An Analogue and Mixed-signal Fault Simulation Tool Based on Tcl/tk and Hspice

This paper will describe a fault simulation tool for analogue and mixed-signal circuits based on the HSpice circuit simulator and a graphical user interface (GUI)/Integration tool created using Tcl/Tk. The structure and use of the tool is demonstrated with example to the fault-free and fault simulation of a weighted-current Digital to Analogue Converter (DAC). Fault simulation techniques utilise a simulation model for a Circuit Under Test (CUT) and models for potential faults that may be considered to exist in a fabricated circuit. The paper will discuss the area of analogue and mixed-signal fault simulation and how the tool introduced here may have a number of advantages for the user. The tool was written to be straightforward to set-up and use, provide the end-user with flexibility in terms of enhancing the core functionality and be capable of operating on both UNIX and PC Windows platforms.