H03M1/1215

Methods, systems and apparatus for hybrid signal processing for pulse amplitude modulation

A method to implement hybrid signal processing includes steps for receiving an analog signal at a receiver frontend, sampling the received analog signal and storing the analog sampled signals using a plurality of sampling circuitries inside the receiver frontend. Then, processing the plurality of analog sampled signals using interleaved feed-forward equalizers (FFEs) to provide FFE interleaved sampled signal values corresponding to each of the sampling circuitries. Then, processing the analog sampled signals at an interleaved Decision Feedback Equalizer (DFE) to obtain DFE interleaved sampled signal values, summing each of the FFE interleaved sampled signal values with output from one of the DFE interleaved sampled signal values to provide equalizer output signal values, and digitizing the equalizer output signal values to provide digital data bits corresponding to each of the equalizer output signal values. Implementations of the method as a hybrid communication system, system-on-a-chip, and computer readable memory are also disclosed.

ANALOG-TO-DIGITAL CONVERSION CIRCUIT AND RECEIVER INCLUDING SAME

An analog-to-digital conversion circuit includes analog-to-digital converters (ADCs) including a target analog-to-digital converter (ADC) providing second data samples, a first adjacent ADC providing first data samples, and a second adjacent ADC providing third data samples. The ADCs perform an analog-to-digital conversion using a time-interleaving approach in response to clock signals having different phases and including a reference clock signal. A timing calibration circuit includes a relative time skew generator generating a relative time skew and an absolute time skew generator generate an absolute time skew. A clock generator adjusts at least one phase of the clock signals based on the absolute time skew.

Dynamic integration time adjustment of a clocked data sampler using a static analog calibration circuit

Methods and systems are described for generating a process-voltage-temperature (PVT)-dependent reference voltage at a reference branch circuit based on a reference current obtained via a band gap generator and a common mode voltage input, generating a PVT-dependent output voltage at an output of a static analog calibration circuit responsive to the common mode voltage input and an adjustable current, adjusting the adjustable current through the static analog calibration circuit according to a control signal generated responsive to comparisons of the PVT-dependent output voltage to the PVT-dependent reference voltage, and configuring a clocked data sampler with a PVT-calibrated current by providing the control signal to the clocked data sampler.

BAND-PASS ANALOG-TO-DIGITAL CONVERTER USING BIDIRECTIONAL VOLTAGE-CONTROLLED OSCILLATOR
20220376697 · 2022-11-24 ·

The present disclosure discloses a band-pass analog-to-digital converter (ADC) using a bidirectional voltage-controlled oscillator (VCO) including a first converter configured to receive an analog input signal and quantize the analog input signal according to a first clock signal to output a first digital signal, a second converter configured to receive the analog input signal and quantize the analog input signal in a time-interleaving manner according to a second clock signal, which has a phase opposite to that of the first clock signal, to output a second digital signal, and a multiplexer configured to receive the first and second digital signals and select one of the two signals in response to the first clock signal to finally output a digital output signal.

TIMING SKEW MISMATCH CALIBRATION FOR TIME INTERLEAVED ANALOG TO DIGITAL CONVERTERS

A time-interleaved analog to digital converter (TI-ADC) includes a first sub-ADC configured to sample and convert an input analog signal to generate a first digital signal and a second sub-ADC configured to sample and convert said input analog signal to generate a second digital signal. Sampling by the second sub-ADC occurs with a time skew mismatch. A multiplexor interleaves the first and second digital signals to generate a third digital signal. A time skew mismatch error determination circuit processes the first and second digital signals to generate a time error corresponding to the time skew mismatch. A slope value of said third digital signal is determined and multiplied by the time error to generate a signal error. The signal error is summed with the third digital signal to generate a digital output signal which eliminates the error due to the time skew mismatch. This correction is performed in real time.

LINEARITY AND/OR GAIN IN MIXED-SIGNAL CIRCUITRY
20230034555 · 2023-02-02 ·

Mixed-signal circuitry including a set of capacitive digital-to-analogue converter, CDAC, units for carrying out digital-to-analogue conversion operations to convert respective digital values into corresponding analogue values; and control circuitry, where: each CDAC unit includes an array of capacitors at least some of which are configured to be individually-switched dependent on the digital values, the capacitors configured to have nominal capacitances; a given capacitor of the array of capacitors in each of the CDAC units is a target capacitor; the set of CDAC units includes a plurality of sub-sets of CDAC units; at least one of the target capacitors per sub-set of CDAC units is a variable capacitor, controllable by the control circuitry to have any one of a plurality of nominal capacitances defined by the configuration of that capacitor.

SPECTRAL CONTENT DETECTION FOR EQUALIZING INTERLEAVED DATA PATHS

A high-speed data receiver includes interleaver circuitry configured to divide a received data stream into a plurality of interleaved paths for processing, spectral content detection circuitry configured to derive spectral content information from data on each of the plurality of interleaved paths, sorting circuitry configured to bin the derived spectral content information according to energy levels, stream attribute determination circuitry configured to determine, based on sorted spectral content, one or more of path offsets of the interleaved paths, gain mismatch among interleaved paths, signal bandwidth mismatch and pulse width mismatch, and equalization circuitry configured to correct the one or more of the determined offsets, the determined gain mismatch and the determined signal width mismatch. Equalization circuitry may be configured to equalize a gain-normalized signal by separately adjusting respective bandwidth actuators of each respective interleaved path and respective pulse width actuators of each respective interleaved path.

ANALOG-TO-DIGITAL CONVERTOR PSEUDO PERIODIC IL ESTIMATION

Aspects of the description provide for an analog-to-digital converter (ADC) operable to convert an analog input signal to an output signal at an output of the ADC. In some examples, the ADC includes multiple sub-ADCs coupled in parallel, each of the multiple sub-ADCs coupled to the output of the ADC and operable to receive the analog input signal. The ADC is configured to operate the sub-ADCs in a consecutive operation loop including a transition phase in which the ADC operates each of the sub-ADCs sequentially for a first number of sequences, an estimation phase in which the ADC operates each of the sub-ADCs sequentially for a second number of sequences following the first number of sequences, and a randomization phase in which the ADC operates subsets of the sub-ADCs for a third number of sequences following the second number of sequences.

Successive-approximation-register (SAR) analog-to-digital converter (ADC) timing calibration
11616511 · 2023-03-28 · ·

An analog-to-digital converter (ADC) is described. This ADC includes a conversion circuit with multiple bit-conversion circuits. During operation, the ADC may receive an input signal. Then, the conversion circuit may asynchronously perform successive-approximation-register (SAR) analog-to-digital conversion of the input signal using the bit-conversion circuits, where the bit-conversion circuits to provide a quantized representation of the input signal. For example, the bit-conversion circuits may asynchronously and sequentially perform the SAR analog-to-digital conversion to determine different bits in the quantized representation of the input signal. Moreover, the ADC may selectively perform self-calibration of a global delay of the bit-conversions circuits. Note that the timing self-calibration may be iterative and subject to a constraint that a maximum conversion time is less than a target conversion time.

Analog-to-digital conversion
11489538 · 2022-11-01 · ·

A circuit having an array of Analog-to-Digital Converters (ADCs); a sampling order selector configured to select a sampling order of the ADCs and output corresponding sampling order control words; sampling pulse generators coupled between the sampling order selector and the respective ADCs, and configured to output respective sampling pulses based on the respective sampling order control words, wherein the ADCs are configured to sample and convert analog data into digital data in response to the sampling pulses; and a single clock generator configured to distribute a delay-matched clock to each of the ADCs in parallel, to each of the sampling pulse generators in parallel, and to the sampling order selector.