessler

Donald Raymond Laturell

Roger A Fratti

William Burdett Wilson

Adam Benjamin Healey

Ronald Lamar Freyman

Brett D Hardy

Raanan Ivry

Joseph Anidjar

Sivanand Simanapalli

Geoffrey Zhang

Dwight David Daugherty

Jeffrey H Saunders

Larry R Tate

Gregory Scott Winn

Yasser Ahmed

John Jansen

Lesley J Wu

Akkas T Sufi

Thomas F Gibbons, Jr

Akshay Shyam Pavagada Raghavendra

Vahid Marandi

Shaohua Yang

Sailesh Mansinh Merchant

Bruce Alexander Wilson

Cecil William Farrow

Freeman Yingquan Zhong

Michael Samuel Shaffer

Anup S Tirumala

Mehran Aliahmad

Max Jay Olsen

Lesley Jen-Yuan Wu

James D Chlipala

Eric Tyson

Sunil Srinivasa

Marta M Rambaud

Hitendra Dutt

Shiva Prasad Kotagiri

Chintan M Desai

Daniel J Udovic

Kaylan Mondal

Kai-Chuen Wong

Dil Afroz Mobin

Gregory A Kleese

Gregory Stephen Ellard

Rajesh Ramadoss

Ian Hughes

Dennis Farley

Robert Kapuschinsky

Gary E Schiessler

A receiver receives communications over a communication channel, which may distort an incoming communication signal. In order to counter this distortion, the frequency response of the receiver is manipulated by adjusting several parameters. Each parameter controls at least a portion of the frequency response of the receiver. The optimal values for the parameters are determined by modifying an initial set of values for the parameters through one or more stochastic hill climbing operations until a performance metric associated with the receiver reaches a local optimum. The modified values are displaced through one or more mutation operations. The stochastic hill climbing operations may subsequently be performed on the mutated values to generate the final values for the parameters.

Receiver and transmitter adaptation using stochastic gradient hill climbing with genetic mutation

An integrated circuit for a receiving link device includes a processing device to detect, using an equalizer of the receiving link device, that a receiver (RX) pre-cursor value is outside of a threshold value based on a target RX tap value. The processing device further generates, based on the detecting, a plurality of tap messages having a plurality of up or down commands to one of decrease or increase a corresponding transmitter (TX) pre-cursor value of a transmitting link device. The processing device further causes the plurality of tap messages to be provided to a local transmitter to be transmitted to the transmitting link device. The plurality of tap messages is to cause the transmitting link device to adjust the corresponding TX pre-cursor value.

Equalization adaptation schemes for high-speed links

A receiving link device includes a receiver (RX) to receive a data signal from a transmitting link device, the receiver including an equalizer to detect RX tap values and a processing device coupled to the receiver, the processing device to perform operations including: programming the receiver with information related to target RX tap values that are associated RX pre-cursors or RX post-cursors; detecting, using the equalizer, that an RX pre-cursor value is greater or less than a target RX tap value; generating, based on the detecting, a tap message including an up or a down command to decrease or increase a corresponding transmitter (TX) pre-cursor value of the transmitting link device; and causing the tap message to be provided to a local transmitter to be transmitted to a remote receiver of the transmitting link device, which causes the transmitting link device to adjust the corresponding TX pre-cursor value.

A receiver receives communications over a communication channel, which may distort an incoming communication signal. In order to counter this distortion, the frequency response of the receiver is manipulated by adjusting several frequency response parameters. Each frequency response parameter controls at least a portion of the frequency response of the receiver. The optimal values for the frequency response parameters are determined by modifying an initial set of values for the frequency response parameters through one or more of stochastic hill climbing operations until a performance metric associated with the receiver reaches a local maximum. The modified values are displaced through one or more mutation operations. The stochastic hill climbing operations may subsequently be performed on the mutated values to generate the final values for the frequency response parameters.

