H03M1/1009

System and method for testing an analog-to-digital converter
11196437 · 2021-12-07 · ·

In accordance with an embodiment, a method for operating an analog-to-digital converter (ADC) includes: determining a trip point of a comparator of the ADC by applying a first signal having a first slope to an input of the ADC, and monitoring an output state of the comparator in response to the first signal; and after applying the first signal, applying a second signal having a second signal level based on the determined trip point of the comparator, monitoring values of an output code of the ADC in response to the second signal, and generating statistical information based on the monitored values of the output code, where the second signal is a static signal or has as second slope less than the first slope.

LOOP DELAY COMPENSATION IN A SIGMA-DELTA MODULATOR
20210376851 · 2021-12-02 ·

A circuit includes a transconductance stage having first and second outputs. The circuit also includes a comparator having first and second inputs. The first input is coupled to the first output, and the second input is coupled to the second output. The comparator includes first through fifth transistors and a pair of cross-coupled transistors. The pair of cross-coupled transistors is coupled to the second current terminals of the first and second transistors. The second current terminal of the third transistor is coupled to the second current terminal of the first transistor, and the first current terminals of the first, second, and third transistors are coupled together. The second current terminals of the fourth and fifth transistors are coupled together and to the control input of the third transistor.

DEVICES AND METHOD FOR CALIBRATING MEASURED VALUES

A device, which includes an input, configured to read in an analog signal, an analog/digital converter, configured to convert the analog signal into a digital value, and a processor, configured to determine a digital measured value. The processor is further configured to derive a calibrated digital value from the digital value with the aid of a linear calibration function and to derive the digital measured value from the calibrated digital value with the aid of a nonlinear measurement function. The processor modifies the linear calibration function in response to a calibration signal, based on an algorithm, which is based on the nonlinear measurement function, and a number of predefined comparison measured values.

Method and apparatus to correct ADC gain error induced from temperature drift

An analog to digital converter temperature compensation system comprising a comparator configured to compare an analog input signal to a compensated feedback signal and generate a comparator output. A SAR module processes the comparator output to generate a digital signal. A digital to analog converter, biased by a biasing signal having temperature change induced error, is configured to convert the digital signal to a feedback signal and a detector is configured to detect a signal that is proportional to temperature. A look-up table is configured to receive and convert the signal that is proportional to temperature to a compensation signal such that the compensation signal compensates for the temperature change induced error in the biasing signal. A summing node combines the feedback signal with the compensation signal to create a compensated feedback signal.

Transceiver and method and system for controlling an analog-to-digital converter in an observation path in the transceiver

A method and system for controlling an analog-to-digital converter (ADC) in an observation path in a transceiver. The transceiver includes a transmit path, a receive path, and an observation path. The observation path includes an analog buffer and an observation ADC. A controller generates a control signal to control sampling events at the observation ADC to activate the observation ADC at combined uniform and non-uniform sampling instants. The controller may also generate a second control signal indicating whether digital data obtained by the observation ADC is valid or not. The digital data generated by the observation ADC at non-uniform sampling instants is indicated as invalid and digital data generated by the observation ADC at uniform sampling instants is indicated as valid. The digital data indicated as invalid may be discarded and the digital data indicated as valid is used for calibration of the transmit path or the receive path.

Self-calibration function-equipped AD converter

An AD converter is provided with a control unit including a calibration control unit that controls an operation for calibrating the control unit and a conversion control unit that controls an operation for converting a target input voltage into a digital signal; a reference voltage unit that outputs a reference voltage; and an integrating converter unit including an integrating unit that generates an integrated voltage by integrating a predetermined unit voltage, a comparator that has two inputs and compares the integrated voltage and an input voltage or a reference voltage Vref, and a crossbar switch that switches connections between the case where the integrated voltage is inputted to one of the inputs of the comparator and the input voltage or the reference voltage Vref is inputted to the other input and the case where the input voltage or the reference voltage Vref is inputted to one of the inputs of the comparator and the integrated voltage is inputted to the other input.

ANALOG-TO-DIGITAL CONVERTER

An analog-to-digital converter (ADC) includes a coarse ADC that receives an analog input voltage, generates a first digital signal based on the analog input voltage using a successive approximation register (SAR) method, and outputs a residual voltage remaining after the first digital signal is generated. The ADC further includes an amplifier that receives the residual voltage and a test voltage, generates a residual current by amplifying the residual voltage by a predetermined gain, and generates a test current by amplifying the test voltage by the gain. The ADC further includes a fine ADC that receives the residual current and generates a second digital signal based on the residual current using the SAR method, and an auxiliary path that receives the test current and generates a gain correction signal based on the test current. The gain of the amplifier is adjusted based on the gain correction signal.

RAMP VOLTAGE GENERATOR AND IMAGE SENSOR
20220173745 · 2022-06-02 ·

A ramp voltage generator includes: a ramping cell array including a plurality of ramping current cells; a calibration cell array including a plurality of calibration current cells; and a current-voltage converter suitable for converting a current supplied from activated ramping current cells among the ramping current cells and activated calibration current cells among the calibration current cells into a voltage to generate a ramp voltage.

Analog-to-digital converter

An analog-to-digital converter (ADC) circuit includes a signal input terminal, a sample-and-hold circuit, and a successive approximation register (SAR) ADC. The sample-and-hold circuit includes an input terminal coupled to the signal input terminal. The SAR ADC includes a comparator, a first capacitive digital-to-analog converter (CDAC), and a second CDAC. The first CDAC includes a first input terminal coupled to the signal input terminal, a second input terminal coupled to an output terminal of the sample-and-hold circuit, and an output terminal coupled to a first input terminal of the comparator. The second CDAC includes a first input terminal coupled to the signal input terminal, an output terminal coupled to a second input terminal of the comparator.

PROXIMITY SENSING DEVICE
20220163386 · 2022-05-26 ·

The present invention provides a proximity sensing device, which comprises an ambient light calibration digital-to-analog converter and at least one crosstalk calibration digital-to-analog converters. The proximity sensing device is able to quickly generate calibration parameters for the interference caused by the ambient list and crosstalk caused by different reflection, to calibrate the sensed signals to avoid wrong judgments.