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Chip Hall of Fame: Zilog Z80 Microprocessor

Another legend from the 8-bit era, this processor powered the first portable computer as well as the beloved “Trash-80”

2 min read
Zilog Z80 Microprocessor
Image: Computer History Museum

Zilog Z80 Microprocessor Image: Computer History Museum

Z80 Micro-processor

Manufacturer: Zilog

Category: Processors

Year: 1976

Federico Faggin knew well the kind of money and man-⁠hours it took to market a microprocessor. While at Intel, he had contributed to the designs of two seminal specimens: the primordial 4004, and the 8080, of Altair computer fame. So when Faggin founded Zilog with former Intel colleague Ralph Ungermann, they decided to start with something simpler: a single-chip microcontroller.

But the engineers soon realized that the microcontroller market was crowded with very good chips. Even if theirs was better than the others, they’d see only slim profits. Zilog had to aim higher on the food chain, and the Z80 microprocessor project was born.

The goal was to outperform the 8080 while offering full compatibility with 8080 software, to lure customers away from Intel. For months, Faggin, Ungermann, and Masatoshi Shima, another ex-Intel engineer, worked 80-⁠hour weeks hunched over tables, drawing the Z80’s circuits. Faggin soon learned that when it comes to microchips, small is beautiful but it can hurt your eyes.

“By the end I had to get glasses,” he says. “I became nearsighted.”

The team toiled through 1975 and into 1976. In March of that year, they finally had a prototype chip. The Z80 was a contemporary of MOS Technology’s 6502, and like that chip, it stood out not only for its elegant design but also for being dirt cheap (about US $25).

The Z80 ended up in thousands of products, including the Osborne I (the first portable, or “luggable,” computer), the KayPro II, the Radio Shack TRS-80, and MSX home computers, as well as printers, fax machines, photocopiers, modems, and satellites. Zilog still makes the Z80, which is used in some embedded systems.

Photo:

An early Z80 chip in a ceramic package. Mass produced version used a plastic package.

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The Godfather of South Korea’s Chip Industry

How Kim Choong-Ki helped the nation become a semiconductor superpower

15 min read
A man in a dark suit, bald with some grey hair, leans against a shiny blue wall, in which he is reflected.

Kim Choong-Ki, now an emeritus professor at Korea Advanced Institute of Science and Technology, was the first professor in South Korea to systematically teach semiconductor engineering.

Korea Academy of Science and Technology
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They were called “Kim’s Mafia.” Kim Choong-Ki himself wouldn’t have put it that way. But it was true what semiconductor engineers in South Korea whispered about his former students: They were everywhere.

Starting in the mid-1980s, as chip manufacturing in the country accelerated, engineers who had studied under Kim at Korea Advanced Institute of Science and Technology (KAIST) assumed top posts in the industry as well as coveted positions teaching or researching semiconductors at universities and government institutes. By the beginning of the 21st century, South Korea had become a dominant power in the global semiconductor market, meeting more than 60 percent of international demand for memory chips alone. Around the world, many of Kim’s protégés were lauded for their brilliant success in transforming the economy of a nation that had just started assembling radio sets in 1959 and was fabricating outdated memory chips in the early ’80s.

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