Printed circuit boards (PCBs) are the foundational building block of most modern electronic devices.  Whether simple single layered boards used in your garage door opener, to the six layer board in your smart watch, to a 60 layer, very high density and high-speed circuit boards used in super computers and servers, printed circuit boards are the foundation on which all of the other electronic components are assembled onto.

Semiconductors, connectors, resistors, diodes, capacitors and radio devices are mounted to, and “talk” to one another through the PCB.

PCB’s have mechanical and electrical attributes that make them ideal for these applications.  Most PCB’s manufactured in the World are rigid, roughly 90% of the PCB’s manufactured today are rigid boards. Some PCB’s are flexible, allowing the circuits to be bent and folded into shape, or sometimes they are used where the flexible circuit will survive hundreds of thousands of flex cycles, without any break in the circuits.  These flexible PCB’s comprise roughly 10% of the market.  A small subset of these types of circuits are called rigid flex circuits, where one part of the board is rigid – ideal for mounting and connecting components, and one or more parts are flexible, providing the advantages of flexible circuits listed above.

A rapidly emerging PCB technology, separate from the ones above, is called printed electronics – typically very simple, very low cost, circuits that reduce electronic packaging expense to the level that electronic solutions can be developed to solve problems never considered before.  They are often used in electronics for wearable applications, or disposable electronic devices – opening many opportunities for creative electrical designers.

Conventional PCB’s can be as simple as a single layer of circuitry or can go to fifty layers or more.  They consist of electrical components and connectors linked via conductive circuits – usually copper, with the purpose of routing electrical signals and power within and between devices.

PCB’s were developed in the early 20th century but have had a continued escalated development in technology since then.  The advancement and widespread adoption of technology in PCBs has paralleled the rapid advancement in semiconductor packaging technology and has enabled industry professionals to invest in smaller and more efficient electronics.