Design for testability of mixed signal integrated circuits

A starting point for a set of design for testability (DFT) principles that can be used with mixed signal integrated circuits is presented. The authors argue that an effective DFT technique should enhance the ability to perform digital signal processing and other modern test techniques on analog macros embedded in the integrated circuit, since quality will be a driving force with increasing integration. The proposed test methodology consists of (1) establishing the digital test model for testing of digital logic and (2) establishing the analog test mode and each of the submodes (called test configurations) for serial or parallel testing of analog partitions. Digital and analog circuitry must be isolated from each other, i.e. an uncontrolled analog signal must not be able to affect the digital test mode and vice versa