An arithmetic approach to the analysis of multiple faults verification and synthesis at switch-level

Switch-level modeling and simulation has become an important method of predicting the behaviour of CMOS circuits under the presence of faults. Many important phenomena in CMOS circuits, such as bi-directional signal propagation, charge sharing and variations in driving strength can be reliably modeled using this technique. This paper presents an algorithm for modeling directional and bi-directional CMOS circuits with an arithmetic solution for circuit verification and fault synthesis. This new approach is capable of simulating multiple fault injection into the circuit and speeds up switch-level simulation. Other advantages of this algorithm are its application in the mapping of single and multiple faults from switch level to gate level and the ability to function as a multi-level model. Multiple faults can be of the same or different types. Experimental results using Cadence tools show that the algorithm is successful and reliable for CMOS technology.