Flexible circuit board is a special type of printed circuit board with it’s epical property of bendable feature. The demand for flexible PCBs is growing in electronic filed with especially strong demands from medical, defense and industrial markets.

Widely Application
As flexible printed circuit board can provide a great solution to connection between rigid PCBs with a reliable and repeatable electronic product. So,they have so many and wide applications that it would be impossible to completely list them all here.
Outstanding Advantages
Flex PCB provide a third dimension to connect between rigid PCB boards or to the interface between a printed circuit board and a remote electronic device, for example a sensor or a camera as in a mobile phone. They offer a light-weight solution to make the electronic product more and more lighter in weight, nearly half the weight of a rigid or a cable harness, to interconnections;as well much thinner in thickness.
Whats more, flexible PCBs are also highly robust and can be flexed numerous times without any degradation to the electronic product. In a thorough designed dynamic situation, the flex PCB can go through millions of bendable cycles, a common existing example would be on an inkjet printer head. They also have the advantage of absorbing some unexpected shock so in a small device, such as a cell phone, they can take an impact without any damage to disconnect to the circuits.
They are also widely used to mount LEDs strips for applications such as down lighters on kitchen benches, outside deck lighting, etc. And, safety lights applied in transport systems, for example planes, trains and boats all utilise LED flex strip for guide sign of the emergency exit routes.
The Cost Alert of Printed Circuit Board
Normally, the cost of flex PCBA is more expensive than a standard rigid PCB, but it can be optimized and saved by the right design and using it in the right application. Plus it’s lighter weight and less time in assembly process, coupled with the reliability which makes flexible printed circuit board a worthwhile consideration. It’s cost variations are mainly base and overlay thickness, typically 0.001” to 0.002”, different copper thickness, single or double sided plated through hole. Flex or rigid Stiffeners are an option which can help in handling during flex PCB assembly and allows electronic components to be assembled to the product easier. Another cost factors is from it’s raw material, big gap cost between famous raw material provider such as Panasonic and DuPont and normal base material manufacturer such as Taiflex.
Flex Materials
Weller Technology only uses hi-temp resistant polyimide (PI) materials unless customer insist to use low grade of material to cost down the price. Our preferred types are Panasonic and DuPont adhesivless materials, and Shengyi adhesive-based materials and coverlays.
Why Choose Weller as your flex PCB manufacturer
Weller Technology has the capability to build types 1 through 4 flexible printed circuits. Most FPC’s are designed as single-sided or double-sided, as bendability is reduced with increasing copper layers and thickness. Weller Technology has flex PCB manufacturing capability from single flex PCB to multilayer flex PCB (up to 4 layers),as well Rigid-flex.
- Single-Sided Flex
- Double-Sided Flex
- Multilayer Flex (up to 4 layers)
- Rigid-Flex (link to Rigid-Flex page)
Item | Flex PCB Capability |
PCB Layer Count | 1~6Layers |
Flexible Circuit Materials: | Dupont, Panasonic, Taiflex, Shengyi |
Min. Line Width/Space | 18um(finish Cu): 3.5/3.5mil 35um(finish Cu): 4.0/4.40mil |
Min Space Between Coverlay Opening | 0.2mm |
Edge of Coverlay Opening to Trace | 0.20mm(preferred) |
Min Space between coverlay and solder pad | 0.15mm |
Polyimide Films | 0.5 mil (12.5µ), 1 mil (25µ), 2 mils (50µ) |
Thermabond Adhesive | Thermosetting Adhesive, 3M high adhesion tape |
Copper Foils (RA or ED) | 1/3oz, 1/2oz, 1oz |
Flex Circuit Stiffeners | Polyimide, Rigid FR4, metal |
Solder Resist | Coverlay, LPI |
Min. Finished Hole size | 0.2mm |
Max. Finished Hole size | 6.30mm |
Hole tolerance | ±0.05mm |
Min.space between holes | 0.15mm |
Minimum conductor edge to outline edge | ≥0.1mm |
Minimum space between coverlay and conductor | Minimum space between coverlay and conductor |
Hole to outline edge | ≥ 0.10mm |
Tooling tolerance | Knife(Soft) tooling ± 0.25mm Steel(Hard) tooling ± 0.05mm CNC drill/rout ± 0.10mm |
Maximum Layer to Layer Mis-registration | ± 0.10mm |
Copper Plated Thickness (PTH only) | 8~15um;20~30um;30~70um(special) |
Surface Finish | Immersion Gold, Plating Hard Gold, OSP |