Dov Frohman - Inventing The EPROM

Inventing The EPROM

After graduating from the Technion in 1963, Frohman traveled to the United States to study for his masters and Ph.D. at the University of California, Berkeley. After receiving his masters in 1965, he took a job in the R&D labs of Fairchild Semiconductor, a breeding ground of many early Silicon Valley firms. In 1969, after completing his Ph.D., he followed former Fairchild managers Gordon Moore, Robert Noyce, and Andrew Grove to Intel Corporation, which they had founded the previous year.

It was while troubleshooting a fault in an early Intel product that Frohman in 1970 developed the concept for the EPROM, the first semiconductor memory that was both erasable and easily reprogrammable. At the time, there were essentially two types of semiconductor memories. Random-access memory (RAM) chips were easy to program, but a chip would lose its charge (and therefore, the information encoded on the chip) when its power source was turned off. In industry parlance, RAM chips were volatile. Read-only memory (ROM) chips, by contrast, were nonvolatile—that is, the information encoded in the chip was fixed and unchangeable. But the process for programming ROM memories was time-consuming and cumbersome. Typically, the data had to be “burned in” at the factory: physically embedded on the chip through a process called “masking” that generally took weeks to complete. And once programmed, the data in the ROM chip could not be altered.

The EPROM combined the best of both worlds. Like ROM, it was nonvolatile. But, like RAM, it was easily reprogammable. It was the catalyst for a whole line of innovation and development that eventually led to today’s ubiquitous flash memory technology. The EPROM was also a key innovation in what became the personal computer industry, one that Intel founder Gordon Moore has termed “as important in the development of the microcomputer industry as the microprocessor itself.” It remained Intel’s most profitable product well into the 1980s.