Flexible PCB must pay attention to the production of matters
Electronic technology is developing rapidly, flexible PCB (printed circuit board) is gradually being widely used in various types of flexibility, and foldability needs of electronic products, to meet the needs of more types of needs, such as wearable devices, folding cell phones, medical equipment, and other fields. Compared with the traditional rigid PCB, and flexible PCB design there are indeed many special requirements, requiring designers from the material, layout, wiring to process, and other aspects of careful consideration, to make the life of the PCB longer.
First of all: the choice of materials is the cornerstone of flexible PCB design, so the choice of materials needs to be careful because flexible PCB needs to have repeated bending, and twisting without damaging the circuit function of the characteristics of the substrate material can not be selected from the traditional rigid PCB materials such as FR-4. Instead polyimide (PI) film such as excellent flexibility, high-temperature resistance, and good insulation properties of the material. The PI film can withstand thousands of times of bending to ensure the reliability of electronic products in daily use. At the same time, the cover layer material also needs special consideration, generally choose to adapt to the substrate with a flexible cover material, to protect the line from external environmental erosion, and in the bending process will not fall off or crack.
Second: the need to fully consider the dynamic use of the product scene, you need to consider the PCB in the bending, and stretching process of the components of the force, weight, not easy to-bend components, etc., as far as possible to put away from the bending area, the rigid area of the flexible PCB or close to the fixed end, to minimize the bending of the components caused by the mechanical stress damage, and reasonable arrangement of components layout, so that the signal direction to comply with the Reasonable arrangement of component layout, so that the signal direction conforms to the bending direction, reduce the perpendicular to the bending direction of the line layout, reduce the risk of line damage.
Third: wiring links, flexible PCB is also different from rigid PCB, avoid laying the alignment in the same direction on each copper layer, it is recommended that staggered alignment, so that the tension between the copper layer is evenly distributed. As flexible PCB bending internal lines will be subjected to varying degrees of stretching and compression, the wiring width can not be too narrow, otherwise it is easy to break in the bending process. Including a reasonable choice of layers, alignment, alignment length, hole design, and the number of adjacent layers of wiring direction, packet ground, signal lines, and so on.
Fourth: Design Rule Check (DRC), wiring design is completed, you need to carefully check the wiring design is consistent with the rules set by the designer, but also need to confirm that the rules set out in line with the needs of the production process of the printed circuit board, flexible PCB manufacturing process is more complex and delicate. Drilling, etching, and other processes require special equipment and parameter control. In the pre-design phase, mechanical simulations were to analyze the stress distribution of PCB in different bending states, and optimize the layout of components; with the help of electromagnetic simulation to check the integrity of the signal, in advance of the discovery and resolution of possible signal interference problems, to avoid in-kind production before the discovery of the problem and rework, and greatly improve the success rate of the design.
Topfast PCB has accumulated rich experience in the field of flexible PCB design and manufacturing for many years. The company is equipped with a professional flexible PCB design team, proficient in the above special requirements and design skills, from accurate selection of suitable materials, to carefully planning the layout and wiring, and then fine control of the manufacturing process, each link is strictly controlled. At the same time, we have international advanced flexible PCB manufacturing equipment, from high-precision CNC drilling machines to precision etching production lines, to ensure that the production of flexible PCB meets the various types of high-end electronic products on the flexibility, reliability of the stringent requirements of the customer to provide high-quality flexible PCB solutions, to help the development of the electronics industry innovation.