Soon after, he switched majors and was part of Professor Brayton’s group. Right after inducting Vigyan in his group, Professor Brayton got him an internship working at Motorola in Austin, Texas. His supervisor was Carl Pixley, now of Synopsys, who asked him to do research on formal verification techniques, which later would evolve into his thesis topic. Carl also asked him to verify the cache controller in a PowerPC chip, where Vigyan found his first post-silicon bug using formal verification.
When his doctoral studies were wrapping up, he was assigned a dream-team thesis committee if there ever was one. Along with Professor Brayton, he presented to Dr. Alberto Sangiovanni-Vincentelli and the late Dr. Richard Newton. A funny thing happened during his qualifying examination presentation for his thesis topic. Professor Newton stopped him and said that the formal verification methodology he was outlining wouldn’t work. Professor Sangiovanni-Vincentelli jumped in, arguing Vigyan’s points. Vigyan and Professor Brayton went back to Brayton office to talk it through. He went on to get his Ph.D., with a thesis in the methodology he proposed.
With the newly minted degree, Vigyan joined Cadence Berkeley Labs and began developing what would become Cadence’s formal verification entry HECK, an equivalence checking tool. Vigyan stayed around for about 18 months after his project was commercialized, then partnered with another Cadence engineer, Joe Higgins, originally from the analog/mixed-signal group, to launch a verification company. They called their fledgling startup Tempus Fugit, Latin for “time flies.” Vigyan and Joe looked at areas within the formal verification discipline, bootstrapping themselves with consulting services projects. Their customers’ designs became their inspiration.
“I was inspired by the designs I saw at Apple,” says Vigyan. He and Joe began developing model checking software to verify the correctness of standard interfaces, such as PCI, USB or FireWire. Even though there were nine other commercial tools in formal verification market from 0-In, Averant, Axiom, Cadence, Chrysalis, Real Intent, Synopsys, Verplex and Verysys at that time, Vigyan and Joe believed they could build a differentiated company. Within three months from the start of product development, they had their verification engines and attracted early customers Ikanos and NVIDIA.
Vigyan persuaded both with the convincing offer: “Let me use my tool on your design and pay me if I find bugs.” He succeeded at both companies by finding important bugs.