Assured VLSI design with formal verification

Design and verification using formal logic extends existing VLSI design methods and tools. Such an extension provides rigorous support for design and verification at various levels of abstraction. Our design methodology combines design verification by mechanized theorem proving with conventional CAD tools. The theorem proving environment allows us to relate low level boolean implementations and high level arithmetic and instruction set specifications. We use the Higher-Order Logic theorem prover (HOL) to verify correctness relations between implementations and specifications. We use existing CAD tools to synthesize physical layouts and validate low level electrical and timing properties. Our CAD systems are Mentor Graphics GDT and MAGIC. To verify our design methodology, we fabricated a serial pipelined multiplier that is formally verified. Bit-serial circuits are widely used in signal processing. The multiplier chip was fabricated through MOSIS and worked correctly.