System for the testing of high-resolution ADCs at frequency of 1 MHz

A system for the testing of ADCs at the frequency range of 1 MHz was designed and prototyped at the Dept. of Measurement, CTU FEE. Two methods were applied to suppress the influence of signal distortion: 1) filtering by special high-quality filters with a near-linear transfer characteristic; 2) filtering by low-cost filters and the application of following numerical correction of residual distortion. Low-cost as well as high-quality filters were manufactured. Experimental results showed that the method is directly applicable for the testing of ADCs with the ENOB up to 14 in case of low-cost filters and up to 20 in case of high-quality filters. An extension of the method for the testing of ADCs with hither ENOB can bring an application of the frequency spectrum correction method