FAULT MACROMODELING AND A TESTING STRATEGY FOR OPAMPS

In this paper, we propose a simple testing technique based on DC measu rements for operational amplifiers. We first develop a comprehensive m acromodel for the transistor-level opamp to alleviate the efforts of f ault simulation. By incorporating appropriate I/O characteristics into the macromodel, the output deviation due to the modeling error can be significantly reduced. We use the transistor short/bridging faults to illustrate the efficiency of our proposed technique. Experimental res ults show that a high fault coverage can be achieved for the stand-alo ne opamp by measuring two DC parameters V(o_max) and V*(o_min). For t he embedded opamps, many short/bridging faults cannot be detected by t raditional functional testing. However, by using similar DC measuremen ts along with a design for testability (DFT) scheme, we can improve th e fault coverage dramatically.