A N-bit continuous-time sigma-delta modulator, SDM, (800) includes an input configured to receive an input analog signal (302); a first summing junction (304) configured to subtract a feedback analog signal (303) from the input analog signal (302); a loop filter (306) configured to filter an output signal from the first summing junction (304): an N-bit analog-to-digital converter, ADC, comprising at least one 1-bit ADC configured to convert the filtered analog output signal (309) to a digital output signal (314) where each 1-bit ADC comprises at least one pair of comparator latches (336, 356); and a feedback path (316) for routing the digital output signal to the first summing junction (304). The feedback path (316) includes a plurality of digital-to-analog converters, DACs, configured to convert the digital output signal (314) to an analog form. The ADC comprises or is operably coupled to, a calibration circuit (650, 840) coupled to an input and an output of the at least one pair of comparator latches (336, 356) and configured to apply respective calibration signals to individual comparator latches of the at least one pair of comparator latches (336, 356) in a time-Interleaved manner, and calibrate a comparator error of the comparator latches in response to a latched output of the respective calibration signals.

A digital-to-analog conversion system is provided. The digital-to-analog conversion system includes a digital-to-analog converter configured to receive a pre-distorted digital signal from a digital circuit, and to generate an analog signal based on the pre-distorted digital signal. Further, the digital-to-analog conversion system includes a feedback loop for providing a digital feedback signal to the digital circuit. The feedback loop includes an analog-to-digital converter configured to generate the digital feedback signal based on the analog signal, and wherein a sample rate of the analog-to-digital converter is lower than a sample rate of the digital-to-analog converter.

It is provided a provided a time-interleaved analog-to-digital converter (ADC) system comprising an input port configured to receive an analog signal, an ADC-array comprising M, M2, ADCs arranged in parallel. Each ADC is configured to receive and to convert a portion of the analog signal into a digital signal at a sample rate f.sub.s. The ADC-system further comprises a reference ADC configured to receive and to convert the analog signal into a digital reference signal at an average sampling rate f.sub.ref lower than f.sub.s. Each sampling instant of the reference ADC corresponds to a sampling instant of an ADC in the array of ADCs, and the ADC to select for each reference ADC sampling instant is randomized over time. The ADC-system also comprises a correction module configured to adjust the digital signal outputs of the ADC-array into a corrected digital output signal based on samples of the digital reference signal and the digital signals from the corresponding selected ADCs. It is also provided a method for time-interleaved analog-to-digital conversion.

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.

Analog-to-digital converter (ADC) circuitry to convert an analog signal to a digital signal is disclosed herein. The ADC circuitry can utilize pipelined-interpolation analog-to-digital converters (PIADCs) with adaptation circuitry to correct regenerative amplification cells of the PIADCs. The PIADCs can implement a rotational shuffling scheme for correction of the regenerative amplification cells, where the correction implemented by the regenerative amplification cells allows for offsetting of latches of the regenerative amplification cells.

A digital to time converter (DTC) system is disclosed. The DTC system comprises a DTC circuit configured to generate a DTC output clock signal at a DTC output frequency, based on a DTC code. In some embodiments, the DTC system further comprises a calibration circuit comprising a period error determination circuit configured to determine a plurality of period errors respectively associated with a plurality consecutive edges of the DTC output clock signal. In some embodiments, each period error of the plurality of period errors comprises a difference in a measured time period between two consecutive edges of the DTC output clock signal from a predefined time period. In some embodiments, the calibration circuit further comprises an integral non-linearity (INL) correction circuit configured to determine a correction to be applied to the DTC code based on a subset of the determined period errors.

There provided an AD converter that includes an analog processing part configured to select one of the measurement target voltages and a plurality of reference voltages for each channel, to output an analog voltage signal; a first selection part configured to select one of a plurality of analog voltage signals; a first AD conversion part configured to perform AD conversion on the analog voltage signal to generate a first original digital signal; a second selection part configured to select one of the plurality of analog voltage signals; a second AD conversion part configured to perform AD conversion on the analog voltage signal to generate a second original digital signal; a digital processing part configured to receive the first original digital signal and the second original digital signal; and a controller configured to control contents selected in the analog processing part, the first selection part, and the second selection part.

A digital-to-analog conversion system is provided. The digital-to-analog conversion system includes a digital-to-analog converter configured to receive a pre-distorted digital signal from a digital circuit, and to generate an analog signal based on the pre-distorted digital signal. Further, the digital-to-analog conversion system includes a feedback loop for providing a digital feedback signal to the digital circuit. The feedback loop includes an analog-to-digital converter configured to generate the digital feedback signal based on the analog signal, and wherein a sample rate of the analog-to-digital converter is lower than a sample rate of the digital-to-analog converter.

In accordance with various embodiments of the disclosed subject matter, a system, device, apparatus and method for calibrating a split bit digital readout to avoid misalignment of the least significant counter bit (i.e., the LSB of the M most significant bits) and most significant residual bit (i.e. the MSB of the N least significant bits). For example, various embodiments provide a field programmable gate array (FPGA), digital signal processing (DSP) function and the like configured to calibrate one or many split bit digital readouts such as may exist on a digital pixel sensor (DPS) or other device.

There provided an AD converter that includes an analog processing part configured to select one of the measurement target voltages and a plurality of reference voltages for each channel, to output an analog voltage signal; a first selection part configured to select one of a plurality of analog voltage signals; a first AD conversion part configured to perform AD conversion on the analog voltage signal to generate a first original digital signal; a second selection part configured to select one of the plurality of analog voltage signals; a second AD conversion part configured to perform AD conversion on the analog voltage signal to generate a second original digital signal; a digital processing part configured to receive the first original digital signal and the second original digital signal; and a controller configured to control contents selected in the analog processing part, the first selection part, and the second selection part.