Receiver adaptation using stochastic gradient hill climbing with genetic mutation

In a computing system, various components/devices communicate with each other. For example, a microprocessor may communicate with memory or may communicate with another microprocessor over a link. Various factors such as the frequency and transmission speed of a signal can distort what is being communicated over a link. The problem becomes more pronounced as the transmission speed increases. To address this problem, devices on both ends of a link can cooperate to equalize the link. Equalization involves configuring the transmitting device to alter the signal being transmitted so that certain distortions introduced during transmission are negated by the time the signal arrives at the receiving device. Given that each link can have slightly different characteristics, appropriate equalization parameters need to be ascertained for each link. Introduced herein are improved techniques for performing equalization that are quick yet provide equalization parameters that are stable even in a noisy high-speed link.

Techniques for improving high-speed communications in a computing system

Embodiments are related to systems and methods for data transfer, and more particularly to systems and methods for providing non-standard bus information.

Systems and methods for channel information exchange in a PCIe environment

Embodiments are related to systems and methods for data transfer, and more particularly to systems and methods for providing transfer margin information.

Systems and methods for accurate transfer margin communication

An apparatus for processing data includes a decision feedback equalizer configured to sample an analog signal to yield digital data and a DC offset adaptation circuit. The decision feedback equalizer is configured to sample the equalized signal using at least one data latch at a first data latch threshold value and at a second data latch threshold value. The DC off set adaptation circuit is configured to calculate a DC off set in the analog signal based on the first data latch threshold value and on the second data latch threshold value.

DeSerializer DC offset adaptation based on decision feedback equalizer adaptation

An apparatus for processing data includes a linear equalizer, a load switchably connected to an output of the linear equalizer, a slicer configured to sample a signal derived from the output of the linear equalizer, and a detector circuit configured to detect an over-equalization condition in data to be sampled by the slicer and to connect the load to the output of the linear equalizer in the over-equalization condition.

Receiver bandwidth adaptation

Embodiments are related to systems and methods for data processing, and more particularly to systems and methods for enhancing margin in a serial data transfer.

Systems and methods for serial data transfer margin increase

Embodiments are related to systems and methods for data processing, and more particularly to systems and methods for clock recovery in a data receiver.

Systems and methods for SerDes physical layer qualification and mitigation

Methods and apparatus are provided for adapting transmitter equalization coefficients based on receiver gain adaptation. Equalization coefficients of a transmitter that communicates over a channel with a receiver are adapted by determining if a gain value for an amplifier in the receiver is within a limit of the amplifier; and preventing one or more adjustments to the transmitter equalization coefficients if the gain value does not satisfy the upper or lower limit of the amplifier. The gain adjustments comprise, for example, up and down requests for the transmitter equalization coefficients. One or more enable flags can optionally be set based on whether the gain value is within the limit of the amplifier.

Methods and apparatus for adapting transmitter equalization coefficients based on receiver gain adaptation

Described embodiments provide for, in a SerDes device, an adaptation process that adjusts data path gain through programmable-bias based on process, voltage, temperature (PVT) and data rate changes. Such adaptation process extends bias current dynamic range, and low frequency gain can be programmed to a desired target range of values for a given variable gain amplifier (VGA) setting at any PVT and data rate corner. A receive (RX) data path structure auto-adapts data path gain through programmable bias based on sensed PVT and data rate changes. The low frequency attenuation/gain range is extended, and can be programmed to a desirable targeted range by a SerDes device RX adaptive process for a given VGA and linear equalizer (LEQ) setting at any given PVT and data rate condition.

Data rate and PVT adaptation with programmable bias control in a SerDes receiver

In described embodiments, process, voltage, temperature (PVT) compensation in a serializer/deserializer (SerDes) device employs a closed loop adaptation compensation that is incorporated into the SerDes receiver adaptation process. A detection method, where the adapted decision feedback equalizer (DFE) target level (e.g., tap H) is monitored, employs this DFE target level when implementing a closed loop variable gain amplifier adaptation. The DFE target level in conjunction with the VGA level is used to control the PVT setting to maintain target SerDes data path gain by detecting aPVT corner condition. The detected PVT corner condition is employed to generate a control signal to further adjust the LEQ and DFE data path differential pair gain as required by the PVT condition.

SerDes PVT detection and closed loop adaptation

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Whitehall, PA, United States of America

Mohammad Shafiul Mobin