In 1968, three years after he emigrated from Scotland to take a job with Fairchild Semiconductor, Fullagar designed the first compensated operational amplifier. Almost 35 years later, the µA741 remains the industry standard. With its unique, fixed internal compensation capacitor, the µA741 requires no external components. But Fullagar was far from done. Subsequently, he joined Intersil as the company's first IC designer, then went on to become the company's manager of European operations and vice president of research and development. In 1983, Fullagar co-founded Maxim Integrated Products, along with Jack Gifford and Fred Beck. As vice president of R&D and vice president of applications, Fullagar was instrumental in helping Maxim to secure its position as a major contributor to the design, development, and manufacture of linear and mixed-signal ICs.