A Guide To The Fundamentals Of Flex PCBs
PCBs or printed circuit boards are self-contained boards with interconnected electronic or electrical components. Printed circuit boards find their place in beepers, pagers, radar, radios, computers, smart-watches, smartphones, and more. Manufacturers create them by producing a slight layer of conducting material positioned on the outsides of an insulating board. This conducting substance is the one that you know as the substrate. Manufacturers place separate components on the surface of the substrate and then solder them to the connected circuits. There are three ways to produce a printed circuit board. They are single-sided, double-sided, and multi-layered. The components of a PCB connect with each other by two methods; hole technology and surface mounting.
- Single-sided flex circuits: There was a time when PCBs used to be rigid and inflexible. Now, manufacturers produce such circuit boards which are bendable. The first one on the list is the single-sided flex circuit. A single-sided flexible PCB isn’t necessarily a multiple flexible circuit. It contains a layer of conductor made of metal or metal-filled polymer on a flexible dielectric film.
- Double-sided flex circuits: As the name suggests, double-sided flex circuits possess two layers of conductors. Manufacturers can fabricate them with or with plating them through holes. However, the plated through holes version is the more common one available in the market. You can say that a double-sided flex circuit is a multiple flexible circuit. When manufacturers produce them without plating-through-holes, it is possible to access the association features from one side only.
- Sculptured flex circuits: Sculptured flex circuits are a unique version of the typical flexible PCBs. The developed procedure of creating such wiring involves the use of a particular flex circuit. Apart from that, manufacturers use a multi-step etching method which yields a sculptured flex circuit. They contain copper conductors, and the thickness of the conductors differs in several areas along the length of the board.
- Multi-layer flex circuits: Flex circuits with three or more layers of conductors are multi-layer flex circuits. Typically, manufacturers connect all the layers utilizing plated-through-holes. Though, not every multi-layer flex circuit is the same. Manufacturers can supply openings to access lower circuit level features. A multi-layer flex circuit doesn’t need continuous laminations.
- Rigid-flex circuits: Rigid-flex PCBs are a hybrid with both rigid and flexible substrates. Manufacturers laminate them mutually into a single structure. You shouldn’t misunderstand between a rigid-flex circuit and rigidized flex constructions . They are flex circuits where producers apply a stiffener to maintain the weight and balance of the electronic apparatus. A stiffened flex circuit may contain one or several extra conductor layers.
The purpose of flex circuits
Flexible circuits are highly purposeful, especially in today’s time. They serve as connectors in many applications where flexibility is crucial. It also prevents electronic devices from consuming more space. They are useful in constructing anything where rigid PCBs fall short. If you can make it using plastic or metal foil as the substrate, then the whole system becomes bendable. You will find flexible circuits in passive wiring structures with which you can interconnect electronic components.