In accordance with an embodiment, a method includes adding a dither signal to a first signal to generate a second signal, subtracting the dither signal from the first signal or subtracting the first signal from the dither signal to generate a third signal, performing a first sigma delta conversion of the second signal to a digital fourth signal, performing a second signal delta conversion of the third signal to a digital fifth signal, combining the digital fourth signal and the digital fifth signal to form a digital sixth signal.

A method and system for data conversion includes an analog noise generator to generate a random, non-deterministic, analog noise signal. An adder adds the analog noise signal to an analog RF signal to produce a dithered analog signal. A first quantizer converts the analog noise signal to digital to produce a digital noise signal. A second quantizer converts the dithered analog signal to a digital equivalent signal. A digital dither adjustment module removes amplitude measurements of the digital noise signal from the digital equivalent signal to obtain a linearized digital representation of the analog RF signal.

A low-pass and band-pass delta-sigma (??) analog-to-digital converter (ADC) device for sensor interface is disclosed. The device includes a first stage comprising a low-resolution passive integrator-based noise-shaping successive approximation register (SAR) ADC and a second stage comprising a voltage-controlled oscillator (VCO)-ADC.

An apparatus for measuring a measured variable, wherein a first inductance and at least one measurement inductance are coupled, and wherein dithering is used to increase accuracy.

A system includes a dither generator module that includes a most significant bits (MSB) dither generator device that generates a first random value. The dither generator module also includes a least significant bits (LSB) dither generator device that generates a second random value. The system further includes a first digital to analog converter (DAC) that receives a sum of the first random value and the second random value and generates a dither signal based on the sum of the first random value and the second random value. The system also includes an analog to digital converter (ADC) that receives a sum of the dither signal and a sampled input signal and generates a first digitized signal. The system includes a subtraction module that subtracts the sum of the first random value and the second random value from the first digitized signal to produce a digitized output signal.

A device for digitizing an analog signal, wherein a distortion signal outlet of a distortion signal generator is only coupled to an analog digital converter by passive components.

CT ADCs based on continuous-time residue generation systems require accurate estimation of analog transfer functions. This is done by using a pseudo random bit sequence, injected using a DAC, that traverses the transfer function to be measured. Mismatch in the injection DAC introduces errors in the transfer function estimation and results in poor NSD at the ADC output. Techniques are described to improve the accuracy of the transfer function estimate despite DAC mismatch and despite the presence of an input signal.

A higher accuracy ADC circuit (e.g., in which the number of bits of the ADC circuit is twelve or greater) may need calibration multiple times during its working life to avoid bit weight errors. Described are techniques to address DAC element ratio errors between DAC element clusters in a DAC circuit in order to maintain the linear performance of analog-to-digital converter (ADC) circuits and digital-to-analog converter (DAC) circuits.

A charge rebalancing integration circuit can help keep an output node of a front-end integration circuit within a specified range, e.g., without requiring resetting of the integration capacitor. The process of monitoring and rebalancing the integration circuit can operate on a much shorter time base than the integration time period, which can allow for multiple charge balancing charge transfer events during the integration time period, and sampling of the integration capacitor once per integration time period, such as at the end of that integration time period. Information about the charge rebalancing can be used to adjust subsequent discrete-time signal processing, such as digitized values of the samples. Improved dynamic range and noise performance is possible. Computed tomography (CT) imaging and other use cases are described, including those with variable integration periods.

A novel and useful look-ahead time to digital converter (TDC) that is applied to an all digital phase locked loop (ADPLL) as the fractional phase error detector. The deterministic nature of the phase error during frequency/phase lock is exploited to achieve a reduction in power consumption of the TDC. The look-ahead TDC circuit is used to construct a cyclic DTC-TDC pair which functions to reduce fractional spurs of the output spectrum in near-integer channels by randomly rotating the cyclic DTC-TDC structure so that it starts from a different point every reference clock thereby averaging out the mismatch of the elements. Associated rotation and dithering methods are also presented. The ADPLL is achieved using the look-ahead TDC and/or cyclic DTC-TDC pair circuit.