Who Invented the CPU? Let’s explore CPU history!

by Arslan Ashraf

Who Invented the CPU? Let’s explore CPU history!

One of the most important engineering achievements of all time is the creation of the microprocessor. Many people have claimed to be the creator of it, although there is no universally accepted meaning of the term. When the term “microprocessor” was initially used, it referred to a computer that used a microprogrammed architecture, a method that Maurice Wilkes initially introduced in 1951. In 1968, Viatron Computer Systems introduced the term “microprocessor” to characterize its small-business-oriented System 21 machines. 

The term “microprocessing unit” or MPU is now used to refer to the silicon component of computers that handles all of the crucial logical functions in a computing system. It is described as a “computer-on-a-chip” in common media reports. Moreover, now, it’s capable enough to deal with colossal processing requirements. When the chip has so much importance, a question arises, who invented the CPU, an impactful invention of all time? Well, in this post, we will see all the evidence we collected from numerous resources to solve the query. 

Some Early Inventions that Helped in Creating CPU

Development of Computer Chips

Three fundamental functional building pieces make up a general-purpose computer. The central processor unit (CPU), which performs both arithmetic and control logic operations, a storage unit for holding programs and data, and I/O units (UART, DMA controller, timer/counters, device controllers, etc.) that interface with external devices like monitors, printers, modems, etc. In a 1964 IEEE publication, Ed Sack and other Westinghouse engineers reported an early attempt to combine many transistors on a silicon chip to make a CPU.

To achieve multiple-bit logic operations on a single piece of silicon, they claimed that “techniques have been established for the connectivity of a large number of gates on an integrated-circuit wafer”. In the end, it seems possible to implement a sizable chunk of a computer arithmetic function on a single wafer. The Texas Instruments SN7400 family of standard integrated circuit (IC) logic chips, which were installed on various printed circuit boards, made up the majority of compact computer systems at the time (PCBs). 

Creation Of MOS-LSI (large-scale-integration)

As IC production techniques switched from bipolar to metal oxide Semiconductor (MOS) technology, a significant step toward the Westinghouse engineers’ objective of fitting a CPU on a single chip was made. Large-scale integration (LSI) chips with hundreds of logic gates were made possible by MOS by the mid-1960s. Custom LSI chips were created by designers of consumer digital products where compact size was an advantage, such as in watches and calculators. 

Small LSI-based computer systems, also known as microcomputers, started to appear in the early 1970s. The designers of these machines adopted the strategies utilized by calculator manufacturers to decrease the number of chips needed to build a CPU by producing more densely packed LSI ICs. These were referred to as microcomputer chipsets, and a computer system could be created by combining all of the LSO chips. So these are the beginning steps that ultimately led to a more complex design.

Who made the First CPU?

Fairchild Semiconductor started developing these components to establish standardized MOS computer systems in 1966. Its first fully functional CPU processor bit slice, the 3804, included instruction decoding, a parallel four-bit ALU, registers, full condition code generation, and the first implementation of an I/O bus. Although without internal multi-state sequencing capability, it would not be regarded as a microprocessor, according to designer Lee Boysel, it was a significant step in defining the architectural features of future microprocessors. 

In 1968, Boysel started developing the AL1, an 8-bit CPU bit slice intended for use in low-cost computer terminals. In April 1969, after establishing Four Phase Systems Inc., he finished the design and exhibited functional chips. A multi-terminal server needed three AL1 devices, compared to one for a single terminal arrangement. Fairchild Semiconductor kept investing in this field even after Boysel departed the firm with the PPS-25 (Programmed Processor System), a series of 4-bit programmable chips unveiled in 1971.

When did Intel make its first CPU?

The MCS-4 Micro Computer Set, Intel’s first attempt in this market, was designed to be the most effective way to manufacture a set of calculator chips. The 4004 was the centerpiece of the four-chip set, developed in January 1971 by a group of logic architects and silicon engineers for the Japanese calculator maker Busicom. The 4004 was first referred to as a 4-bit micro programmable CPU. It is now referred to as a “single-chip 4-bit microprocessor” in a later data sheet.

The 4004 CPU device, one of the densest chips made to date, contains 2,300 transistors thanks to a revolutionary silicon-gate MOS technique developed by Faggin and Shima. Compared to earlier systems, this complexity packed more of a processor’s crucial logical components onto a single chip. The ALU, data registers, a program counter, instruction decode/control logic, and the data pipeline connecting those components were among them.

What are the Applications of CPU?

A microprocessor simplifies daily living with its low price, low power, tiny size, and wide range of applications across many industries. Microprocessors are used in a variety of applications where these act as brains in different machines. For example, the microprocessor(s) is/are given in the computer, laptops, watches, and mobile phones to perform specific tasks. It supervises the overall performance of the system while controlling every in and out of the computing device. 

Other than that, it’s used by:

  • Devices for the Home Industrial Uses of Microprocessors
  • The transportation sector
  • Electronics and computers
  • Instrumentation in the Medical
  • Embedded Entertainment Systems for the Home
  • Publication and Office Automation
  • Communication


The microprocessor has the same importance as the invention of the wheel. It has revolutionized the tech ecosystem as the wheel modernized transport systems. But if we look at who invented the CPU, we get several answers. Maybe since it relies on how various subject-matter specialists define the term, microprocessor, and its uses. Technology expert Nick Treddenick claims that Boysel made the first CPU and his AL1 model was the first CPU in existence. That is to say, the first model was as similar to a CPU as we have now. But Gordon Bell defended his viewpoint in a CHM video shot in 2010. 

Most historians investigating the complex history of the microprocessor’s invention conclude that it was just a concept whose time had come. Many semiconductor companies worked to increase the number of transistors that could be put onto a single silicon chip throughout the 1960s. In line with this, several commercial and government-funded computer designers sought to lower the number of chips in a system. It was inevitable and evident that the primary operations of a CPU would eventually be implemented on a chip.

Frequently Asked Questions

Who developed the computer processors?

Well, it’s challenging to find the creator of computer processors since we got several names in our research. But according to most discoveries, the first processor chip was developed by Fairchild Semiconductor in 1966 for some standardized MOS computer systems. It’s called the “3804 chip” that comprises a decoder, four-bit ALU, registers, an I/O bus, and a code generator.

Did Intel create the CPU?

Fairchild Semiconductor created the first processor in 1966, according to most of the historical data. But, the first commercial microprocessor chip, Intel 4004, was definitely manufactured by Intel with the help of Ted Hoff on 5 November 1971.

What is the CPU made up of?

A CPU, or central processing unit, is an electronic circuitry executing particular computing instructions. Structure-wise, it consists of primary storage to store instructions, a control unit, and an arithmetic and logic unit (ALU) to perform processing operations.

Arslan Ashraf

Arslan Ashraf is a tech enthusiast and an experienced technical writer at GamingDairy. He has been writing all types of guides, tutorials, and tips for gamers, developers, and other people who use computers. His way of writing is quite unique: he starts with testing every single piece of Hardware and does a long list of experiments before writing the actual masterpiece. Well, if you have any queries, ensure to connect with him!