A Successive Approximation Register, SAR, Analog to Digital Converter, ADC, (50) achieves high speed and accuracy by (1) alternating at least some decisions between sets of comparators having different accuracy and noise characteristics, and (2) unevenly allocating redundancy (in the form of LSBs of range) for successive decisions according to the accuracy/noise of the comparator used for the preceding decision. The redundancy allocation is compensated by the addition of decision cycles. Alternating between different comparators removes the comparator reset time (treset) from the critical path, at least for those decision cycles. The uneven allocation of redundancy—specifically, allocating more redundancy to decision cycles immediately following the use of a lower accuracy/higher noise comparators—compensates for the lower accuracy and prevents the need for larger redundancy (relative to the full-scale range of a decision cycle) later in the ADC process.

Systems and methods for an asynchronous successive approximation register analog-to-digital converter (SAR ADC) with word completion algorithm may include a SAR ADC comprising a plurality of switched capacitors, a comparator, a metastability detector including a timer having a tunable time interval, and a successive approximation register. The SAR ADC may sample input signals at inputs of the switched capacitors and compare signals at outputs of the switched capacitors. The SAR ADC may also determine, based on a value of a tunable time interval, whether to set a metastability flag for a first bit to be evaluated and update the value of the tunable time interval based on whether the metastability flag was set.

An analog-to-digital converter includes a voltage-controlled oscillator (VCO) having an input for receiving an analog input signal; a double binary counter having a first input coupled to a first output of the VCO, a second input coupled to a second output of the VCO; a first set of registers coupled to the first output of the double binary counter; a second set of registers coupled to the second output of the double binary counter; sense amplifiers coupled to the outputs of the VCO; and a correction component coupled to the first set of registers, the second set of registers, and the sense amplifiers, wherein the correction component generates a coarse count, a fine count, and combines the coarse count and the fine count to provide a digital output signal representative of the analog input signal.

This invention relates to multichannel signal processing systems using synchronous protocols I2S (Inter-IC Sound Bus) and SPI (Serial Peripheral Bus) for sequenced data exchange, and providing unified synchronization of processed data. The system and method for synchronously multiplexing data streams in the I2S or SPI formats involves transformation of a standard Left/Right Clock (LRCK) sampled pulse signal of the I2S format or a Chip Select (CS) pulse signal of the SPI format into a LRCLt signal comprising a time stamp code and start and end marker codes of the synchronization clock signal, LRCK or CS, respectively. The presence of the marker codes and the time stamp code enables to restore the pulse signal, LRCK or CS, respectively, in the process of data stream program processing and link each discrete sample to the time stamp. The digital stream multiplexing system includes m channel groups for collection of synchronous data in the I2S or SPI synchronous protocol, a clock generator, a host processor and a means of transforming the LRCK or CS signal into the LRCKt signal. The technical effect consists in removal of limitations on a number of fully synchronized data streams in the I2S or SPI formats and, at the same time, simplification of the synchronization system and method and reduction in requirements to hardware resources.

An analog-to-digital converter according to one or more embodiments is disclosed that converts an analog input to a digital converted value by repeating a conversion data generation operation by a conversion data generator, a potential generation operation by a capacitance DAC, and a comparison operation by a comparator for a resolution bit, the analog-to-digital converter. a comparator operation signal generation circuit predicts the time when a potential generated by the capacitance DAC becomes settled based on a charging or discharging time to a capacitance element whose characteristics are equal to those of the capacitance used in the capacitance DAC, and generates a comparator operation signal to allow the comparator to start the comparison operation.

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.

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 disclosure belongs to the technical field of analog or digital-analog hybrid integrated circuits, and relates to a high-speed SAR_ADC digital logic circuit, in particular to a high-speed digital logic circuit for SAR_ADC and a sampling adjustment method. The digital logic circuit includes a comparator, a logic control unit parallel to the comparator, and a capacitor array DAC. The comparator and the logic control unit are simultaneously triggered by a clock signal. The comparator outputs a valid comparison result Dp/Dn, the logic control unit outputs a corresponding rising edge signal, the rising edge signal is slightly later than Dp/Dn output by the comparator through setting a delay match, Dp/Dn is captured by the corresponding rising edge signal, thereby settling a capacitor array. The present disclosure eliminates the disadvantage of the improper settling of the capacitor array of the traditional parallel digital logic.

A pipeline analog to digital converter (ADC) includes converter circuitries, a detector circuitry, and a clock generator circuit. The converter circuitries sequentially convert an input signal to be digital codes. One of the converter circuitries includes a sub-ADC circuit and a multiplying digital to analog converter (MDAC) circuit. The sub-ADC circuit performs a quantization according to a first signal to generate a corresponding one of the digital codes, in which the first signal is the input signal or a previous stage residue signal. The MDAC circuit processes the corresponding one of the digital codes in response to a first clock signal, in order to generate a current stage residue signal. The detector circuitry detects whether the quantization is complete, in order to generate a control signal. The clock generator circuit adjusts a timing of the first clock signal according to the control signal.

A pipeline analog to digital converter includes converter circuitries and a calibration circuitry. The converter circuitries sequentially convert an input signal into first digital codes. A first converter circuitry in the converter circuitries performs a quantization according to a first signal to generate a first corresponding digital code in the first digital codes, and the first signal is a signal, which is processed by the first converter circuitry, of the input signal and a previous stage residue signal. The calibration circuitry combines the first digital codes to output a second digital code, detects whether the quantization is completed to generate first and second valid signals, and determines whether to set the second digital code to be a first predetermined digital code or a second predetermined digital code according to the first and the second valid signals. The second valid signal is a delay signal of the first valid signal.