The flexible circuit, sometimes just know as the flex circuit, has been around since before World War ll. They were used in electronics equipment and military applications to replace the cumbersome and unreliable wiring harnesses used in aircraft and other equipment.
Today, you will find a flexible printed circuit in almost any electronic device you use including tablets, laptops, smartphones and all audio and video equipment. Smaller sizes of devices and the need for increasing number of components in those spaces makes the use of the flex circuit a perfect option.
There are several different types of flex circuits in use today. The specifics of the application and the location where the circuit will need to placed will narrow or expand the options.
Flat Flexible
As the name implies, this is a very thin, flat type of flexible printed circuit that is very lightweight. It can be folded to accommodate any shape, and with advanced type of printing they can be very compact. These are often used in high demand types of electronics such as copiers or printers.
The use of flat flexible circuits is on the rise in a variety of different industries. They can use standard bare copper, aluminum and tin-plated copper. They are often attached directly to the component through the use of pressure sensitive adhesives, which provide top bonding to the component even in higher temperature operating environments.
Rigid Flexible
This may sound like an oxymoron, but the rigid flexible printed circuit is actually still able to conform to different shapes, but they are thicker and stiffer than the flat flexible options.
The rigid flexible design is created by various layers of the flexible types of circuits. They are very durable and will last for years of continual use. As with the flat flexible they can be shaped to conform to different surfaces, but they are not as flexible as the flat options.
With the rigid flexible circuit, there will typically be rolled copper used in the design, and there will also be layers of acrylic and a base material, similar to the flexible designs. The materials used in these circuits can include polyester and polyimide, and it is also possible to overlay the surface of the circuit with a photo image for easy identification.
All flexible printed circuit designs offer a lightweight, versatile and durable option to a traditional circuit and wiring harness configuration. They also offer superior heat diffusion and dissipation, which is always an important consideration for electronic devices and systems.
