Skip to main content
Flexible Printed Circuit Assembly with a PCB

Printed Electronics

Flexible Printed Circuits (FPCs)

Flexible printed circuits (FPCs) combine the routing and component assembly of PCBs with the flexibility of cable assemblies, helping designers meet the most challenging space, weight and performance requirements. Molex FPCs enhance design flexibility, high-speed signal integrity and reliability. Customizable layouts, exceptional impedance control, and superior resistance to heat and vibration make FPCs ideal for compact and dynamic applications in a wide range of industries.

Contact Us

Features and Benefits

Engineers designing miniaturized electronic devices must ensure reliable performance within a compact form factor. Achieving high-speed communication requires precise signal integrity, while robust mechanical and thermal qualities are essential for dependable operation in environments prone to vibration and temperature extremes. Additionally, interconnects must be optimized for easy assembly in tight spaces to support efficient and effective designs.

FPCs deliver the performance and flexibility to address these challenges. Integrated shielding improves impedance control and reduces signal loss, enabling high data rates. Enhanced thermal properties support reliable operation in challenging applications subject to extreme temperatures. Lightweight, durable and flexible materials enhance design flexibility by providing a smaller bend radius and help ensure reliable operation in space-constrained applications or devices subject to shock and vibration.

Molex FPCs use impedance control and shielding to optimize signal integrity, enabling high-speed and high-performance applications. Exceptional flexibility permits bending and flexing to meet complex circuit requirements and simplify assembly without sacrificing product longevity or reliability. Enhanced thermal capabilities withstand extreme conditions, including temperatures as high as +130°C, supporting use with a variety of applications.

Flexible Printed Circuit (FPC) Interconnect Assemblies

Customizable high-performance FPC interconnect assemblies allow designers to attach board-mountable connectors and other electrical components directly to the FPC, providing an integrated, one-piece solution to complex electronic packaging challenges. These assemblies simplify designs, reduce the bill of materials (BOM) and accelerate assembly processes. Single-sided, double-sided and multi-layer flex circuit options are available to meet specific requirements.

FPC Interconnect Assembly

Multi-Layer Assemblies

Ideal for high-density routing, multi-layer assemblies provide three or more layers of flexible circuitry to optimize space and performance. Numerous interconnect options are available, paired with a flexible circuit design that ensures superior impedance control and minimizes signal loss.

FPC Multi-Layer Assembly

Rigid Flex Circuits and Assemblies

Rigid flex circuits and assemblies combine the diverse capabilities of PCBs with the flexibility of FPCs. The assemblies help reduce the number of connectors and cables, improving reliability, while press-fit connector and dual-side surface-mount technology (SMT) capabilities enhance design flexibility.

Enhances signal integrity 
The material used in the construction of FPCs minimizes signal loss, enabling exceptional high-speed signal performance. 

Provides superior impedance control
The FPC conductor and shielding are manufactured to precision tolerances that ensure consistent impedance to avoid signal degradation, data loss and electromagnetic interference for high-performance devices. 

Enables use in extreme temperatures 
FPCs use materials with closely matching thermal expansion rates, improving reliability in hot and cold environments and applications subject to large temperature fluctuations. This minimizes the thermal stress effects of temperature cycling, such as cracking and warping of FPCs. 

Simplifies thermal management 
The advanced materials and thin design of FPCs reduce the need for dual-sided cooling and help dissipate heat rapidly, helping prevent heat buildup. 

Reduces space requirements 
FPCs are designed to occupy three dimensions and can be folded over themselves or around packaging to fit into small spaces within miniaturized devices. 

Minimizes weight 
FPCs are significantly thinner and lighter than traditional circuit boards, reducing weight in miniaturized devices. 

Applications by Industry

ADAS
Automotive miniaturization
Center stack system
Charging infrastructure
Electric vehicles
EV battery assemblies 
In-cabin applications
Lighting control modules
Steering wheel 

This is not a definitive list of applications for this product. It represents some of the more common uses.

Frequently Asked Questions

What are flexible printed circuits (FPCs)?

Flexible printed circuits (FPCs) are similar to PCBs, integrating conductive traces and electronic components, but use a flexible substrate to enable bending or folding. They combine the routing and component assembly capabilities of PCBs with the flexibility of cable assemblies. They support 3D packaging and can be folded or creased to fit into compact areas, enabling device miniaturization. 

How can designers without experience in flex circuitry best utilize the advantages of FPCs?

Designers with minimal to no experience in flex circuitry architecture can still harness the benefits of FPCs by collaborating with experts and leveraging available design tools and resources. Molex has over 45 years of experience working with customers to design, develop and manufacture FPCs. Molex engineers work with designers every step of the way to ensure FPC designs are optimized for the specific application.

How does the cost of an FPC compare with alternatives?

For miniaturized applications in tight spaces, FPCs and FPC assemblies often cost less than traditional PCB alternatives by providing an all-in-one solution that integrates multiple functions into one assembly. They can help reduce costs by simplifying the BOM, accelerating assembly operations and reducing the number of potential failure points. The Molex team works with designers to find the optimal FPC solutions for specific applications.

Can FPCs withstand harsh environments without the copper traces cracking or breaking?

Yes, modern FPCs are designed with robust, temperature resistant materials, providing exceptional resilience in applications subject to shock, vibration and large temperature fluctuations. They are far more durable and reliable than earlier generations of FPCs, which relied extensively on PCB designs and materials. Molex FPCs are an ideal solution for demanding applications.