Walden C. “Wally” Rhines is an American engineer and businessman. Rhines is President and CEO of Mentor Graphics, a Siemens Business and previously worked as an executive at Texas Instruments. Rhines was named overall CEO of the Year by Portland Business Journal in 2012 and Oregon Technology Executive of the Year by the Technology Association of Oregon in 2003. He was named an IEEE Fellow in 2017.
While at Stanford, Rhines co-invented the magnesium-doped gallium nitride blue light-emitting diode, for which he, Herb Maruska and David Stevenson were awarded a U.S. patent in 1974. Isamu Akasaki built directly on this gallium-nitride research and eventually won the 2014 Nobel Prize in Physics, along with Hiroshi Amano and Shuji Nakamura. Rhines worked at Texas Instruments from 1972 to 1993, serving as executive vice president of the semiconductor group and president of the data systems group. While at TI, Rhines supervised development of speech synthesis chips used in the Speak & Spell; developed the first publicly available computer program to calculate the Black-Scholes value of a stock option; and supervised the creation of the TMS320digital signal processor. In a 1985 profile of Rhines in the Austin American-Statesman, industry consultant Will Strauss told reporter Russell Mitchell: "He can claim the TMS-320 digital signal processor chip; that's the one to beat on the street right now." By 1990, TI's share of the worldwide market for general purpose DSPs was approximately 60%. A January 1991 article in Electronic Business Buyer reported that "ources say that TI has the only profitable general purpose DSP operation in the world." Rhines became CEO of Mentor Graphics in 1993, when the company's annual revenue was about $340 million. The company passed $1 billion in revenue for the first time in 2011. In 2013 Mentor Graphics announced it would begin paying a quarterly dividend, making it the only of big three electronic design automation companies to do so;. Rhines has led the company into new business areas, including providing software for the auto industry; of the big three EDA companies, analyst Tom Diffely said "Mentor has the most going on in these adjacent markets...I think is going to be a long-term huge market for them."
In memory of his father, Rhines endowed a graduate fellowship in Engineering at the University of Michigan in 2016 and a professorship at the University of Florida in 2007. He serves on the board of Classic Wines Auction in Portland, which supports a variety of children and family charities.