I. Specifications
| Item | Specification |
|---|---|
| Product Name | Polyimide FPC Board, Multi-Unit Flex Cable for Modules |
| Base Material | Polyimide (PI), adhesive / adhesiveless PI film optional |
| Layer Count | 1 / 2 layers (mainstream), 4 layers flex available |
| PI Film Thickness | 12.5μm, 25μm, 50μm, 75μm, 125μm |
| Copper Foil | RA Rolled Annealed Copper (12μm / 18μm / 35μm), ED copper for static application |
| Coverlay | PI coverlay, yellow / black / white coverlay optional |
| Surface Finish | ENIG, ENEPIG, OSP, Immersion Silver, Gold finger plating |
| Min Trace / Space | 0.075mm / 0.075mm |
| Min Bend Radius | 0.5mm (dynamic bending), 0.3mm (static bend) |
| Operating Temperature | -40℃ ~ +180℃ |
| Dielectric Constant Dk | 3.2–3.5 @1GHz |
| Flex Cycle Life | ≥100,000 dynamic bending cycles (RA copper design) |
| Stiffener | FR4 / PI / PET stiffener for connector soldering area |
| Outline Tolerance | ±0.05mm |
| Compliance | IPC-6013, RoHS, REACH, UL94 V-0 |
| Structure Feature | Multi-unit array layout, easy singulation after SMT |
II. Features
- Made of high-performance polyimide substrate, outstanding heat resistance, can withstand lead-free reflow soldering up to 260℃ without delamination or bubbling.
- Multi-unit array design, multiple flex cables connected in one panel, suitable for batch SMT assembly and easy separation for module mass production.
- Lightweight, ultra-thin and flexible, supports folding, bending and 3D routing inside compact modules, replacing discrete wire harnesses.
- RA annealed copper conductor, excellent anti-fatigue performance for repeated bending movement.
- Custom pin count, length, width and gold fingers according to module interface requirements.
- Optional stiffener on the connector end to improve soldering stability and avoid pad lifting.
- Stable insulation performance, low signal crosstalk for sensor, display and camera module interconnection.
- Good chemical resistance, resist flux, cleaning solvent and moisture in normal working environment.
III. Design Principle
This multi-unit FPC flex cable adopts polyimide flexible circuit structure for module interconnection:
- PI substrate core: Polyimide film acts as flexible dielectric layer, providing insulation, flexibility and high-temperature resistance.
- Multi-unit array layout: Several independent flex cable units are arranged on the same panel, connected by tiny break tabs. After component soldering, customers can separate each flex cable manually or by jig. This greatly improves SMT efficiency for module production line.
- Conductor design: Rolled annealed copper is used for bend zone; copper trace direction is arranged perpendicular to bending axis to reduce copper fracture risk.
- Coverlay protection: PI coverlay laminates on circuit surface to protect copper traces from oxidation, scratch and short circuit.
- Stiffener zone: Stiffener is pasted at connector/gold finger area to keep flat during soldering and connector plugging.
Difference from ordinary single FPC: Focus on mass module production, array panel is the core design point.
IV. Core Manufacturing Advantages
- Adhesive-less PI process available, lower thermal expansion, better bending life and less outgassing.
- Precision exposure and etching process, stable fine line capability for narrow pitch module FPC.
- Controlled lamination pressure & temperature, reduce residual stress to avoid warpage after singulation.
- Professional multi-unit panel layout service, optimize break tab design for clean separation without circuit damage.
- Precision gold finger plating, uniform gold thickness, stable plugging performance for module connectors.
- 100% open-short electrical test + AOI inspection before shipment.
- Support prototype quick turnaround and mass batch production, flexible MOQ for module OEM customers.
V. Signal & Electrical Performance
- Insulation resistance: ≥10¹² Ω between adjacent traces, low leakage current.
- Impedance control: Can realize single-ended / differential impedance design for high-speed module signals such as MIPI, LVDS.
- Current carrying: 18μm copper ~1A, 35μm copper ~2–3A, suitable for low-voltage power and signal transmission inside modules.
- Bandwidth: Works well for DC, analog sensor signals, high-speed differential module signals; not suitable for ultra-high power continuous load.
- Crosstalk: Proper ground shielding design can reduce crosstalk for parallel multi-channel module signals.
- Stability: PI material maintains stable electrical performance under temperature cycling and vibration environment inside compact modules.
We are a professional PCB & FPC manufacturer located in Shenzhen, China. We focus on custom rigid PCB, HDI board, FPC flexible circuit, rigid-flex PCB and metal core PCB for global customers.
With strict IPC quality standards, we provide one-stop service from prototype, small batch to mass production. Our products serve industrial control, sensors, display modules, automotive, medical and consumer electronics markets.
We support fast sampling, competitive pricing and reliable after-sales service for PCB buyers from Europe, Russia and other regions.
