Report Number: CSL-TR-93-591
Institution: Stanford University, Computer Systems Laboratory
Title: Logic Synthesis for Concurrent Error Detection
Author: Touba, Nur A.
Author: McCluskey, Edward J.
Date: November 1993
Abstract: The structure of a circuit determines how the effects of a
fault can propagate and hence affects the cost of concurrent
error detection. By considering circuit structure during
logic optimization, the overall cost of a concurrently
checked circuit can be minimized. This report presents a new
technique called structure-constrained logic optimization
(SCLO) that optimizes a circuit under the constraint that
faults in the resulting circuit can produce only a prescribed
set of errors. Using SCLO, circuits can be optimized for
various concurrent error detection schemes allowing the
overall cost for each scheme to be compared. A technique for
quickly estimating the size of a circuit under different
structural constraints is described. This technique enables
rapid exploration of the design space for concurrently
checked circuits. A new method for the automated synthesis of
self-checking circuit implementations for arbitrary
combinational circuits is also presented. It consists of an
algorithm that determines the best parity-check code for
encoding the output of a given circuit, and then uses SCLO to
produce the functional circuit which is augmented with a
checker to form a self-checking circuit. This synthesis
method provides fully automated design, explores a larger
design space than other methods, and uses simple checkers. It
has been implemented by making modifications to SIS (an
updated version of MIS [Brayton 87a]), and results for
several MCNC combinational benchmark circuits are given. In
most cases, a substantial reduction in overhead compared to a
duplicate-and-compare implementation is achieved.
http://i.stanford.edu/pub/cstr/reports/csl/tr/93/591/CSL-TR-93-591.pdf