Flex and Rigid-Flex PCBs

PCBs with the ultimate versatility

Rigid-Flex and Flex PCBs will all be built with a level of flexibility. A Flex circuit will be completely flexible and a Rigid-Flex circuit will consist of two or more rigid boards connected with a dynamic flexible join.

The ability of these boards to fit into tight spaces when no other solution would work, is often considered as their primary benefit, but they also have a lot of other benefits.

Rigid Flex PCB Animation


The terms FPC (Flexible Printed Circuit), Flex Circuit Boards, Flex PCBs, Flex Circuits, and Flexible Printed Circuits are also used to describe flexible printed circuits. They consist of a conductor circuit enclosed in a thin coating of insulating polymer. Polyimides are widely used in construction because they allow for high temperature assembly or product environments. Flex circuits can be produced as a connection or with a component-use design. Stiffeners that are rigid may be used. They can be built with one side, two sides, or multi layers.

Rigid Flex

Rigid Flex boards are hybrid boards that, by definition, combine a Flex board with a rigid circuit component. These hybrid circuits can consist of two or more rigids connected by Flex circuits, a Flex with a FR4 stiffener, or both. Rigid Flex circuits combine the best features of rigid boards and flexible circuits onto a single PCB.

Rigid Flex circuits are incredibly adaptable and have a wide range of uses. Designers frequently believe that they are the best option for utilising the packing space that is available.

This technique is also motivated by improved product dependability and overall lower assembly costs.

Advantages include:

  • Lower weight
    Flex construction materials like polyimide is substantially lighter than standard substrates. The omission of standard connectors also help reduce weight. This technology is often used in wearable or products that need to be carried.
  • Lower cost
    The use of thin polyimide films that can be bent means smaller packaging can be used resulting in lower product prices. Lower box build costs are also possible because to quicker assembly and fewer connectors.
  • Dynamic Flex
    Standard Flex and Rigid-Flex are only flexed during installation. As Dynamic Flex boards can bend repeatedly, they can be used for computers, robots, printers etc.
  • A more reliable product
    By eliminating the requirement for conventional connectors, dependability with regard to assembly problems or connector failures can be increased. The thermal stability of the circuits is also improved with the use of polyimide materials.
  • Maximum utilisation of packaging space
    Being thin and flexible makes these circuits simple to fold, crease, and bend to fit even the smallest areas where rigid boards would not fit. They are also perfect for being formed into the geometry of 3D packaging solutions.
  • Ideal for high vibration environments
    Extremely shock resistant.
Flex and Flex-Rigid Manufacturing Capabilities
    Standard Advanced Comment
FCCL (adhesiveless) IPC-4203/11 25µm, 50µm 75µm 100um  
Copper   0.5oz(17µm), 1oz (35µm) 2oz (70µm)  
Coverlay IPC-4203/1 Adhesive 25µm, 50µm, 75µm   Colour: Amber
Flex Solder Resist   Green, Amber    
Bo Flow Prepreg /97/98/99/101/126 106 , 1080 /40 Other material on request
Rigid Laminate   0.075 - 1.0mm   Other material on request
Bonded Rigidiser / Stiffener   Coverlay (0.05-0.25mm), FR4 Laminate (0.1-3.2mm), Prepreg Aluminium  
Outline   Breakaway Tab, Single PCB    
Surface Treatment   HASL, HASL lead free (single-side FPC only), ENIG, OSP (no-stiffener only)    
No. Flex Layers   2 8 Higher layer count on request
No Rigid Layers   10 14  
Thickness   0.2 - 3.2mm '0.06-5.00  
Thickness Tolerance (Rigid)   '+/-10% /  
Thickness Tolerance (Flex)   '+/-0.05mm '+/-0.03mm  
Minimum Board Size   '15 x 15 mm '5 x 15 mm  
Max Board Size   '266.7 x 430 mm 350 x 500 mm Larger sizes are avaiable on application
Minimum Track / Gap Inner Layer 17µm 90µm 50µm  
  Inner Layer 35µm 100µm 80µm  
  Inner Layer 70µm 200µm 175µm  
Minimum Track / Gap External Layer 17µm (base) 100µm 75µm  
  External Layer 35µm (base) 125µm 100µm  
  External Layer 70µm (base) 225µm 200µm  
Minimum BGA pad 17um base Copper 250µm 200µm  
10 Layer Rigid Flex

GSPK will discuss your project and manufacture your Flex and Rigid Flex circuits in the materials and surface finishes that precisely meet your application.

Flexible Printed Circuit PCBs
Flex (FPC) PCBs
Flex (FPC) PCBs