Understanding the stack-up structure of flexible PCBs helps engineers select appropriate materials for mechanical durability, signal integrity, and thermal stability. A typical flex PCB consists of four main layers: a base material, copper foil, adhesive, and a coverlay. The base material, often made from polyimide (PI) or polyester (PET), provides flexibility and high-temperature resistance. The diagram on the left illustrates this typical stack-up.
Prototype
No MOQ for prototyping and we have special offer for business clients. Lead time fastest within 24 hours.
Mass Production
Being the long-term strategic supplier of many industry leaders, Asunny is your trustworthy PCB manufacturer. Our monthly capacity is 300,000 m².
Assembly
Our assembly service is available for both small-volume and large-volume production. Our featured service is Flex PCB assembly, with 100k pcs of daily production.
Product description
What is Flexible PCB?
Flexible PCB (Flexible printed circuit board), also known as Flex PCB, FPCB and Flex circuits, is a type of PCB made with flexible base materials like polyimide (PI) or polyester (PET) film. Unlike traditional rigid circuit boards, flexible PCB act as “an electronic dancer,” freely bending, folding, and rolling to adapt seamlessly to complex internal spatial layouts.
Our long-term Partners
End Clients, EMS, OEM & ODM companies we are working with.
Asunny’s goal is to enhance our partners’ supply chain by establishing long-term relationship and striving to be the most reliable PCB supplier. In the past three decades, we have proven our ability to achieve this goal.
Product showcase
Featured Flexible PCB manufactured by Asunny
We manufacture Flex PCB size up to 1.8m*0.5m and up to 8 layers. Our FPCB end clients include Daimler, BYD, Xiaomi, CATL and Desay etc. Our Flex PCB has been applied on various industries such as automotive, new energy, telecommunications, and wearables etc.
1.8m EV Battery Flex PCBA
Layer count: Single-Sided
Application: Battery Cell Monitoring Flex Board for Electric Vehicle (EV) Battery Management System (BMS)
Smart Glasses Flex PCB
Layer count: 4 layers
Application:Main Electronics Interconnect (Display + Sensors + Audio)
EV Battery Flex PCBA
Layer count: Single-sided
Application: Flexible sensing and communication harness for Battery Management System
Automotive headlight Flex PCB
Layer count: Single-Sided
Application: Flexible LED carrier board for adaptive headlights
Smart Glasses Flex PCBA
Layer count: 4 layers
Application: Camera and/or display interface flex PCB
Smartphone Rigid Flex PCB
Layer count: 6 layers
Application: High-speed display interconnect
Automotive headlight Flex PCB
Layer count: Single-sided
Application:LED array board for automotive headlight modules
Smartphone Camera Rigid Flex PCB
Layer count: 8 layers
Application: Camera module interconnect and driver flex board
HDI PCB Manufacturing Capabilities
| Feature | Capability |
|---|---|
| Layer Count | FPC: 2-8 layers, RFPC: 2-10 layers |
| Finished Board Size (Max) | 500mm*1800mm |
| Major CCL Brand | Doosan, Thinflex, Shengyi, Taiyo, DongYi |
| Finished Board Thickness Tolerance | ±10% |
| Minimum mechanical drill | 0.15mm |
| Minimum laser drill | 0.10mm standard, 0.075mm advanced |
| Base Copper Thickness of Outer Layer | 1/3 OZ-1.5 OZ (0.012mm - 0.05mm) |
| Base Copper Thickness of Inner Layer | 1/3 OZ-1.5 OZ (0.012mm - 0.05mm) |
| Board Thickness(withour stiffener) | 0.07mm-2.0mm |
| Aspect Ratio of Plated Hole (Max) | 8:1 |
| Hole Diameter Tolerance (PTH) | ±0.05mm |
| Hole Diameter Tolerance (NPTH) | ±0.05mm |
| Copper Thickness of PTH Wall | 10μm min or meet customer requirement |
| Design Line Width/Space of Inner Layer (Min) | 0.05/0.05mm |
| Design Line Width/Space of Outer Layer (Min) | 0.05/0.05mm |
| Solder Mask Bridge Width (Min) | 0.08mm |
| Solder Mask Alignment Tolerance | ±2mil (±0.05mm) |
| Coverlay Bridge Width (Min) | 8mil (0.2mm) |
| Coverlay Alignment Tolerance | ±6mil (±0.15mm) |
| Dimension Tolerance (Hole to Edge) | ±4mil (±0.1mm) |
| Test Capacity | PAD Size min (0.1mm), PAD Pitch min (0.4mm) |
| Profile method | Laser cutting, Punching |
| Stiffener Type | PI, FR4, Aluminium, Stainless Steel |
| Surface Treatment | HASL, ENIG, ENEPIG, Electrolytic Nickel Gold, Soft gold, Hard gold, Immersion silver and OSP, Immersion tin |
Why Choose Us
Why Choose Asunny For Flex PCB?
We offer full-featured FPCB services. From Design support, prototyping, manufacturing to assembly, all the production are in-house.
