Testing of Adcs by Frequency-domain Analysis in Multi-tone Mode

In this paper the testing of analog-to-digital converters (ADCs) by frequency-domain analysis in multi-tone mode is investigated. The theoretical expressions of some of the most important ADC dynamic parameters are derived. Also, the theoretical expression of the difference between the ADC effective number of bits (ENOB) obtained by testing in multi-tone mode and the ENOB obtained by testing in the single-tone mode is derived. From the theoretical expression of this difference some important conclusions concerning the accuracy in the evaluation of ENOB by testing in multi-tone mode are drawn. Some experimental results are presented in order to validate these conclusions. The experiments were carried out using the test system MULTI-TONE ADC TEST, specially developed for this purpose.