A circuit includes a nonlinear analog-to-digital converter (ADC) configured to provide a first digital output based on an analog input signal. The circuit also includes a linearization circuit having a lookup table (LUT) memory configured to store initial calibration data. The linearization circuit is coupled to the nonlinear ADC and is configured to: determine updated calibration data based on the initial calibration data; replace the initial calibration data in the LUT memory with the updated calibration data; and provide a second digital output at a linearization circuit output of the linearization circuit based on the first digital output and the updated calibration data.

The present disclosure provides systems and methods for identifying failures in an analog to digital (A/D) converter. An intelligent electronic device (IED) may monitor a digital output of one or more A/D converters. The IED may determine a slope value limit associated with the A/D converter. The IED may determine an output slope value of the digital output based on a difference of a converter output value measured at a first time and a converter output value measured at a later time. If the determined output slope value exceeds the slope value limit, the IED may identify a failure of the A/D converter. An IED may determine that concurrent failures in multiple, parallel A/D converters are indicative of a problem upstream from the A/D converters.

A method of determining Integral Non-Linearity (INL) of an Analog-to-Digital Converter (ADC) is provided. The method includes providing an input signal to the ADC, phase-locking a clock signal of a clock of the ADC to the input signal, generating a plurality of samples at a sampled phase on the input signal for a plurality of sampled phases, applying averaging to the plurality of samples for each sampled phase to generate a reconstructed ADC output signal, and determining the INL of the ADC based on a comparison of the reconstructed ADC output signal to a theoretical ADC output signal.

The present invention discloses a method of testing an analog-to-digital converter (ADC). The method includes receiving a series of analog signals from a tester site, converting the series of analog signals to a series of digital code words using an ADC, evaluating the ADC based on the series of digital code words using an ADC test setup and generating an output signal identifying whether the ADC has passed the testing.

A method for use in testing an analog-to-digital converter. The method includes providing a set of bins, varying a voltage, taking samples of the voltage, providing a selection flag, associating each sample with one bin of the set of bins, and observing a number of samples associated with the bins. An apparatus includes an analog-to-digital converter configured to convert a voltage at an input node to a digital representation provided at an output node. The input node is configured to be coupled to a voltage generator. A sample select unit is configured to determine if a voltage at the input node at least equals a first threshold level and does not exceed a second threshold level. The apparatus is configured, based on the determining, to selectively associate the digital representation with a bin of a set of bins.

This invention discloses a method and a circuit for testing a successive approximation ADC. The test method includes the following steps: receiving a plurality of digital output codes of a SAR ADC; counting the number of odd numbers and the number of even numbers of the digital output codes; and determining whether an error occurs in the SAR ADC based on the number of odd numbers and the number of even numbers.

Provided is an analog-to-digital converting device. The analog-to-digital converting device may include a determination circuit that determination whether a reference digital signal or a determination digital signal obtained by conversion of a reference voltage or a determination voltage matches a test pattern for the reference voltage, and it is possible to monitor whether the analog-to-digital converting device normally operates, according to whether there is matching.

This invention discloses a method and a circuit for testing a successive approximation ADC. The test method includes the following steps: receiving a plurality of digital output codes of a SAR ADC; counting the number of odd numbers and the number of even numbers of the digital output codes; and determining whether an error occurs in the SAR ADC based on the number of odd numbers and the number of even numbers.

A method for use in testing an analog-to-digital converter. The method includes providing a set of bins, varying a voltage, taking samples of the voltage, providing a selection flag, associating each sample with one bin of the set of bins, and observing a number of samples associated with the bins. An apparatus includes an analog-to-digital converter configured to convert a voltage at an input node to a digital representation provided at an output node. The input node is configured to be coupled to a voltage generator. A sample select unit is configured to determine if a voltage at the input node at least equals a first threshold level and does not exceed a second threshold level. The apparatus is configured, based on the determining, to selectively associate the digital representation with a bin of a set of bins.

An analog-to-digital converter (ADC) system for providing a calibrated voltage measurement without an external reference voltage may include an ADC circuit, including an analog ADC input and a digital ADC output. The ADC system may also include circuitry to generate a first internal reference voltage and a second internal reference voltage. The ADC system may also include circuitry configured to provide a selected output from a number of inputs, wherein the inputs include inputs to receive (1) the first internal reference voltage, (2) the second internal reference voltage, and (3) a user-provided analog signal of interest, wherein the selected output can be connected to the analog ADC input, an external voltage measurement device, or both.