Rambus Inc.

Intel Corporation

Altera Corporation

Lattice Semiconductor Corporation

Jihong Ren

Brian S Leibowitz

Jared L Zerbe

Hae-Chang Lee

Qi Lin

Fariborz Assaderaghi

Teva J Stone

Ruwan Ratnayake

Kyung Suk Oh

John M Wilson

Lei Luo

Barry William Daly

John Cronan Eble, Iii

Wayne D Dettloff

Hsuan-Jung Su

Masum Hossain

Jaeha Kim

Wenyi Jin

Farshid Aryanfar

Yu Liao

Dinesh D Patil

Reza Navid

Joong-Ho Kim

John Wilson

An integrated circuit (IC) chip includes transfer circuitry to transfer signals between the IC chip and a second IC chip. The transfer circuitry includes equalization circuitry having at least one tap to equalize the signals. The equalization circuitry includes a tap weight adapter circuit to generate a respective tap weight for each of the at least one tap based on edge information of previously transferred signals.

Edge based partial response equalization

A transceiver architecture supports high-speed communication over a signal lane that extends between a high-performance integrated circuit (IC) and one or more relatively low-performance ICs employing less sophisticated transmitters and receivers. The architecture compensates for performance asymmetry between ICs communicating over a bidirectional lane by instantiating relatively complex transmit and receive equalization circuitry on the higher-performance side of the lane. Both the transmit and receive equalization filter coefficients in the higher-performance IC may be adaptively updated based upon the signal response at the receiver of the higher-performance IC.

Methods and circuits for asymmetric distribution of channel equalization between devices

An intergrated circuit (IC) chip includes receiver circuitry to receive signals from a second IC chip. The receiver circuitry includes equalization circuitry having at least one tap to equalize the signals. The equalization circuitry includes a tap weight adapter circuit to generate at least one tap weight corresponding to the at least one tap based on edge information of previously received signals.

Receiver circuitries having multiple branches, such as unrolled feedback equalizers and fractional-rate receivers, may present differences between filtering elements of different branches with common filter inputs. Embodiments include devices capable of calibration that compensates such differences. The devices may be capable of introducing front-end offsets to emphasize the mismatches, and sweep filter input values to calculate the mismatches, and introducing offsets in the branches to compensate for the mismatches. Methods for use of the calibration devices are also described.

Calibration for mismatch in receiver circuitry with multiple samplers

A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.

Receiver with clock recovery circuit and adaptive sample and equalizer timing

An integrated circuit (IC) memory device includes receiver circuitry to receive write data from a memory controller. The receiver circuitry includes equalization circuitry having at least one tap to equalize the write data. The equalization circuitry includes a tap weight adapter circuit to adaptively generate a tap weight for the tap from an edge analysis of previously received write data.

A low-power, high-performance source-synchronous chip interface which provides rapid turn-on and facilitates high signaling rates between a transmitter and a receiver located on different chips is described in various embodiments. Some embodiments of the chip interface include, among others: a segmented 'fast turn-on' bias circuit to reduce power supply ringing during the rapid power-on process; current mode logic clock buffers in a clock path of the chip interface to further reduce the effect of power supply ringing; a multiplying injection-locked oscillator (MILO) clock generator to generate higher frequency clock signals from a reference clock; a digitally controlled delay line which can be inserted in the clock path to mitigate deterministic jitter caused by the MILO clock generator; and circuits for periodically re-evaluating whether it is safe to retime transmit data signals in the reference clock domain directly with the faster clock signals.

Method and apparatus for source-synchronous signaling

This disclosure provides a clock recovery circuit for a multi-lane communication system. Local clocks are recovered from the input signals using respective local CDR circuits, and associated CDR error signals are aggregated or otherwise combined. A global recovered clock for shared use by the local CDR circuits is generated at a controllable oscillation frequency as a function of a combination of the error signals from the plurality of receivers. A voltage- or current-controlled delay line can also be used to phase adjust the global recovered clock to mitigate band-limited, lane-correlated, high frequency jitter.

Clock and data recovery having shared clock generator

Devices and methods for adjusting operation of a receiver that includes a continuous time linear equalizer, a decision feedback equalizer, and a feed forward equalizer. Operation of the receiver may be controlled by determining whether the receiver is operating in operation region using frequency responses of the feed forward equalizer at a first frequency and a second frequency and using the frequency responses of the decision feedback equalizer at the first frequency and the second frequency. If the operation is outside the frequency, a parameter of the continuous time linear equalizer is adjusted based on the frequency responses of the feed forward equalizer and the decision feedback equalizer.

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Sunnyvale, CA, United States of America

Jihong Ren