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Printed circuit boards are common parts found in most modern electronic devices. They are inexpensive, easy to repair, and recyclable. They are widely used in computers, printers, and even cell phones. If you want to learn more about circuit boards, keep reading. You can learn how to spot the right ones, and where to find them.
Printed circuit boards are used in most modern electronic devices
Circuit boards are the basic building blocks of most modern electronic devices. They are used for various functions and come in a variety of shapes and sizes. Some boards are populated with components directly on the surface, while others use pre-drilled holes for larger components. Regardless of the method used to install electronics, PCBs are a crucial part of modern technology.
Before printed circuit boards were developed, most electronic devices used a different approach: point-to-point construction, in which wires were soldered directly to the components. This method had its drawbacks, however. It was slow and difficult to mass produce and was not ideal for handling delicate electronic components.
Printed circuit boards come in two types: single-sided and multi-layer. Single-sided PCBs have a single layer of copper, while double-sided PCBs have two copper layers and are sandwiched between two layers of substrate. Both types are flexible and bendable, and can be easily folded in half. They are also categorized according to how many copper layers are on each layer. Multi-layer PCBs have four or more conductive layers, allowing for more routing options and improved functionality.
They are easy to repair
PCBs are made of several layers of copper and fibreglass. If they get damaged, solder can be used to repair them. However, PCBs can become overheated and the copper layer can de-laminate from the fibreglass board. This can cause the joints to break. If you’ve got an overheated PCB, you can try a different method to repair it.
The first method involves chemically applying a potassium permanganate-based etchant. The resultant solution will dissolve glass fibers and resin from the board. The copper layers on the board will then be extended into the hole, making them integral to the board. However, this is only possible if you have the right tools to repair the board.
The second technique involves re-soldering the board. In many cases, a bad soldering job or cheap components can cause a PCB to malfunction. This can lead to poor connectivity and poor performance. In such cases, a new PCB might be required.
They are economical
Circuit boards are economical in several ways. The first, of course, is the material cost. While price lists and datasheets provide some guidance, there is no direct relation between raw material cost and board yield. Some materials are cheaper than others, while others require more expensive processing. Further, raw prices are usually not related to cost-of-fabrication.
The second, and less-intuitive, reason is the type of material used. The most common material is FR-4, a dielectric composite material containing a polymer resin matrix and reinforcement, usually nonwoven glass fibers or paper. Some materials also contain titanate ceramics, which increase dielectric constant.
Moreover, thermosetting resins can be inexpensive. Epoxy, for instance, is widely used in electronic circuit boards. It has excellent electrical, mechanical, and thermal properties. Epoxy can be cured using catalysts and hardeners. However, it is flammable, so flame retardants are often used to reduce its flammability. However, these chemicals are not effective for organic chip packages and cannot be used in marine and industrial environments.
They are recyclable
The printed circuit board (PCB) is the main component in making electronic gadgets. It consists of a thin layer of copper on which a chip or other component is placed. These components are connected by traces that run along the board. When we discard an old electronic gadget, we are also discarding a PCB. This is bad for the environment, as PCBs are comprised of precious metals. The recycling process helps to conserve these materials and reduce their consumption.
Although circuit boards are recyclable, they do contain a variety of toxic metals and other dangerous materials. Among these are lead, tin, and zinc. They also contain small amounts of aluminum, copper, and nickel. Moreover, they contain a few hazardous elements, including phthalates, which are linked to cancer and damage to the liver and kidney.
It is important to recycle electronics when they are no longer in use. Only fifteen to twenty percent of all electronic waste is recycled in the U.S. The rest of electronic waste is burned or incinerated, releasing toxic materials and harmful elements. Many circuit boards also contain chemicals such as brominated flame retardants, which are known to cause cancer and reproductive disorders.