Abstract: Methods and systems are described for receiving a reference clock signal and a phase of a local oscillator signal at a dynamically-weighted XOR gate comprising a plurality of logic branches, generating a plurality of weighted segments of a phase-error signal, the plurality of weighted segments including positive weighted segments and negative weighted segments, each weighted segment of the phase-error signal having a respective weight applied by a corresponding logic branch of the plurality of logic branches, generating an aggregate control signal based on an aggregation of the weighted segments of the phase-error signal, and outputting the aggregate control signal as a current-mode output for controlling a local oscillator generating the phase of the local oscillator signal, the local oscillator configured to induce a phase offset into the local oscillator signal in response to the aggregate control signal.

Abstract: Methods and systems are described for receiving, at a data-driven phase comparator circuit, a plurality of data signals in parallel and one or more phases of a local oscillator signal, the data-driven phase comparator circuit comprising a plurality of partial phase comparators, generating a plurality of partial phase-error signals using the partial phase comparators, each partial phase-error signal generated by receiving (i) a corresponding phase of the local oscillator signal and (ii) a corresponding data signal of the plurality of data signals and responsive to a determination that a transition occurred in the corresponding data signal, generating the partial phase-error signal based on a comparison of the corresponding phase of the local oscillator signal and the corresponding data signal, and generating a composite phase-error signal by summing the plurality of partial phase error signals for setting a local oscillator in a lock condition.

Abstract: Methods and systems are described for receiving a plurality of signals via a plurality of wires of a multi-wire bus, the plurality of signals corresponding to symbols of a codeword of a vector signaling code, generating, using an interconnected resistor network connected to the plurality of wires of the multi-wire bus, a plurality of combinations of the symbols of the codeword of the vector signaling code on a plurality of output nodes, the plurality of output nodes including a plurality of pairs of sub-channel output nodes associated with respective sub-channels of a plurality of sub-channels, and generating a plurality of sub-channel outputs using a plurality of differential transistor pairs, each differential transistor pair of the plurality of differential transistor pairs connected to a respective pair of sub-channel output nodes of the plurality of pairs of sub-channel output nodes.

Abstract: Methods and systems are described for receiving a set of input bits at a plurality of drivers and responsively generating an ensemble of signals, each respective signal of the ensemble of signals generated by receiving a subset of input bits at a respective driver connected to a respective wire of a multi-wire bus, the received subset of bits corresponding to sub-channels associated with the respective wire, generating a plurality of weighted analog signal components, each weighted analog signal component (i) having a corresponding weight and sign selected from a set of wire-specific sub-channel weights associated with the respective wire and (ii) modulated by a corresponding bit of the received subset of bits, and generating the respective signal by forming a summation of the plurality of weighted analog signal components at a common node connected to the respective wire for transmission over the respective wire of the multi-wire bus.

Abstract: Methods and systems are described for receiving, at an input differential branch pair, a set of input signals, and responsively generating a first differential current, receiving, at an input of an offset voltage branch pair, an offset voltage control signal, and responsively generating a second differential current, supplementing a high-frequency component of the second differential current by injecting a high-pass filtered version of the set of input signals into the input of the offset voltage branch pair using a high-pass filter, and generating an output differential current based on the first and second differential currents using an amplifier stage connected to the input differential branch pair and the offset voltage branch pair.

Abstract: Transmission of baseband and carrier-modulated vector codewords, using a plurality of encoders, each encoder configured to receive information bits and to generate a set of baseband-encoded symbols representing a vector codeword; one or more modulation circuits, each modulation circuit configured to operate on a corresponding set of baseband-encoded symbols, and using a respective unique carrier frequency, to generate a set of carrier-modulated encoded symbols; and, a summation circuit configured to generate a set of wire-specific outputs, each wire-specific output representing a sum of respective symbols of the carrier-modulated encoded symbols and at least one set of baseband-encoded symbols.

