FPC Membrane Keypad with Silicone

FPC thin film switch is made by changing the traditional PET circuit thin film switch to FPC circuit. Traditional PET circuit USES screen printing technology to print conductive silver paste on PET substrate to form electrical carrier with conductive function. The base material of FPC is mainly polyimide copper clad plate, which is made by etching or laser engraving technology. With better electrical performance, temperature resistance, waterproof and oxidation resistance, more precise and precise lines can be laid out in the limited space to save the corresponding space to achieve more ideal design effect, line width and line distance can reach 8~10 times of the silver paste circuit. Meanwhile, due to the excellent characteristics of FPC, there are more options for surface mount components to achieve the corresponding control effect.

Silicone membrane switch is on the surface of the membrane switch using silicone button products, so that the switch has a stronger sense of touch and relatively better feel. However, due to the uneven surface of silica gel, it is difficult to design, mark and other aspects. Therefore, it is often necessary to laminate the membrane panel on the surface of silica gel to make the whole switch look more exquisite.

Species

1. The single panel is made of single-side PI copper-coated material after the completion of the circuit, and then covered with a protective film, forming a kind of soft circuit board with only one layer of conductor.

2. Common double panels are copper coated with double-sided PI board. After the completion of the double-sided circuit, a protective film is added on both sides to make a circuit board with double conductors.

3. The substrate generates a single panel using pure copper foil in the circuit manufacturing process, and adds a protective film on each side successively to become a circuit board with only a single layer of conductor but with conductors exposed on both sides of the circuit board.

4. The base plate generates double panels, which are laminated with two layers of single-sided PI copper clad plate materials and supplemented by window binder at specific positions, to become a double-sided conductor circuit board with local area lamination and two-layer separation structure in order to achieve a circuit board with high flexural performance in the layered area

The advantages and disadvantages

1. Advantages :(1) can be freely bent, wound and folded, can be arranged arbitrarily according to the spatial layout requirements, and can be moved and expanded arbitrarily in the three-dimensional space, so as to achieve the integration of component assembly and wire connection;(2) the use of FPC can greatly reduce the size and weight of electronic products, suitable for electronic products to high density, miniaturization, high reliable direction of development needs.Therefore, FPC flexible board has been widely used in aerospace, military, mobile communication, laptop, computer peripherals, PDA, digital cameras and other fields or products.(3) FPC flexible board also has the advantages of good heat dissipation and weldability, easy installation and connection, low comprehensive cost, etc., and the design of soft and hard combination also makes up for the slight deficiency of flexible substrate in the bearing capacity of components to a certain extent.

2. Disadvantages :(1) high one-time initial cost. Since soft PCB is designed and manufactured for special applications, the initial circuit design, wiring and photographic plate costs are relatively high.Generally, it is best not to use a soft PCB unless there is a special need to apply it.(2) it is difficult to change and repair the soft PCB. Once the soft PCB is made, the change must start from the base drawing or the light drawing program, so it is not easy to change.Its surface is covered with a protective film, which should be removed before repair, and then restored after repair, which is a difficult work.(3) limited size in the case of soft PCB is not popular, usually by batch process manufacturing, so limited by the size of production equipment, can not be very long, very wide.(4) improper operation is easy to damage, improper operation of installation personnel is easy to cause damage to the soft circuit, its tin welding and rework need trained personnel to operate.