A gain calibration device for an ADC residue amplifier includes a DAC and a flash ADC. The DAC is configured to convert the digital signal to an analog signal, and the DAC includes a calibration module used in the gain calibration of the ADC residual amplifier. The flash ADC is configured to generate a digital signal, the flash ADC includes a plurality of comparators, the total number of the plurality of comparators is equal to the number of output bits of the flash ADC, and the comparators are configured to be unevenly distributed in an input range.

A switched-capacitor amplifier comprises a comparator, sample and amplification capacitors and a controller to control charge and discharge current sources in dependence on an output signal of the comparator. A closed loop control circuit is configured to determine the delay of the comparator and control an offset of the comparator in response to the determined delay.

A high-speed and high-precision photonic analog-to-digital conversion device capable of realizing intelligent signal processing. Learning ability of deep learning technology is utilized to learn the nonlinear response and channel mismatch effect of the system and configure optimal parameters of the deep network. Deterioration of photonic analog-to-digital conversion system performance caused by nonlinear distortion and channel mismatch distortion is eliminated in real time, and performance indicators thereof are improved. By using the induction and deduction ability of deep learning technology, intelligent signal processing of the input signal is realized, and users are provided with digital signals that meet the requirements. It's important for improving the performance of microwave photonic systems that require high sampling rate, high time precision, and high sampling accuracy, such as microwave photonic radar and optical communication systems, and also critical to improve the signal processing ability of such systems under complex conditions.

Disclosed is a high-speed and low-power pipelined analog-digital converter (ADC) using a dynamic reference voltage and a 2-stage S/H. The pipelined ADC includes a 2-stage sample-and-hold (S/H) configured to secure a conversion time corresponding to a clock cycle per stage and to apply only a buffer to an input signal path, a reference voltage generator configured to receive the output of the D flip-flop of a previous stage as an input signal and to generate a required reference voltage during a half cycle of a sample frequency, and a comparator configured to include a linear transconductor (LT), a rail-to-rail latch (R2R) and a D flip-flop and to generate the output of the ADC and input to the reference voltage generator of a next stage for generating a reference voltage using the output of the D flip-flop.

The analog-to-digital converter includes a first stage in which a voltage to be converted is applied to the input of a first comparator. The first comparator delivers, on a first digital output, a first digital result representative of the comparison between the voltage to be converted and the comparison voltage. The first digital output is connected to a calculator of a first intermediate voltage. A second comparator compares the first intermediate voltage with the comparison voltage and delivers a second digital result on a second digital output terminal. The second digital output terminal is connected to a second calculator of residual voltage that is a function of the voltage to be converted, of first and second voltages and of the first and second digital results. The first calculator is formed by the second calculator.

The analog-to-digital converter includes a first stage in which a voltage to be converted is applied to the input of a first comparator. The first comparator delivers, on a first digital output, a first digital result representative of the comparison between the voltage to be converted and the comparison voltage. The first digital output is connected to a calculator of a first intermediate voltage. A second comparator compares the first intermediate voltage with the comparison voltage and delivers a second digital result on a second digital output terminal. The second digital output terminal is connected to a second calculator of residual voltage that is a function of the voltage to be converted, of first and second voltages and of the first and second digital results. The first calculator is formed by the second calculator.

Disclosed is a high-speed and low-power pipelined analog-digital converter (ADC) using a dynamic reference voltage and a 2-stage S/H. The pipelined ADC includes a 2-stage sample-and-hold (S/H) configured to secure a conversion time corresponding to a clock cycle per stage and to apply only a buffer to an input signal path, a reference voltage generator configured to receive the output of the D flip-flop of a previous stage as an input signal and to generate a required reference voltage during a half cycle of a sample frequency, and a comparator configured to include a linear transconductor (LT), a rail-to-rail latch (R2R) and a D flip-flop and to generate the output of the ADC and input to the reference voltage generator of a next stage for generating a reference voltage using the output of the D flip-flop.

An analog-to-digital converter includes a first circuit and a second circuit. The first circuit includes a first quantizer that digitizes an input first analog voltage, has a function of subtracting an analog voltage generated based on the digitalized first value from the first analog voltage, has a function of amplifying a first analog residual voltage which is a result of the subtraction, and a first output drive amplifier that outputs the amplified first analog residual voltage. The second circuit includes a second quantizer that digitizes an input second analog voltage, has a function of subtracting an analog voltage generated based on the digitalized second value from the second analog voltage, has a function of amplifying a second analog-residual voltage which is a result of the subtraction, and a second output drive amplifier that outputs the amplified second analog residual voltage.

A system includes an analog-to-digital converter (ADC) including an ADC input terminal; an ADC output terminal; and analog components configured to convert an analog signal received at the ADC input terminal to a digital signal. The system also includes a histogram estimation circuit coupled to the ADC output terminal and configured to generate information on a plurality of codes generated by the ADC and determine a region defining a range of codes corresponding to an occurrence of an error caused by the analog components of the ADC. The system also includes a dither circuit coupled to the ADC input terminal and configured to introduce a dither in the analog signal to generate a modified analog signal.

A readout circuit includes a first analog circuit configured to receive an output of a first sub-array of a pixel array and to output a first signal based on the received output of the first sub-array. A second analog circuit is configured to receive an output of a second sub-array of the pixel array and to output a second signal based on the received output of the second sub-array. A first digital circuit is configured to receive the first signal and convert the first signal to a first digital signal, and receive the second signal and convert the second signal to a second digital signal.