H04L25/03057

High speed communications system

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.

Hardware efficient decision feedback equalization training

Disclosed is an improved approach for a training approach to implement DFE for an electronic circuit. The inventive concept is particularity suitable to address, for example, circuits that implement high speed parallel data transmission protocols, such as GDDR6, that are used for graphics applications. The training scheme uses minimal hardware when compared to existing schemes by reusing calibration receiver in auto zeroing receiver as error receiver. Further it works for closed eyes by running the algorithm multiple times with gradual increase in complexity of training pattern, where DFE coefficients from previous iteration is used for the current iteration, thereby gradually opening the eye.

Clock extraction in systems affected by strong intersymbol interference
11637684 · 2023-04-25 · ·

A timing recovery apparatus for signal reception in a data transmission system comprises an equalizer to equalize a received signal and a phase detector connected after the timing recovery equalizer that generates a clock tone from absolute values of the received signal after equalization.

Receiver synchronization

A receiver circuit includes a feedback loop including a device. The receiver circuit also includes a register and a sequencer. The sequencer is configured to, responsive to an error signal being below a threshold value, cause the register to store a value indicative of the state of the feedback loop. The sequencer is also configured to cause the feedback loop to transition to a lower power state, and, responsive to a detected wake-up event, cause the previously stored value indicative of the state of the feedback loop to be loaded from the register into the device and enable the feedback loop.

Quarter rate speculative decision feedback equalizer (DFE) and method for operating thereof

Accordingly embodiments herein disclose a quarter rate speculative DFE. The quarter rate speculative DFE includes a plurality of sampler circuits connected to an input terminal. The plurality of sampler circuits are configured to sample an input signal into a plurality of data samples in parallel. A plurality of quarter rate look ahead circuit connected to the plurality of sampler circuits. The plurality of quarter rate look ahead circuit is configured to simultaneously perform an align operation and a look ahead operation on the plurality of data samples based on the different clock phases to obtain a plurality of latched outputs. A plurality of multiplexers connected to the plurality of quarter rate look ahead circuit. The plurality of multiplexers is configured to generate two speculative data streams by multiplexing respective correction coefficients of each of the plurality of latched outputs.

Multi-stage continuous time linear equalizer with reconfigurable inductor scheme
11601309 · 2023-03-07 · ·

A multi-stage continuous time linear equalizer (CTLE) with a reconfigurable inductor scheme is disclosed. The multi-stage CTLE comprises a first stage transformer-based inductive peaking and a second stage resistive load. The first stage transformer-based inductive peaking is configured to control high frequency peaking and set a peak frequency value to a desired value by using a coarse equalization mechanism. The stage resistive load configured to provide tuneable equalization and low frequency fine equalization by using a fine equalization mechanism.

HIGH SPEED COMMUNICATIONS SYSTEM
20230068176 · 2023-03-02 ·

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.

ERROR SAMPLER CIRCUIT

An error sampler circuit includes a differential input voltage input, a differential reference voltage input, a master latch circuit, and a slave latch circuit. The master latch circuit includes a slicer circuit. The slicer circuit includes a first input, a second input, and a differential output. The first input is coupled to the differential input voltage input. The second input is coupled to the differential reference voltage input. The slave latch includes a differential input coupled to the differential output of the slicer circuit.

PHASE INTERPOLATOR CIRCUITRY FOR A BIT-LEVEL MODE RETIMER
20230122556 · 2023-04-20 · ·

Disclosed are some examples of Phase interpolator circuitry used in retimer systems. The phase interpolator circuitry includes a phase interpolator configured to: receive the phase control signal, generate, based on the phase control signal, an output clock signal, and provide the output clock signal to the transmitter to track a plurality data packets. Phase interpolator circuitry is coupled with clock data recovery circuitry. In some implementations, clock data recovery circuitry is coupled between a receiver and a transmitter. The clock data recovery circuitry is configured to: extract a data component from an input data signal associated with the receiver, provide the data component to the transmitter, and generate a phase control signal.

SEQUENCE DETECTION DEVICE USING PATH-SELECTIVE SEQUENCE DETECTION AND ASSOCIATED SEQUENCE DETECTION METHOD
20230118769 · 2023-04-20 · ·

A sequence detection device includes a decision-feedback equalizer (DFE), a combining circuit, a decision circuit, and a sequence detection circuit. The DFE processes a symbol decision signal to generate a first equalized signal. The combining circuit combines a data signal and the first equalized signal to generate a sample signal. The decision circuit performs hard decision upon the sample signal to generate the symbol decision signal. The sequence detection circuit performs sequence detection upon the data signal to generate and output a symbol sequence. Regarding the sequence detection, the sequence detection circuit selects branches for branch metric calculation according to at least the symbol decision signal.