Statistical Method of Measuring the Differential Linearity of an Analog/Digital Converter Using a Pseudo-Random Triangle Wave Stimulus

摘要

The differential linearity of an analog/digital converter is measured by a test method that eliminates the need for precision calibrated test equipment. A triangle waveform with a pseudo random period is applied to the analog/digital converter input. The waveform has a uniform amplitude probability density function. Therefore, any analog/digital converter input voltage has an equal chance of being sampled by the analog/digital converter. The number of times each possible analog/digital converter output code word occurs is counted by a microprocessor. These numbers are a direct measure of differential linearity with an accuracy described by the theory of repeated random sampling. (Author)