Math Is Fun Forum

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 51,538

Printed Circuit Board

Printed Circuit Board

Gist

A Printed Circuit Board (PCB) is a non-conductive板, typically made of fiberglass or composite epoxy, that mechanically supports and electrically connects electronic components using conductive pathways, or traces, etched from copper sheets laminated onto the board. These pathways allow electricity to flow between components like resistors, transistors, and integrated circuits, forming the foundation for electronic devices. PCBs are found in virtually all modern electronics, from computers and smartphones to appliances and more.

A Printed Circuit Board (PCB) is a fundamental component in electronics, essentially a board that provides mechanical support and electrical connections for electronic components. It acts as a base for mounting and wiring electronic components, using conductive pathways (traces) etched or printed onto a non-conductive substrate. These pathways connect components like transistors, resistors, and integrated circuits, allowing them to function as a complete circuit.

Summary

A printed circuit board, or PC board, or PCB, is a non-conductive material with conductive lines printed or etched. Electronic components are mounted on the board and the traces connect the components together to form a working circuit or assembly.

A PC board can have conductors on one side or two sides and can be multi-layer — a sandwich with many layers of conductors, each separated by insulating layers.

The most common circuit boards are made of plastic or glass-fiber and resin composites and use copper traces, but a wide variety of other materials may be used. Most PCBs are flat and rigid but flexible substrates can allow boards to fit in convoluted spaces.

Components are mounted via SMD (surface-mount) or through-hole methods.

Details

A printed circuit board (PCB), also called printed wiring board (PWB), is a laminated sandwich structure of conductive and insulating layers, each with a pattern of traces, planes and other features (similar to wires on a flat surface) etched from one or more sheet layers of copper laminated onto or between sheet layers of a non-conductive substrate. PCBs are used to connect or "wire" components to one another in an electronic circuit. Electrical components may be fixed to conductive pads on the outer layers, generally by soldering, which both electrically connects and mechanically fastens the components to the board. Another manufacturing process adds vias, metal-lined drilled holes that enable electrical interconnections between conductive layers, to boards with more than a single side.

Printed circuit boards are used in nearly all electronic products today. Alternatives to PCBs include wire wrap and point-to-point construction, both once popular but now rarely used. PCBs require additional design effort to lay out the circuit, but manufacturing and assembly can be automated. Electronic design automation software is available to do much of the work of layout. Mass-producing circuits with PCBs is cheaper and faster than with other wiring methods, as components are mounted and wired in one operation. Large numbers of PCBs can be fabricated at the same time, and the layout has to be done only once. PCBs can also be made manually in small quantities, with reduced benefits.

PCBs can be single-sided (one copper layer), double-sided (two copper layers on both sides of one substrate layer), or multi-layer (stacked layers of substrate with copper plating sandwiched between each and on the outside layers). Multi-layer PCBs provide much higher component density, because circuit traces on the inner layers would otherwise take up surface space between components. The rise in popularity of multilayer PCBs with more than two, and especially with more than four, copper planes was concurrent with the adoption of surface-mount technology. However, multilayer PCBs make repair, analysis, and field modification of circuits much more difficult and usually impractical.

The world market for bare PCBs exceeded US$60.2 billion in 2014, and was estimated at $80.33 billion in 2024, forecast to be $96.57 billion for 2029, growing at 4.87% per annum.

Additional Information

Printed circuit boards are made from a variety of PCB materials and electrical components. Common PCB components include:

Resistors

Resistors transmit an electrical current to produce a voltage and dissipate electric power as heat. They come in a range of materials.

Capacitors

The job of a capacitor is to hold an electrical charge within the board and then release it when more power is needed elsewhere in the circuit. Capacitors typically work by collecting opposite charges on two conductive layers that are separated by an insulating material.

Inductors

These are similar to capacitors in that they store energy. However, they are often used to block signals within the PCB, such as interference from another electronic device.

Transistors

A transistor is an amplifier. It’s used to switch or control the electronic signals in a board. There are several different versions of transistors available, but the most common is the bipolar transistor.

Transformers

These are used to transfer the electrical energy from one circuit to another via an increase, or decrease, in voltage.

Diodes

A diode allows the electric current to flow in one direction, but not in the other. As a result, diodes are used to stop the electric current from flowing in the wrong direction and damaging the board and the device. The most popular form of diode is the LED (which stands for light-emitting diode). 

Sensors

These devices are used to detect changes in environmental conditions and generate an electrical signal that corresponds to the change. This signal is then sent to other components in the circuit board. Sensors convert a physical element such as light motion, air quality, or sound into electrical energy.

---

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.