Improving the dynamic measurements of ADCs using the 2-ADC method

Testing high-resolution analog-to-digital converters (greater than or equal to 12 bit) at high input frequencies (>5 MHz) becomes more difficult, because the disturbances of the automatic test equipment (ATE) become more significant. Although a lot of improvements have been made to modern ATEs during recent years, they are not sufficient, given the components specifications, especially the signal-to-noise ratio (SNR) parameter. This paper briefly describes the errors of the converters, which have to be tested, and those introduced by the equipment. From this description, a model has been built to simulate a new method based on the simultaneous measurement of two converters and which is intended to give an accurate estimation of the SNR, removing the correlated disturbances. The simulation results show the potential benefits of the method, and eventually, the experimental results in an industrial environment are given and discussed. (C) 2000 Elsevier Science B.V. All rights reserved.