Patent classifications
H03M1/0836
Semiconductor integrated circuit and receiver device
A semiconductor integrated circuit includes a converter converting an analog signal into a digital signal based on a clock signal; a comparator determining values of data based on the digital signal; a recovery circuit recovering the clock signal based on the digital signal and the data; and a control circuit. The recovery circuit includes a phase detector calculating a sum of a first value and offset, the first value being a value based on the digital signal and the data and relating to a phase of the clock signal; and a loop filter calculating a correction amount of the phase of the clock signal based on the sum. The control circuit is configured to gradually change the offset from a second value to zero after the second value is added as the offset.
CALIBRATION METHOD, CALIBRATION APPARATUS, TIME-INTERLEAVED ADC, ELECTRONIC DEVICE, AND READABLE MEDIUM
The present disclosure relates to communication devices and provides a method and apparatus for calibrating a sampling timing skew between time-interleaved analog to digital converter (ADC) channels, a time-interleaved ADC, an electronic device, and a computer readable medium. The time-interleaved ADC includes multiple ADC channels. The method includes: calculating, for every two adjacent channels, a correlation value between digital signals of two adjacent channels, according to the digital signals output by every two adjacent channels; calculating a timing skew adjustment amount corresponding to a sampling timing skew of each of the channels relative to a reference channel according to the correlation value corresponding to every two adjacent channels, the reference channel being any designated channel among the plurality of channels; and calibrating the sampling timing skew of each of the channels relative to the reference channel according to the timing skew adjustment amount corresponding to each of the channels.
INTEGRATED TIMING SKEW CALIBRATION WITH DIGITAL DOWN CONVERSION FOR TIME-INTERLEAVED ANALOG-TO-DIGITAL CONVERTER
An interleaved analog-to-digital conversion (ADC) system may have timing errors in a time domain that is corrected using phase compensation in a phase domain. The ADC system may include sub-ADCs, each receiving a clock signal, which is associated with a representation of a timing skew value, reflecting an undesired timing error. A mixer may have sub-mixers, each receiving a sub-ADC output signal and a compensated numerically controlled oscillator (NCO) value. A combiner may combine the sub-mixer output signals. A decimator may decimate the output of the combiner. Each timing skew value is in a time domain. A compensated NCO value is determined using a respective phase skew value. Each phase skew value is an offset value in phase and is not a value in time. Each phase skew value in a phase domain compensates the respective timing skew value in a time domain. Multiple ADC systems and methods are described.
DUAL-CLOCK GENERATION CIRCUIT AND METHOD AND ELECTRONIC DEVICE
The present disclosure relates to a dual-clock generation circuit and method and an electronic device, and relates to the technical field of integrated circuits. The dual-clock generation circuit includes: a first inverter module, configured to access a first signal and output a first clock output signal; a second inverter module, configured to access a second signal and output a second clock output signal, where the first signal and the second signal are opposite clock signals; a first feedforward buffer, disposed between an input terminal of the first inverter module and an output terminal of the second inverter module, and configured to transmit the first signal to compensate for the second clock 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.
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.
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.
Digital-to-analog conversion architecture and method
Digital-to-analog converter (DAC) architecture, comprising: a matrix DAC array comprising a plurality of cells arranged in a first dimension and a second dimension, each cell comprising a local decoder configured to transition the cell between at least two states; and decoding circuitry configured to: receive a digital input signal; and control the plurality of local decoders based on a received digital input signal, wherein each incremental change in the digital input signal results in a transition of a single cell of the plurality of cells such that the plurality of cells transition in sequence, the sequence of transitions of the plurality of cells defining a path through the DAC array; wherein when the path proceeds in the first dimension, the path proceeds to an adjacent cell of the plurality of cells at least 50% of the time; and wherein when the path proceeds in the second dimension, the path proceeds to an adjacent cell of the plurality of cells at least 50% of the time.
REDUCING SPURS IN ANALOG TO DIGITAL AND DIGITAL TO ANALOG CONVERSIONS
Embodiments disclosed herein may reduce or even eliminate spurs introduced into the signals during analog to digital or digital to analog conversions. The spurs may be introduced by components such as clocks of the converter circuits. In an analog to digital conversion, the input signal may be split into two parts: the first portion passing through a first analog to digital converter (ADC) and an inverted second portion passing through a second ADC. A digital subtractor may subtract the output of the second ADC from the output of the first ADC converter thereby reducing the spurs. In digital to analog conversion, a digital input is passed through a first digital to analog converter (DAC) and an inverted digital input is passed through a second DAC. The output of the second DAC is inverted and combined with the output of the first DAC to reduce the spurs.
ANALOG TO DIGITAL CONVERTER DEVICE AND METHOD FOR CONTROLLING CALIBRATION CIRCUIT
An analog to digital converter (ADC) device includes ADC circuits, a calibration circuit and a controlling circuit. The ADC circuits are configured to generate first quantized outputs according to clock signals. The calibration circuit is configured to perform at least one error operation according to the first quantized outputs to generate second quantized outputs, and is configured to analyze time difference information of the clock signals according to the second quantized outputs to generate adjustment signals. The controlling circuit is configured to analyze the first quantized outputs to generate at least one control signal to the calibration circuit, wherein the at least one control signal is configured to control the calibration circuit to selectively perform the at least one error operation and selectively analyze the time difference information of the clock signals.