Simic is a functional/gate/switch level simulator with capabilities far beyond other simulation products from commercial vendors or academia. Simic has a very long history, and pioneered many simulation concepts found in many commercial simulation engines today, but it still has many features not found in any other simulator.

Simic's long history begins in the mid 70's. At that time a team of Engineers composed from RCA Laboratories and the RCA Advanced Technology center were brought together at the RCA Solid State Technology Center in Somerville, NJ. This team had already built several fault-free and fault simulators in use at RCA since the early 60's The goal of the team was to develop a Simulator that would be accurate, would provide the highest ability to find design problems, and would allow the designed to correct them in the minimum time. The Mimic Logic Simulator was released in 1978 and soon totally replaced breadboarding as the method for designing ICs throughout RCA. Mimic's reputation spread internationally and soon RCA began offering IC design services via its new ASIC design division. They sold their design and fabrication service with the slogan, "If Mimic says it works, RCA will guarantee it works". The division had an over 99% success rate. Over sixty companies in locations all over the globe used Simic for IC design. When GE bought RCA and then sold the division to Harris in the late 80's, the division was still growing while the rest of the industry was shrinking. Harris ended up closing the division's doors in 1989 (which is another story). Genashor Corp was created from the developers of Mimic and many other CAE tools within RCA. Starting from a blank sheet of paper, the next generation simulator, Simic, was born. The engine is thirty times faster than Mimic's, and outperforms Mimic in both functionality and accuracy. Simic has been used by several companies, universities, and individuals around the world, both as a supurb design teaching tool and to create real designs with an incredible first working silicon success record.

Working with the University of Manchester in England, Simic was proven to be the only logic simulator that could accurately model asynchronous design elements and discover critical hazards in designs using these models. This culminated in a paper in Async 94.


For years the logic simulation industry had been focusing on performance, to the exclusion of all else. Simic boasts high performance, without cutting corners in accuracy and functionality. For example, no other commercial gate simulator properly models wiretied drivers. Without this, it is impossible to trust the timing at bus structures. The bus-hold circuit, popular in today's circuit architectures, can actually result in a steady-state error at the bus that is left undetected by other simulators!

In addition to accuracy, Simic boasts a suite of built-in hazard analysis that can detect many potential problems (such as essential hazards) that are completely ignored by other simulators. When this analysis is combined with Simic's sophisticated interactive debugging capabilities, users can quickly pinpoint problematic areas.

Besides circuit verification, Simic has fault analysis and grading capabilities that can automatically and properly classify faults such as clock and reset faults as Detected or Undetected. No more hours or days of trying to generate tests for faults that were incorrectly marked as potential detections

Simic includes a built-in tester emulation mode. This allows test engineers to debug their test programs in the simulator, rather than taking expensive testing time away from manufacturing. The emulator can be used with the fault analysis to give an accurate picture of fault coverage, based on the actual test program.

In addition to all these features, Simic is very efficient in memory utilization. It typically uses 50x less memory than comparable simulators with better simulation throughput. One client who was forced to use a large server to run one simulation at a time found that Simic could run on the smaller workstations on each engineer's desk. Design productivity went up more than 10 fold when Simic was used.

To find out more about Simic, view the Simic Engineering Guide For IC Design Verification and our paper from Async94 Tools for Validating Asynchronous Digital Circuits. They contain more details on some of the unique capabilities found only in Simic.

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Last modified: June 28, 2007