Flexible circuit board is a special type of printed circuit board. Its characteristics are light weight, thin thickness, softness, and flexibility.
Mainly used in many products such as mobile phones, laptops, PDAs, digital cameras, LCD displays, etc.
The demand for flexible PCBs in various industries is increasing, with particularly strong demand in the medical, military, and industrial markets.
| Classification | project | production capacity | |
| Inspection standards | Acceptance Criteria | Civilian products, Class 2 products | IPC-A-600 IPC-6013 GJB7548 |
| Military products, grade 3 products | |||
| experiment method | IPC-TM-650 GB/T4677-2002 | ||
| file processing | Handle file formats | Tango/Pads2002 | |
| Protel series | |||
| Powerpcb/Genesis | |||
| dxf/dwg | |||
| Gerber file format | Photopainting file (Gerber file) and corresponding drilling file | ||
| | Flexible substrate (adhesive-free, rolled copper) | Xinyang, Shengyi | PI thickness 1/2/3/4mil, copper thickness 1/2, 1Oz |
| Panasonic RF775/RF777 | PI thickness 1/2/3/4mil, copper thickness 1/2, 1Oz | ||
| Dupont AP | PI thickness 1/2/3/4mil, copper thickness 1/2, 1Oz | ||
| | CVL | Epoxy adhesive system (pine poplar) | PI thickness 0.5, 1mil, glue thickness 1mil |
| Acrylic adhesive system (DuPont) | PI thickness 1mil, glue thickness 1mil | ||
| | Prepreg | Shengyi SP168GL | 1067, 1078 |
| Tenghui VT447 | 1067, 1078 | ||
| | Outer copper foil | 18, 35, 70um | |
| | PI reinforcement | Acrylic glue | PI thickness 4/8mil, glue thickness 1mil |
| | Pure rubber | Epoxy glue system/acrylic glue system | 40um thick |
| | Shielding film | SF-PC6000 | |
| Dimensions | layer | 1-8 floors | |
| Finished board size (maximum) | Single side (not press CVL) | The shortest side is up to 480mm, and the long side is not limited | |
| Single side (need to press CVL) | The shortest side is up to 230mm, and the long side is not limited | ||
| Double-sided (need to press CVL) | 470*580mm | ||
| Multi-layer soft board (3-8 layers) | Short side size 220mm, long side unlimited | ||
| Thickness of single-sided soft board (without PI reinforcement) | No pressure CVL | 0.04-0.08mm (sheet size 25-50um, copper thickness 18/35um) | |
| Laminated CVL | Conventional 0.08-0.13mm (substrate sheet specification 25/50um, copper thickness 18/35um, CVL specification 12.5/25-25/25) | ||
| Maximum thickness 0.18mm (substrate specification 75/100um) | |||
| Double-sided flexible board thickness (without PI reinforcement) | Laminated CVL | Conventional 0.115-0.21mm (substrate sheet specification 25/50um, copper thickness 18/35um, CVL specification 12.5/25-25/25) | |
| Maximum thickness 0.27mm (substrate specification 75/100um) | |||
| Multilayer board thickness | 0.3-4.0mm | ||
| Plate Thickness Tolerance | ≤0.5mm | ±0.05mm | |
| 0.5-1.0mm | ±0.1mm | ||
| 1.0-4.0mm | ±10% | ||
| inner graphics | Minimum Line Width/Space | Base copper 18um | 3.5/3.5mil |
| Base copper 35um | 5/4mil | ||
| Base copper 70um (hard board) | 8/5mil | ||
| Inner minimum pad | 0.125mm (18/35um base copper), 0.15mm (70um base copper) | ||
| electrical ground isolation | 0.25mm | ||
| | Drilling aperture range | 0.2-6.3mm (interval 0.05mm) | |
| drilling | Minimum distance from drill hole to conductor | ≤6 layers | 8mil |
| ≤16 layers | 10mil | ||
| electrical ground isolation | same network | 6mil | |
| different network | 12mil | ||
| Minimum NPTH hole | 0.5mm | ||
| Aperture Tolerance | ±0.05mm | ||
| Immersion Copper Plating | Hole Plating Aspect Ratio | 10:1 | |
| Aperture | Minimum 0.2mm | ||
| outer graphics | Minimum Line Width/Space | H/H+plating | 4/3.5mil |
| 1/1+plating | 5/3.5mil | ||
| 2/2+plating | 9/5mil | ||
| Distance from conductive pattern to outer edge | Minimum 8mil | ||
| Grid Line Width/Spacing | H/H+plating | 6/6mil | |
| 1/1+plating | 6/6mil | ||
| 2/2+plating | 10/8mil | ||
| Solder mask | Solder mask bridge width (minimum) | green oil | 4mil |
| Other variegated ink | 5mil | ||
| Solder mask color | Green, blue, yellow, red, white, black | ||
| Minimum window size on one side of solder mask | 2.5mil | ||
| Minimum unilateral width of solder mask line | 2.5mil (partial 2mil) | ||
| characters | character color | white, yellow, black, gray | |
| Pad to character minimum pitch | 6mil | ||
| Character Line Width/Character Height | Base copper 18um | Character width/character height: 4mil/27mil | |
| Base copper 35um | Character width/character height: 5mil/30mil | ||
| Base copper 70um | Character width/character height: 6mil/45mil | ||
| surface treatment | lead HASL | Tin thickness 2-40um | |
| Electroplated gold fingers | Nickel thickness is 3-5um, gold thickness is 0.125-0.254um, the maximum finger length is 2inch, and the minimum finger spacing is 7mil | ||
| OSP | Film thickness 0.15-0.3um | ||
| Lead-free HASL | Tin thickness 2-40um | ||
| Shen tin | Tin thickness 0.8-1.2um | ||
| sinking silver | Silver thickness 0.1-0.3um | ||
| sinking gold | Nickel thickness: 3-5um, gold thickness: 0.03-0.1um | ||
| molding | Milling Profile Tolerance (Edge to Edge) | ±0.15mms | |
| Minimal arc of milling shape (inner angle) | 0.4mm | ||
| Milling slot minimum tolerance | ±0.15mm | ||
| VCUT | VCUT angle | 20°, 30°, 45°, 60° | |
| VCUT angle tolerance | ±5°s | ||
| VCUT excess thickness tolerance | ±0.1mm | ||
| Impedance | control method | single-ended/differential | |
| control tolerance | ≤50Ω | ±5Ω | |
| >50Ω | ±10% | ||
| finished product | plate song | ≤0.7% | |
| Packing | vacuum paper | ||
