Next up in our series of Rochester Electronics’ favorite 1970s semiconductors is Intel’s 4004 CPU.

Have you ever considered how many microcontrollers and microprocessors you interact with each day? The number of micros embedded in everyday products has exploded over the past few decades and the fact is that it’s difficult to keep track of them all. This was not always the case though, which brings up the question, just when did the use of micros in commercial products start?

One could look to 1969 when Busicom worked with Intel on the chip designs for their electronic calculators. This partnership resulted in the creation of 4004 CPU. Intel, which had only been founded a year earlier, was still a small and upcoming company. However, with the creative talents of engineers such as Ted Hoff, Stanley Mazor, Frederico Faggin, and Busicom’s Masatoshi Shima, the project had the team needed to capitalize on recent technology advancements.

The team faced many of the same challenges designers face today, only on a far different scale. The 4004 provided advancements in integration during this era, but it was not the complete solution that is found in modern micros. Intel’s choice at this time was a multi-chip design comprised of 4 separate ICs. It was based on a 4-bit CPU architecture, built using 2,300 transistors. The initial proposal had been for a 7-chip solution, but concerns over pin count, packaging, and costs, lead to a new design, bringing the count down to 4 chips and allowing the use of a more cost-effective 16-pin dual in-line package (DIP).

The design was a chipset made up of the 4001 ROM program memory, the 4002 RAM memory, the 4003 interface IC and the 4004 CPU.