Functionality of a Flexible Printed Circuit

In order to ensure the functionality of a flexible printed circuit, it is important to perform both electrical and mechanical testing. For the former, this requires using automatic test equipment (ATE) to check various electrical parameters such as resistance, capacitance and impedance. Mechanical testing, meanwhile, includes measuring how well a flexible circuit board can withstand bending or twisting movements. To do this, specialized bend testers can be used to simulate different bending positions and determine whether a circuit will work as intended when bent or twisted.

Printed circuit boards are comprised of several different layers of materials, including an insulating film and conductor. They are then connected to each other through soldering and solder masks. The use of these materials allows for the creation of a flexible electronic circuit that can fold and flex, making it easier to accommodate the curves of a product’s form factor.

As the demand for a more versatile and durable electronic component rises, manufacturers are increasingly turning to flexible printed circuit to create their products. However, despite their advantages, these new types of components come with unique challenges that need to be addressed in the design and production stages. For one, they must be designed to withstand a wide range of environmental conditions, and this requires a different approach than rigid-flex PCBs.

How to Test the Functionality of a Flexible Printed Circuit

There are four main categories of flexible printed circuits, which are defined by the number of conductive layers on their dielectric substrates and the way these layers are printed. Single-sided flexible circuits are the most basic and commonly used type, featuring a single conductor layer on the dielectric and being printed only on one side. Double-sided flexible circuits are more complex, allowing access to the features on both sides of the conductive layer through plated holes. Finally, multi-layered flex circuits combine the benefits of both single- and double-sided flex circuits.

In addition to their flexibility, a key advantage of flex circuits is that they can withstand much more bending and twisting than rigid-flex PCBs. This makes them ideal for medical devices, which often need to mirror the forms of the human body, and as such require durable components that can withstand wear and tear over time.

While there are many challenges associated with the creation of a flex circuit, effective testing and quality control processes can help to mitigate these issues. To begin with, it is essential to consider just how the circuit will be used up front. This will help determine the number of layers required for each sub-stack, the type of copper and more. For example, if the circuit is going to be static and will not need to be continuously flexed, then the circuit can be made with fewer layers and less expensive materials than for a mobile device.

Choosing the right CAD software is also crucial for designing a flex circuit. Luckily, Altium Designer, part of the Altium 365 platform, offers a complete set of advanced CAD tools for tackling this complex task. Start your free trial of Altium 365 today to experience the full power of our integrated design environment.