Mechanisms for reducing or eliminating a quantization error caused by a quantizer of a continuous-time (CT) residue generation system are disclosed. In particular, systems and methods described herein are based on using a dither generation and injection circuit that can perform a high-pass filtering of the additive dither signal (i.e., a high-pass shaped dither signal). Using high-pass shaped dither signals is expected to improve quantizer linearity without significantly reducing the available error correction range. The applied dither may be particularly effective at minimizing signal-dependent distortion in ADC output spectrum caused by the quantizer when the quantization error cancellation accuracy may be insufficient.

Methods and devices for digitizing an analog repetitive signal using waveform averaging are described. An example method includes generating a discrete set of analog dither offset voltages, wherein at least two of the discrete set of analog dither offset voltages are different from each other, receiving the analog repetitive signal comprising multiple instances of a waveform, wherein the waveform has a waveform duration, generate a timing alignment to align each waveform of the analog repetitive signal and the corresponding analog dither offset voltage over the waveform duration, combining, based on the timing alignment, each waveform and the corresponding analog dither offset voltage over the waveform duration to produce an analog output signal, converting the analog output signal to a digital output signal, and producing, based on the timing alignment, a digital averaged signal based on averaging the multiple instances of the waveform in the analog output signal.

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.

Calibration of continuous-time (CT) residue generation systems can account and compensate for mismatches in magnitude and phase that may be caused by fabrication processes, temperature, and voltage variations. In particular, calibration may be performed by providing one or more known test signals as an input to a CT residue generation system, analyzing the output of the system corresponding to the known input, and then adjusting one or more parameters of a forward and/or a feedforward path of the system so that the difference in transfer functions of these paths may be reduced/minimized. Calibrating CT residue generation systems using test signals may help decrease the magnitude of the residue signals generated by such systems, and, consequently, advantageously increase an error correction range of such systems or of further stages that may use the residue signals as input.

A device for true random number generation is disclosed. The device comprises an antenna and an analog processing unit for analog processing of a signal received from the antenna. An analog to digital (AD) converter is used for converting an analog signal generated by the analog processing unit into a digital signal. An isolation means is applied for temporarily isolating the antenna from the analog processing unit and the AD converter to generate a noise signal. A sampling means is used for sampling output values generated by the AD converter when the antenna is isolated from the analog processing unit and the AD converter. A digital processing unit is used for processing the sampled output values generated by the AD converter. The digital processing unit is configured to generate a random number based on one or more of the output values generated by the AD converter.

A digital signal generation assumes that a base frequency (the frequency with which the primitive phase angles are specified relative to) is equal to the carrier frequency for all relevant times. But this causes errors in the digital signals output to each array element transducer. Thus, it is necessary for the development of a signal generation system that is capable of producing a digital signal using the free selection of amplitude and phase. This is used to produce a substantially error-free signal that preserves the amplitude and phase relative to a constant base frequency while allowing the carrier frequency to vary.

A dither capacitor, separate from the capacitor sampling the input signal, can be used to inject the additive dither in the switched-capacitor network of the track and hold circuit. This implementation can be referred to as a split-capacitor dither injection. The dither capacitor can be connected to a summing node of the switched-capacitor network. Using a separate capacitor allows the dither to be isolated from the capacitor that is sampling the input signal and avoids kick-back errors.

A digital signal generation assumes that a base frequency (the frequency with which the primitive phase angles are specified relative to) is equal to the carrier frequency for all relevant times. But this causes errors in the digital signals output to each array element transducer. Thus, it is necessary for the development of a signal generation system that is capable of producing a digital signal using the free selection of amplitude and phase. This is used to produce a substantially error-free signal that preserves the amplitude and phase relative to a constant base frequency while allowing the carrier frequency to vary.

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.

An analog-to-digital converter circuit module utilizing dither to reduce multiplicative noise. A dither generation circuit generates a noise-shaped analog dither signal having lower amplitudes at frequencies below a cutoff frequency than at frequencies above the cutoff frequency. The noise-shaped analog dither signal is added to the input analog signal to be converted and the summed signal applied to an analog-to-digital converter The dither generation circuit may be implemented as an analog dither generator followed by an analog high-pass filter. The dither generation circuit may alternatively be implemented digitally, for example with a digital noise-shaping filter applying a high-pass digital filter to a pseudo-random binary sequence. The digital dither generation circuit may alternatively be implemented by one or more 1-bit sigma-delta modulators, each generating a bit of a digital dither sequence that is converted to analog.