Development of redesign process for digital VLSI system

Re-engineering of electronic circuits has received considerable interest in the design automation community. Re-engineering is the examination and alternation of a system to reconstitute it in a new form, which potentially involves changes at the requirements, design, and implementation level. This paper deals with "redesign" problem in which the original implementation information is either missing or incomplete. Given a target circuit with a test set and blocks of missing gates, a circuit is redesignable if the transfer function of each block of missing gates can be derived from the partial knowledge in existing implementation. The derived transfer functions are then used to construct the missing blocks. This paper presents a redesign process for digital circuits and systems.