Abstract: Methods and systems are described for receiving an input data voltage signal at a first data decision circuit of set of pipelined data decision circuits, receiving an aggregate decision feedback equalization (DFE) correction current signal from a first analog current summation bus, the aggregate DFE correction current signal comprising a plurality of DFE tap-weighted currents from respective other data decision circuits of the set of pipelined data decision circuits, determining a data output decision value based on the received input data voltage signal and the received aggregate DFE correction current signal, and generating at least one outbound DFE tap-weighted current on at least one other analog current summation bus connected to at least one other data decision circuit of the set of pipelined data decision circuits.

Abstract: Methods and systems are described for receiving N phases of a local clock signal and M phases of a reference signal, wherein M is an integer greater than or equal to 1 and N is an integer greater than or equal to 2, generating a plurality of partial phase error signals, each partial phase error signal formed at least in part by comparing (i) a respective phase of the M phases of the reference signal to (ii) a respective phase of the N phases of the local clock signal, and generating a composite phase error signal by summing the plurality of partial phase error signals, and responsively adjusting a fixed phase of a local oscillator using the composite phase error signal.

Abstract: Methods and systems are described for receiving a control step input at a binary-to-thermometer decoder and responsively generating bits of a thermometer codeword representative of the control step input, providing the bits of the thermometer codeword to a plurality of differential pairs comprising a first transistor and a second transistor, each differential pair configurable for one of directing current to an in-phase (I) common node or directing current to a quadrature phase (Q) common node and switching between directing current to the I common node and the Q common node, and forming an output signal based on current drawn through the I and Q common nodes, the output signal having an intermediate phase with respect to a first and a second reference signal.

Abstract: Pre-charging two or more sets of nodes to set a differential output of a multi-input summation latch connected to the two or more sets of nodes in a pre-charged state, the two or more sets of nodes comprising a set of data signal nodes and a set of DFE correction nodes, in response to a sampling clock, generating a differential data voltage and an aggregate differential DFE correction signal, and generating a data decision by driving the differential output of the multi-input summation latch into one of two possible output states according to a summation of the differential data voltage signal and the aggregate differential DFE correction signal and subsequently holding the data decision by holding the differential output of the multi-input summation latch in a latched state for a duration determined by the sampling clock.

Abstract: Methods and systems are described for receiving, at a data-driven phase comparator circuit, a plurality of data signals in parallel and one or more phases of a local oscillator signal, the data-driven phase comparator circuit comprising a plurality of partial phase comparators, generating a plurality of partial phase-error signals using the partial phase comparators, each partial phase-error signal generated by receiving (i) a corresponding phase of the local oscillator signal and (ii) a corresponding data signal of the plurality of data signals and responsive to a determination that a transition occurred in the corresponding data signal, generating the partial phase-error signal based on a comparison of the corresponding phase of the local oscillator signal and the corresponding data signal, and generating a composite phase-error signal by summing the plurality of partial phase error signals for setting a local oscillator in a lock condition.

Abstract: Methods and systems are described for receiving a signal to be sampled and responsively generating, at a pair of common nodes, a differential current representative of the received signal, receiving a plurality of sampling interval signals, each sampling interval signal received at a corresponding sampling phase of a plurality of sampling phases, for each sampling phase, pre-charging a corresponding pair of output nodes using a pre-charging FET pair receiving the sampling interval signal, forming a differential output voltage by discharging the corresponding pair of output nodes via a discharging FET pair connected to the pair of common nodes, the FET pair receiving the sampling interval signal and selectively enabling the differential current to discharge the corresponding pair of output nodes, and latching the differential output voltage.

Abstract: Methods and systems are described for generating, with a local oscillator and an adjustable phase interpolator, a data-sampling clock and a variable-phase-offset eye-measurement clock, forming a received data signal using a multi-input comparator, generating, using a data slicer and the data sampling clock, a receive sample of the received data signal, and generating, using at least one eye slicer and the variable-phase-offset eye-measurement clock, a plurality of eye characteristic measurements by adjusting a sampling threshold of the at least one eye slicer and a phase offset of the variable-phase-offset eye-measurement clock.