30 years of Experience
With our 30 years of industry experience, we have broad project experience with 300+ end clients.
Cutting-Edge Technology
We manufacture Flex PCB size up to 1.8m*0.5m and up to 8 layers. Our FPCB end clients include Daimler, BYD, Xiaomi, CATL and Desay etc.
Tooling made in-house
With our vertical integration, all the FPCB tooling is made by ourselves in Jiujiang Base, saving you both cost and time.
Full-feature Manufacturer
We produce full-range of PCB and offer in-house assembly services. You can get all your projects produced and assembled one-stop.
How it works
PCB Order Process
With our streamlined process, we give any quotation within 24 hours and large batch production in 15 days
1. Submit your RFQ online or through email
Upload or send us your project details including Gerber files, BOM, and other files
2. Quotation and EQs in 24 hours
We will send your our offer and EQs in 24 hours
3. Review and Payment
Review our offer and provide your feedback. After everything is confirmed, you can pay for your order using online payment or direct wire transfer.
4. Quality Check and Delivery
Production will start within 24 hours after payment. Your PCBs and PCBA will go through 100% quality check including AOI, Flying Probe test, E-fixture, Visual Inspection and others. We offer tracked shipping and express shipping (1-3 days air freight).
Explore our wide range of products and services
Our featured products include advanced PCB, Flex PCB, Rigid-Flex PCB and HDI PCB etc. We also provide components procurement service and assembly service.
Multilayer PCB
Manufacturing Price Starts From
$
0.1
Piece Price
- Prototype Lead time 3~7 days
- Manufacturing Lead time 15~20 days
- Layer Count 1~20
- Assembly in-house
- Controlled Impedance PCB
- High-speed materials
*Currently, we accept PayPal, Card Payment and Wire Transfer payment methods.
Flex and Rigid-Flex PCB
Manufacturing Price Starts From
$
0.3
Piece Price
- Prototype Lead time 3~5 days days
- Manufacturing Lead time 15~20 days
- Layer Count 1~10
- Assembly in-house
- Max Dimension 2000mm*550mm
- Sttifeners: PI, FR4, Steel, Tape
*Currently, we accept PayPal, Card Payment and Wire Transfer payment methods.
Advanced/HDI PCB
Manufacturing Price Starts From
$
0.1
Piece Price
- Prototype Lead time: 7~10 days
- Manufacturing Lead time: 15~20 days
- HDI Capability: up to 3+N+3
- Layer Count 1~20
- Assembly in-house
- Via: Blind, Buried, Through-hole
*Currently, we accept PayPal, Card Payment and Wire Transfer payment methods.
Need support?
CONTACT YOUR DEDICATED MANAGER FOR SUPPORT
Rebecca Lu
International sales manager
Based in Oxford, Rebecca has 2 years of experience in Amazon UK and 3 years of PCB industrial experience. She is fluent in both English and Mandarin.
Xi Yang
Senior Sales Manager
Xi has been working in Asunny since 2002. She has rich project experience and deep understanding of the industry. Reach out for Mandarin service.
Lynn Zhu
Sales Assistant
Lynn has 2 years of industry experience. She studied and worked in Korea for the past 8 years. She is fluent in Korean and Mandarin.
Chao Jun Pu
Engineering Lead
Chao Jun has been in the industry for over 8 years and he worked in a few listed companies. He has rich product and project experience.
Common Questions
Most Popular Questions.
If you have any other questions, please contact us for support
Yes, Flexible PCB can withstand high or extreme temperatures (including extremely low temperatures), making it suitable for automotive, aerospace, and industrial applications. Most flexible PCBs use polyimide (PI) or a similar polymer as the base material. Polyimide is known for its excellent thermal resistance, withstanding temperatures up to 260°C or more.
Yes, Flexible PCB can be fully customised in terms of size, length, shape, layer count, and materials to meet any specific requirements.
We can do either laser cutting and Punching. All the tooling is made by ourselves which saves cost for your FPCB projects. You will be able to keep your customised tooling as your asset.
For single sided Flexible PCB, the fastest build time will be 24 hours and for double sided, it will be fastest 48 hours. For multilayer, it will depend on the specific design. Please notice that priority service fee will be charged based on your demanded quantity and provided board design.
We can refund your prototyping fee if you proceed to mass production with us. Please get in touch with us to learn more about what we offer to our long-term business partners.
We hold all the essential quality management certificates such as ISO9001. Please check out our certifications at about us section. All our Flexible PCBs are tested under IPC-TM-650 standards. If there are any issues with your orders, you can always get in touch with you assigned account manager for a product exchange or return.
Lets get your PCB project started!
We are the full-feature PCB & FPCB manufacturer and Assembly services provider
Need Help?
Don’t hesitate to contact us for more information about company or service
Headquarter Address：Gangxing Road 128, Jiujiang City, Jiang Xi province, China
Sales Centre: Nanshan CTF centre Room 2603, Shenzhen; 81 St.Clement's Angel Court, Oxford
Sales Centre: Nanshan CTF centre Room 2603, Shenzhen; 81 St.Clement's Angel Court, Oxford
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