The Origin of Printed Circuit Boards: A Look Back in Time

The printed circuit board (PCB), like many groundbreaking inventions, was built on a foundation of historical progress. Over 140 years ago, between 1880 and 1900, the spread of electricity transformed daily life, replacing traditional fuels and powering homes. Key electromagnetism and motor-related innovations during this period laid the groundwork for PCBs and their role in electronics manufacturing. To know more about PCB manufacturing see our latest article on PCB manufacturing process. Notable inventions of the era include:

• Thomas Edison: Light bulb (1879)
• Nikola Tesla: Motor (1888) and AC power supply (1895)
• Alexander Graham Bell: Telephone (1876)
• Kodak: First camera (1884)
• Herman Hollerith: Tabulating machine (1890), leading to IBM

Though PCBs emerged later, their development owes much to the technological strides of this transformative era. PCBs in their modern form have been around since the 1960s, when they were components in calculators, cash registers and other simple devices with electrical circuits.

Early Beginnings: Pre-PCB Era

Before PCBs, electronic circuits were assembled using point-to-point wiring. Components were soldered to terminal strips or boards, leading to bulky, fragile, and unreliable designs. The growing complexity of circuits in the early 20th century demanded a more robust and efficient solution.

Development in Past 80 Years:

Printed circuit boards (PCBs) are vital components in countless electronic devices and computer systems

• 1950s-1960s: Introduction of multilayer PCBs and plated-through holes allowed for more compact designs.
• 1970s: Computer-aided design (CAD) revolutionized PCB design, increasing precision and efficiency.
• 1980s: Surface-mount technology (SMT) enabled smaller components and higher assembly densities.

Their modern design dates back to the 1960s, initially found in calculators, cash registers, and other basic electronic devices. In the 1970s, PCBs began appearing in digital watches and some of the world’s first video games and personal computers. By the 1980s, PCBs were in alarm radios, video cassette recorders, Atari game consoles, CD and laserdisc players and cordless phones. During the 1990s, an increasingly advanced and miniaturized PCB was responsible for the spread of desktop computers and peripheral devices like scanners and printers.

Since the late 1990s, the rapid evolution of technology has led to smaller, more powerful PCBs. Modern devices like smartphones exemplify this trend, offering compact designs with enhanced durability and functionality. Today’s PCBs feature flexible substrates, high-frequency designs, and advanced materials like PTFE and ceramics, catering to diverse industries from IoT to aerospace. Innovations like 3D printing and AI-assisted design continue to push boundaries.

Why PCBs?

Printed circuit boards (PCBs) are fundamental to modern electronics, offering a compact and reliable platform for connecting components. By replacing complex wiring with conductive pathways, they ensure efficient signal and power transmission. PCBs support miniaturization, provide mechanical stability, and enable high-speed applications, making them vital for everything from simple gadgets to advanced systems. Their durability and cost-effectiveness further underscore their importance.

Over time, the evolution of technology and PCB design has been astounding. While a calculator might house 30 transistors, modern motherboards integrate over a million transistors on a single chip. This progress reflects key trends in PCB manufacturing:

• Increased Functionality in Smaller Components: Integrating more functionality into smaller components, such as ICs and microprocessors.

• Miniaturization of Passive Components: Shrinking passive components like resistors and capacitors to microscopic scales.

• Higher Component Density and Complexity: Increasing the density and complexity of components on the board.

These advancements are driven by growing demands for faster, more functional devices, reflected in everything from high-speed electronics to realistic video games, showcasing the rapid pace of innovation.

The Story of Paul Eisler's and The Birth of PCBs

The concept of PCBs was first patented in 1903 by German inventor Albert Hanson, who described flat foil conductors laminated onto an insulating board. While his idea was ahead of its time, it wasn't until 1943 that PCBs became practical. A pivotal moment came in 1943 when Austrian engineer Paul Eisler developed the first operational PCB while working on a radio set. During World War II, the U.S. military adopted PCBs for compact, reliable radio systems, sparking widespread use. The printed circuit board (PCB) is probably one of the most important inventions of the 20th century. The intellectual father of the printed circuit board was Paul Eisler.

How Eisler got Idea of PCBs

The construction of the radios of that time used tubes, resistors and coils that were still connected with individual wires. A tangled mass of wires was created in the radios of that time, which was complex and confusing to follow. Eisler, on the other hand, wanted a clean system of conductor lines on one level. Something that could be printed, something that would be the basis for a mass production process.

