Using Checking Circuit Results to Switch Logically Redundant Inputs
Original Publication Date: 1985-Feb-01
Included in the Prior Art Database: 2005-Feb-18
For very large VLSI (very large-scale integration) chips there is a need for decoder circuits to choose among available logically redundant inputs. The reason for redundancy is that some units may have manufacturing defects, and other units may fail temporarily (because of alpha particles or other intermittent events) or permanently (because of metal migration, burnout, or other problems). With redundant units, chips can be made with higher manufacturing yields and greater field reliability. Many chips have circuits whose only function is to detect errors. The signals generated by these error detection circuits can be used to make sure that erroneous results are not propagated beyond the malfunctioning unit.