The conventional testing methods based on specifications and using automatic test equipment are known to be time consuming and expensive. In addition, there are many problems with analog circuits such as the node accessibility problems and the lack of common test strategies and standards. Therefore, due to those difficulties, self-test techniques for analog and mixed signal blocks are gaining importance [5-6]. In fact, self–testing is the technique of designing additional hardware features into integrated circuits to enable them to perform self-testing and thereby reducing dependence on external automated test equipment (ATE). Thus, the self-testing approach is a Design-for-Testability (DFT) technique to provide simpler, faster, more efficient, and cost-effective testing of a chip [7].