Eisler, who studied engineering, had worked as an editor of a magazine during his studies. Even then, printing on paper gave him the idea that this process should enable more than just the mass production of newspapers. Eisler experimented vigorously and registered his first patent in 1936, a precursor to his main patent that describes the first real printed circuit board. He presented his idea to the English radio manufacturer, but in their opinion connecting wires is cheaper and flexible so they rejected him and his idea.

Transferring Rights to Strong

In 1939, at the onset of the war, Eisler found a supporter in Harold V. Strong, a wealthy printing house owner. Recognizing the potential of Eisler's printed circuit board concept, Strong saw an opportunity to shift from the struggling printing industry, facing a paper shortage, to the booming arms industry. During a taxi ride, Eisler confidently signed a contract, transferring the rights to his invention to Strong for just one English pound.

How PCBs got mass Fabricated:

Although the military potential of the invention was clear, the British Ministry of Defence opposed its use. As a result, no private company in Britain was willing to develop it further. In contrast, the Americans took a different approach. The British often reported their inventions to the American Bureau of Standards, and there, a printed circuit board was developed for use as a proximity fuse in air defense projectiles. This innovation allowed electronics to be produced in large quantities at a low cost.

PCB to Public:

In 1948, other than the Military, the public also learned about the idea of the printed circuit. The triumphant march of the printed circuit board began, especially since the principle of mass soldering by solder wave was developed at that time. This was another important prerequisite for low-cost mass production of electronics.

Eisler's invention did not bring him significant success, nor did Harold V. Strong achieve the financial gains he had initially anticipated. Strong's company, Technograph, focused on marketing licenses for printed circuit boards. Despite Eisler serving as a board member, he never became wealthy, as a monopoly on printed circuit boards was never established.

Today, countless quantities of printed circuit boards are produced all over the world. Even though they are getting smaller and smaller, a modern mass production of electronic devices would be unthinkable without the printed circuit board.

Popularity of PCB

The US military was the first to apply PCB technology, as the PCB invented by Eisler was affirmed by the military and used in military radios during World War II. The United States and the United Kingdom collaborated to develop circuit boards, and the technology was used in military weapons during the war. The American electronics industry embraced the concept of the printed circuit board in the 1950s, quickly advancing its development. By the mid-1950s, the innovation returned to Europe, with German companies beginning production in 1957.

The United States officially recognized PCB technology in 1956, and the US Army published the first patent for the “circuit assembly process.” PCB manufacturers have since developed various assembly techniques to secure electronics and make electrical connections between components with copper traces.

Eisler was not recognised as the Inventor of PCB for 35 years

Eisler, who initially remained on the board of Technograph, departed from the company that same year. While he was less concerned about his lack of financial success, he deeply regretted not receiving the recognition he deserved as the creator of one of the century's most impactful inventions.

It wasn’t until 1971 that Eisler was officially acknowledged as the inventor of the printed circuit board. In 1992, shortly before his death on October 26 at age 85 in a London suburb, the Institute of Electrical Engineers honored him with the Nuffield Silver Medal.

Other inventions of Eisler

In addition to his world-famous invention of the printed circuit, Paul Eisler invented other important products for electrical engineering. Among other things, he applied for patents for electrical fuses, for multilayer materials or for a foil battery.

Without printed circuitry we would not be able to communicate with mobile phones, have television reception, play on the computer or surf the Internet. Cheap and affordable electronics are now available thanks to Paul Eislers invention.

The Environmental Shift

With the rise of consumer electronics, environmental concerns surrounding PCB manufacturing led to the adoption of RoHS (Restriction of Hazardous Substances) compliance. This ensured safer materials and sustainable production practices. And to order these PCB board from a manufacturer you need a specific file format, to know more about PCB file format see our latest blog in detail.

Conclusion:

Like many other great inventions in history, the printed circuit board (PCB) that we know today was built on a foundation of advancements throughout history. In our little corner of the world, we can trace the history of PCBs back over 140 years. From their rudimentary origins to the cutting-edge designs of today, PCBs remain a cornerstone of modern electronics, shaping the future with every innovation. What we cover in this article is not a complete history but rather the sweeping moments that transformed PCBs into what they are today.