FPC is a flexible board, and there are many device packages on the PCB that can only be used for rigid boards (hard material PCBs, such as FR-4 or PTFE).

If flexible plates must be used, then you must consider using a material that combines rigid and flexible materials.

The specific method is to make QFP and SOIC packaged devices on a rigid board, and the resistive and capacitive devices are also made on the rigid board. (Because the flexible board has high degrees of freedom in bending, the devices cannot be directly welded on it. The devices are hard, while the FPC substrate is soft, and the solder pads will fall off.) The flexible board part is actually the function of ribbon wiring. When welding, it is necessary to find a SMT machine with vacuum adsorption equipment or create a fixture. Whether soldering is lead-free or with lead, and whether wave soldering is required, it should be clearly explained to the PCB manufacturing supplier, as the temperature resistance effect needs to be considered when selecting materials. Based on the first production of flexible plates, it is necessary to understand whether the current supplier has the qualifications to produce FPC, and whether there are equipment and execution standards for FPC bending testing, so as not to be fooled.

Lastly, based on installation considerations, I still want to try new processes. The overall strength and lifespan of flexible boards are far inferior to those of rigid boards.