Interviewed by Douglas Fairbairn and Uday Kapoor on 2021-01-26 in Saratoga, CA X9400.2021
© Computer History Museum
Les Kohn is very well-known in the Silicon Valley as an architect’s architect and a prolific and successful entrepreneur. He was born in Oakland CA in 1956 and grew up in nearby San Mateo. He was the son of an engineer and developed an interest in computers at an early age. He wrote his first FORTRAN program in the seventh grade. He attended Caltech, in Pasadena CA, where he majored in physics, but with a strong bent towards computer science.
Upon graduation with a BS degree, he decided leave academia and found a position working at National Semiconductor working on the architecture of their next generation processor. One of the major lessons from this assignment was to understand the limitations of using complex, micro-coded instructions. He became an early believer in RISC processors and their inherent advantages as the rest of the computer architecture became more complex.
After a series of other responsibilities at National, Les moved onto Intel. There he played a major role in the development of the Intel 386 microprocessor, which became a phenomenal success. He then moved onto the Intel 860 which was targeted at high end computing and graphics.
After the 860 microprocessor project wrapped up, he and friends decided to test their skills in the startup world with a company called Aquest. Their goal was to develop an 860-based workstation. When that company foundered, he moved onto Sun Microsystems where he played a lead role in the development of Sun’s next generation SPARC processor.
Following Sun, he wanted to develop his interest in a more application-specific focus. He joined C-Cube to work on video compression and related technologies. He was there for 6 years. While there, he led the development of the first single-chip MPEG2 solution.
Following the time at C-Cube, he joined Kunle Olukuton, a professor from Stanford, at a company called Afara where they developed a multi-threaded processor with fairly simple pipelines. This architecture became the model for modern Graphics Processors (GPUs). He then found himself back at Sun, when Afara was acquired.
After a year at Sun, Les decided he was happier in a smaller company environment. He became an entrepreneur in residence at Benchmark, where he formulated a plan for his next company, Ambarella. The goal for Ambarella was to implement the next important video compression technology, H.264, in a chip. This technology enabled the replacement of tape-based video cameras with solid state storage. As of 2021, Les has been with Ambarella for 17 years as they have continued to advance the state of the art in video and image processing, including the latest machine learning technologies.
* Note: Transcripts represent what was said in the interview. However, to enhance meaning or add clarification, interviewees have the opportunity to modify this text afterward. This may result in discrepancies between the transcript and the video. Please refer to the transcript for further information – http://www.computerhistory.org/collections/catalog/102792135
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Catalog Number: 102792136
Lot Number: X9400.2021