DFT for analog and mixed signal IC based on IDDQ scanning

The cost of integrated circuits increases with the complexity and integration density. This has led designers to consider testing from the design phase; that´s what we call DFT (design for testability). In this paper, we propose a DFT solution, based on technique of I_DDQ measuring current, by incorporating a Built-In Current sensor, whose function is to detect power consumption of different circuits under test, and by applying an intelligent switching technique, between BICS and the circuits under test. This DFT technique is intended for digital, analog and mixed integrated circuits. The final system represented, by the name of the TEST AND CONTROL UNIT, consists on a test vector generator, an interconnection logic block, a BICS and a diagnostic unit, designed to test all circuits of the wafer by using a single BICS. The aim of system is to reduce the time required for functionality test of each circuit in the mass production. It offers a practical test solution for integrated circuits designers.