Abstract: Transmission of baseband and carrier-modulated vector codewords, using a plurality of encoders, each encoder configured to receive information bits and to generate a set of baseband-encoded symbols representing a vector codeword; one or more modulation circuits, each modulation circuit configured to operate on a corresponding set of baseband-encoded symbols, and using a respective unique carrier frequency, to generate a set of carrier-modulated encoded symbols; and, a summation circuit configured to generate a set of wire-specific outputs, each wire-specific output representing a sum of respective symbols of the carrier-modulated encoded symbols and at least one set of baseband-encoded symbols.

Abstract: Methods and systems are described for receiving an input data voltage signal at a first data decision circuit of set of pipelined data decision circuits, receiving an aggregate decision feedback equalization (DFE) correction current signal from a first analog current summation bus, the aggregate DFE correction current signal comprising a plurality of DFE tap-weighted currents from respective other data decision circuits of the set of pipelined data decision circuits, determining a data output decision value based on the received input data voltage signal and the received aggregate DFE correction current signal, and generating at least one outbound DFE tap-weighted current on at least one other analog current summation bus connected to at least one other data decision circuit of the set of pipelined data decision circuits.

Abstract: Methods and systems are described for receiving N phases of a local clock signal and M phases of a reference signal, wherein M is an integer greater than or equal to 1 and N is an integer greater than or equal to 2, generating a plurality of partial phase error signals, each partial phase error signal formed at least in part by comparing (i) a respective phase of the M phases of the reference signal to (ii) a respective phase of the N phases of the local clock signal, and generating a composite phase error signal by summing the plurality of partial phase error signals, and responsively adjusting a fixed phase of a local oscillator using the composite phase error signal.

Abstract: Methods and systems are described for receiving a reference clock signal and a phase of a local oscillator signal at a dynamically-weighted XOR gate comprising a plurality of logic branches, generating a plurality of weighted segments of a phase-error signal, the plurality of weighted segments including positive weighted segments and negative weighted segments, each weighted segment of the phase-error signal having a respective weight applied by a corresponding logic branch of the plurality of logic branches, generating an aggregate control signal based on an aggregation of the weighted segments of the phase-error signal, and outputting the aggregate control signal as a current-mode output for controlling a local oscillator generating the phase of the local oscillator signal, the local oscillator configured to induce a phase offset into the local oscillator signal in response to the aggregate control signal.

Abstract: Methods and systems are described for receiving, over a plurality of consecutive signaling intervals, a plurality of codewords, each codeword received as a plurality of symbols via wires of a multi-wire bus, the plurality of symbols received at a plurality of multi-input comparators (MICs), wherein each symbol is received by at least two MICs, generating, for each codeword, a corresponding linear combination of the received symbols, generating a plurality of composite skew measurement signals over the plurality of consecutive signaling intervals, each composite skew measurement signal based on samples of one or more linear combinations, and updating wire-specific skew values of the wires of the multi-wire bus, wherein one or more wire-specific skew values are updated according to composite skew measurement signals associated with linear combinations formed by at least two different MICs.

Abstract: Methods and systems are described for receiving a sampling signal, pre-charging a pair of output nodes prior to a sampling interval, initiating the sampling interval by enabling a current source according to a first transition of the received sampling signal, generating a differential output voltage at the pair of output nodes by discharging the pair of output nodes according to a differential input signal, the pair of output nodes discharged according to current drawn by the current source during the sampling interval, terminating the sampling interval by disabling the current source in response to a second transition of the received sampling signal, and inhibiting a recharge of the pair of output nodes for a hold time after termination of the sampling interval and prior to initiation of a subsequent sampling interval.

Abstract: Methods and systems are described for generating, using a voltage-controlled oscillator (VCO), a plurality of phases of a local clock signal, generating a phase-error signal using a phase comparator receive a phase of the local clock signal and a reference clock signal, and configured to output the phase-error signal, generating a frequency-lock assist (FLA) signal using a FLA circuit receiving one or more phases of the local clock signal and the reference clock signal, the FLA signal indicative of a magnitude of a frequency error between the reference clock signal and the local clock signal, and generating a VCO control signal using an error accumulator circuit receiving the phase-error signal and the FLA signal, and responsively providing the VCO control signal to the VCO to lock the local clock signal to the reference clock signal.