A device includes a first compensation circuit configured to adjust an analog front end (AFE) output to generate a first adjusted AFE output, a first data slicer configured to output a first voltage based on the first adjusted AFE output. The first compensation circuit includes a first path between a voltage source and a ground, including a first transistor, a first adjustable current source, a first input voltage node configured to receive the AFE output, and a first output voltage node coupled to the first data slicer, a second path between the voltage source and the ground, including a second transistor, a second adjustable current source, a second input voltage node configured to receive the AFE output, and a second output voltage node coupled to the second data slicer, and a configurable resistance resistor and a configurable capacitance capacitor coupled in parallel across the first path and the second path.

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.

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.

Methods and apparatus for adaptively generating a reference voltage (V.sub.REF) for biasing a switch driver and corresponding switch in a digital-to-analog converter (DAC). The adaptive biasing scheme may be capable of tracking process, voltage, and temperature (PVT) of the DAC. An example DAC generally includes a plurality of DAC cells, each DAC cell comprising a current source, a switch coupled in series with the current source, and a switch driver coupled to a control input of the switch, the switch driver being configured to receive power from a first power supply rail referenced to a reference potential node; a regulation circuit comprising a first transistor coupled between the reference potential node for the DAC and the switch driver in at least one of the plurality of DAC cells; and a V.sub.REF generation circuit coupled to the regulation circuit and configured to adaptively generate a V.sub.REF for the regulation circuit.

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.

An analog-to-digital converter (ADC) circuit comprises one or more most-significant-bit (MSB) capacitors having first ends connected to a voltage comparator and one or more least-significant-bit (LSB) capacitors having first ends connected to the comparator. The circuit further comprises a first switching circuit for each MSB capacitor, configured to selectively connect the second end of the respective MSB capacitor to (a) an input voltage, for sampling, (b) a ground reference, during portions of a conversion phase, and (c) a first conversion reference voltage, for other portions of the conversion phase. The circuit still further comprises a second switch circuit, for each LSB capacitor, configured to selectively connect the second end of the respective LSB capacitor between (d) the ground reference, during portions of the conversion phase, and (e) a second conversion reference voltage, for other portions of the conversion phase, the second conversion reference voltage differing from the first.

An apparatus configured to convert an analog input signal into a digital output signal may include a first amplification circuit configured to receive the analog input signal and a plurality of reference voltages and amplify differences between the analog input signal and the plurality of reference voltages; a plurality of first capacitors configured to respectively store charges corresponding to signals outputted by the first amplification circuit; a second amplification circuit configured to amplify differences among voltages of the plurality of first capacitors; a plurality of second capacitors configured to respectively store charges corresponding to signals outputted by the second amplification circuit; and a comparison circuit configured to generate the digital output signal by comparing voltages of the plurality of second capacitors with each other.

An ADC includes a plurality of sub ADCs configured to operate in a time-interleaved manner and a sampling circuit configured to receive an analog input signal of the ADC, wherein the sampling circuit is common to all sub ADCs. The ADC includes a test signal generation circuit configured to generate a test signal for calibration of the ADC. The sampling circuit has a first input configured to receive the analog input signal and a second input configured to receive the test signal. The sampling circuit includes an amplifier circuit and a first feedback switch connected between an output of the amplifier circuit and an input of the amplifier circuit. The first feedback switch is configured to be closed during a first clock phase and open during a second clock phase, which is non-overlapping with the first clock phase.

A successive-approximation analog-to-digital converter includes a sampling circuit for sampling an analog input signal to acquire a sampled voltage, and a regenerative comparator for comparing the sampled voltage with a succession of reference voltages to generate, for each reference voltage, a decision bit indicating the comparison result. The converter also includes a digital-to-analog converter which is adapted to generate the succession of reference voltages, in dependence on successive comparison results in the comparator, to progressively approximate the sampled voltage. The regenerative comparator comprises an integration circuit for generating output signals defining the decision bits, and a plurality of regeneration circuits for receiving these output signals. The regeneration circuits are operable, in response to respective control signals, to store respective decision bits defined by successive output signals from the integration circuit.

The present invention discloses a DAC method having signal calibration mechanism. A first conversion circuit generates a first analog signal according to an input digital signal. A second conversion circuit generates a second analog signal according to the input digital signal and a pseudo-noise digital signal. An echo transmission circuit processes a signal on an echo path to generate an echo signal. A first and a second calibration circuits generate a first and a second calibration signals. A calibration parameter calculation circuit performs calculation according to a difference between the echo signal and a sum of the first and the second calibration signals and related path information to generate a first and a second offsets. The first and the second calibration circuits converge first and second response coefficients and update a first and a second codeword offset tables according to the first and the second offsets.