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1	Stuck-At Logic Fault Models Boolean Logic Equations What can be wrong, logically? Testing, correct design, defective copy Physical Defects, Logic Fault Models The AND Logic Gate Simple Example Implementation of Exclusive-OR Full Adder
2	Boolean Logic Equations Logic Values, 1 or 0 Operations: l, +, ¬, Å, ¬l, ¬+, 0, 1, ¤,… Combinational Logic Þ f (inputs) Operations f (a, b, c, d) = (a + b) l (c + d) f(0,b,c,d) = bc + bd f(a,b,1,d) = a + b A variable can be a constant 1 or 0, i.e. Stuck-At-1 or Stuck-At-0 respectively.
3	What Can be Wrong, Logically A variable can have the wrong logic value, either a 0 or a 1. The function can change. State or memory can be introduced. Let us concentrate on combination logic, single failures. Stuck-At Faults: s@0 and s@1
4	Testing Correct Design, design verification Manufacture, implementation Defective Copies Test the parts Boolean tests Evaluate the tests, i.e. detect all Stuck-At faults.
5	Physical Defects, Logic Fault Models Physical Failure Mechanism, cause, e.g. contamination or speck of dirt Physical Failure Mode, resulting defect, e.g. extra metal connecting independent wires Electrical Fault Model, electrical behavior of defective circuit, e. g. resistive connection between two wires Logical Fault Model, logical behavior of defective circuit, e. g. signal value always logic 0.
6	The AND Logic Gate f = a l b Stuck-At Faults A-s@0, A-s@1 B-s@0, B-s@1 OUT-s@0, OUT-s@1 Fault List Equivalent Faults A-s@0 º B-s@0 º OUT-s@0
7	Simple Example AorBC
8	AorBC for faults
9	F = Al(B+C) with Fault List
10	F = Al(B+C) with Collapsed Fault List
11	F = Al(B+C) with Fault Dictionary
12	F = Al(B+C) with Fault Coverage
13	Implementation of Exclusive-OR
14	Full Adder
15	Full Adder with internal nodes
16	Full Adder labeled
17	Full Adder Fanout Example
18	Full Adder Reconvergent Fanout Example
19	Full Adder Fault List
20	Full Adder Equivalent Fault List