Our lives would be very different without printed circuit boards. The boards show up in many of the items that we rely on every day. From coffeemakers, refrigerators, and microwaves, to computers, TVs, and automobiles, the boards really do get us through our days.
What are PCBs?
Stated by a PCB assembly company, printed circuit boards (PCBs) show up in domestic and industrial electronics. The boards are covered with circuits and components that connect different parts of the device so they could work properly. These little boards become the brain of the device. Each board is so precise that some devices have more than one.
The first PCB was created by Paul Eisler, who put it on a radio in 1936. Since then, the small fiberglass or plastic boards have advanced significantly. Consider that most smartphones today have at least two complex PCBs in them, as one controls the phone while the other controls the camera. Some also have another PCB that controls the touchscreen.
Today’s PCBs are flat and rigid boards, and many have two or more layers to contain all of the components and etched pathways. They usually have copper pathways that carry the electrical current through the components.
Printed circuit boards are technically not printed. Instead, they are etched. They have a copper foil placed over the board, then covered in a material called photoresist. To etch the copper in place, light is put through the negative, so the photoresist hardens in the pathways. Later the unhardened photoresist washes away. If there are several layers, they are glued together. Then, the components are added.
PCBs in Computers
All types of computer hardware rely on PCBs not just to work properly, but to connect to other types of hardware. It is impossible to build a computer without using at least one PCB, and many have several of them so they can connect to printers and other peripherals.
The most common color for a PCB is green, but they can be other colors based on the type of solder mask that is used to put the etched traces and the components into place. The most complicated and important PCB on a computer is called the motherboard or system board. Other computer hardware connects to the motherboard through expansion cards and flexible circuits that connect through the USB ports and other slots.
Consider that PCBs help computer peripherals connect wirelessly. Your wireless router and your video game system connect with a PCB. So do your mouse and any other small devices you use to work your computer.
The new PCBs need to be able to withstand the heat that emanates from today’s speedy computers. Devices with LEDs run extremely hot, so the PCBs have added thermal conductivity, so they do not overheat. Consider how different PCBs need to fit into specific spaces. Your smartwatch has a significantly smaller PCB than your laptop computer.
PCBs for computers and hardware come in different materials. The rigid-flex boards are still ubiquitous. But, PCB manufacturers are using aluminum, ceramic, and other metals.
PCBs in Various Industries
As computers are heavily used in several industries, the PCBs have to help the devices do their jobs.
Medical Computers and Devices
Consider how computers are used in the medical industry. Yes, health care providers use traditional computers, but they also rely on specific devices for monitoring, diagnosing, and treating patients. Therefore, the PCBs need to be able to meet those needs while meeting sanitary standards, too. Some PCBs are even used in implants that are put into the human body.
Automobiles and Components
It is tough to find a modern car that does not have a PCB in it. The earliest uses of PCBs in cars were to power wipers and headlights. Now they are used to monitor exhaust, control gas use, and manage the safety features. PCBs used in automotive computers need to withstand environmental elements such as extreme hot and cold temperatures. They also need to resist the vibration and impacts that come with driving.
PCBs in automobiles and trucks control navigation systems, entertainment systems, sensors, and more. Some PCBs run the entire car – consider the self-driving cars. And, some can help traditional cars parallel park automatically.
Aerospace Applications
If you have ever flown, you may have seen PCBs as you entered the airplane. Aerospace PCBs need to be able to resist even more extreme temperatures and vibrations than automobiles. Some even have to withstand the vacuum of space, as PCBs are inside of satellites that orbit the Earth.
Aerospace PCBs are used for powering planes, control towers, and systems. They are also used to monitor aircraft, and they are used for communication between pilots and ground control.
Military and Defense Devices
Printed circuit boards are also used in military devices. These PCBs need to be reliable because they are used in devices that protect people. They also need to be durable because they are transported to harsh climates. Many are made of aluminum and copper because those metals are resistant to oxidation.
PCBs are used in military and defense devices like radio communication systems, missile detection systems, and instrumentation. Since the military is often the leader in technology, PCBs might be used in ways that civilians have yet to imagine.
Industrial Devices
In the industrial sector, PCBs are used in a wide range of devices. They are made in several industries, and most industries rely on technologies that are filled with them. PCBs need to be durable enough to tolerate the harsh environments inside these industrial facilities. Industrial-grade PCBs are often thicker than PCBs used in desktop computers, and they are made with more durable materials. The PCBs are put into manufacturing, power, and measuring equipment. They are also being placed into robots that are becoming more common in industrial settings.
