Abstract: This disclosure describes a method for accomplishing sequential logical equivalence verification using a hierarchical piecewise approach. Initially, the method provides a reference semiconductor design and a second semiconductor design with logic edits relative to it. The method submits both to formal verification to check the reference design against the second semiconductor design with all edits disabled 200. The semiconductor design is partitioned 202 and associated input constraints 204. The edits are further grouped 206 and ordered 208. The invention also discovers a set of dependencies of the logic edits 210 and checks that the ordering of groups obeys the dependencies 212. Each group of edits is further submitted to formal verification 214 and any input constraints assumed for any partitions are verified in their enclosing partition 216. Finally, the method reports success if formal verification succeeds on each group of logic edits and on each set of input constraints 218.

Abstract: This disclosure describes a method for accomplishing sequential logical equivalence verification using a hierarchical piecewise approach. Initially, the method provides a reference semiconductor design and a second semiconductor design with logic edits relative to it. The method submits both to formal verification to check the reference design against the second semiconductor design with all edits disabled 200. The semiconductor design is partitioned 202 and associated input constraints 204. The edits are further grouped 206 and ordered 208. The invention also discovers a set of dependencies of the logic edits 210 and checks that the ordering of groups obeys the dependencies 212. Each group of edits is further submitted to formal verification 214 and any input constraints assumed for any partitions are verified in their enclosing partition 216. Finally, the method reports success if formal verification succeeds on each group of logic edits and on each set of input constraints 218.

Abstract: A method and apparatus for creating a memory model for use in modeling a physical memory of an electronic circuit design. Memory write operations to the physical memory and memory read operations are modeled in a lookup table. The number of entries in the lookup table is limited by an upper bound representing a total number of memory operations that can occur over a given number of clock cycles.

Abstract: A method and apparatus for creating a memory model for use in modeling a physical memory of an electronic circuit design. Memory write operations to the physical memory and memory read operations are modeled in a lookup table. The number of entries in the lookup table is limited by an upper bound representing a total number of memory operations that can occur over a given number of clock cycles.

Abstract: A video tracking system and a program employing frequency-domain analysis for extracting RHEED intensity oscillation data for film growth on rotating substrates. In initial experiments on GaAs growth, excellent (2%) agreement has been obtained between oscillation frequencies measured for static substrates and substrates with rotation rates as high as 10 rpm. The capability of performing RHEED analysis on rotating substrates could lead to improvements in the quality of complex epitaxial structures and interfaces for which interrupting rotation can have a deleterious effect.