Intel Corporation

Shenggao Li

Fulvio Spagna

Sujatha Gowder

Ji Chen

Wenyan Vivian Jia

Stefan Rusu

Yikui Jen Dong

Guluke Tong

Xiaoqing Wang

Roan M Nicholson

Michael V De Vita

Issy Kipnis

Kenneth R Smits

Edward E Helder

Brandon M Walters

Mahesh M Chheda

Michael De Vita

Some embodiments include apparatus having multiple samplers in a decision feedback equalizer (DFE). The multiple samplers include at least two samplers and are configured to be activated in a first mode of the DFE to receive first input information from a summing circuit. At least one of the samplers is configured to be deactivated in a second mode of the DFE. At least one of the samplers is configured to be activated in the second mode of the DFE to receive second input information from the summing circuit.

Multi pulse amplitude modulation signaling decision feedback equalizer having power differentiating modes and tap-weight re-configuration

Embodiments include apparatuses, methods, and systems including a decision feedback equalizer (DFE). The DFE includes a first summer circuit, a second summer circuit, a decision circuit, and a tap-delay line including a number of delay elements. The first summer circuit is to add together an analog signal and a first set of weighted feedback taps {h(j+1), . . . h(m)} of time delayed signals of a detected symbol to generate a first summand. The second summer circuit is to add together a second set of weighted feedback taps {h(k+1), h(n)} of time delayed signals of the detected symbol to generate a second summand. The decision circuit is to receive at least the first summand and the second summand, to generate the detected symbol based on a sum including the first summand and the second summand. Other embodiments may also be described and claimed.

Multi-tap decision feedback equalizer (DFE) architecture with split-path summer circuits

A circuit may comprise a first node, a ring oscillator, a regulator, and a Kvcc compensation circuit. The first node may be a supply node to provide a supply voltage for the circuit. The ring oscillator may be formed from inverters. The regulator may use a single transistor between the first node and a second node for powering the oscillator. The K compensation circuit may be used to provide to the oscillator a variable capacitive load that is dependent on the supply at the first supply node, and it may drag oscillator frequency down when the first node supply goes up.

Circuits for digital and analog controlled oscillators

Some embodiments include apparatus and methods using a first latch in a decision feedback equalizer (DFE), a second latch in the DFE, and circuitry coupled to the first and second latches. The second latch includes a first input node coupled to an output node of the first latch. The circuitry includes a first input node coupled to the first output node, a second input node coupled to a second output node of the second latch, and an output node to provide information having a first output value based on first values of information at the first and second output nodes and a second output value based on second values of information at the first and second output nodes.

Supply voltage adaptation via decision feedback equalizer

Automatic digital sensing and compensation of frequency drift caused by temperature, aging, and/or other effects may be provided by including a compensation capacitor array and a sensing logic. The sensing logic may be configured to detect a drift in a first control signal and to provide the compensation capacitor array with a second control signal. The second control signal is configured to cause an adjustment of capacitance in the compensation capacitor array based on the detected drift in the first control signal.

Compensation for digitally controlled oscillator apparatus and method

Described is an apparatus for clock synchronization. The apparatus comprises a pair of interconnects; a first die including a first phase interpolator having an output coupled to one of the interconnects; and a second die, wherein the pair of interconnects is to couple the first die to the second die.

Clock synchronization apparatus and method

Some embodiments include apparatus having sampling circuitry, a first circuit path, a second circuit path, and a digitally controlled oscillator (DCO). The sampling circuit samples an input signal and provide data information and phase error information based on the input signal. A first circuit path provides proportional control information based on the data information and phase error information. A second circuit path provides integral control information based on the data information and phase error information. The first circuit path operates at a frequency higher than the second circuit path. The DCO generates a clock signal and controls the timing of the clock signal based on the integral control information and the proportional control information.

Programmable clock data recovery (CDR) system including multiple phase error control paths

Described is an apparatus comprising: a first phase frequency detector (PFD) to determine a coarse phase difference between a first clock signal and a second clock signal, the first PFD to generate a first output indicating the coarse phase difference; and a second PFD, coupled to the first PFD, to determine a fine phase difference between the first clock signal and the second clock signal, the second PFD to generate a second output indicating the fine phase difference.

Phase frequency detector

Embodiments include apparatuses, methods, and systems for open-loop voltage regulation and drift compensation for a digitally controlled oscillator (DCO). In embodiments, a communication circuit may include a DCO, an open-loop voltage regulator, and a calibration circuit. The open-loop voltage regulator may receive a calibration voltage and may generate a regulated voltage. The regulated voltage may be passed to the DCO. During a calibration mode, the calibration circuit may compare the regulated voltage to a reference voltage and adjust the calibration voltage based on the comparison to provide the regulated voltage with a target value. During a monitoring mode, the calibration circuit may receive a tuning code that is used to tune the DCO and further adjust the calibration voltage based on a value of the tuning code.

Open-loop voltage regulation and drift compensation for digitally controlled oscillator (DCO)

An apparatus is described that includes a receiver. The receive includes a data sampler, a positive error sampler and a negative error sampler each having respective inputs coupled to a same differential channel. The receiver also includes circuitry to drive the respective inputs, the circuitry to place a same calibration voltage on the differential channel to calibrate each of the data sampler, positive error sampler and negative error sampler with the same calibration voltage.

High performance receiver with single calibration voltage

Apparatus and method for clock synchronization for inter-die synchronized data transfer

Some embodiments include apparatus and methods using a first latch in a decision feedback equalizer (DFE), a second latch in the DFE, and circuity coupled to the first and second latches. The second latch includes a first input node coupled to an output node of the first latch. The circuitry includes a first input node coupled to the first output node, a second input node coupled to a second output node of the second latch, and an output node to provide information having a first output value based on first values of information at the first and second output nodes and a second output value based on second values of information at the first and second output nodes.

Some embodiments include apparatuses having a first circuit portion, a second circuit portion, and a third circuit portion. The first circuit portion includes a first transistor to receive a first signal of a differential signal pair and a second transistor to receive a second signal of the differential signal pair. The second circuit portion is coupled to the first and second transistors and a first supply node, the second circuit portion including a first output node and a second output node to provide an output signal pair based on the differential signal pair. The third circuit portion includes a first diode-connected transistor coupled between the first output node and a second supply node and a second diode-connected transistor coupled between the second output node and the second supply node.

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Pleasanton, CA, United States of America

Shenggao Li