Solution to the elastic loss of FPC thin film key switch?

Solution to the elastic loss of FPC thin film key switch

FPC Thin Film Key Switch Solution

The FPC thin film key switch is a system that combines keys, indicators, and instrument panel functions into one. It consists of a panel, upper circuit, isolation layer, and lower circuit. When pressure is applied to the film switch, the upper circuit contacts deform downward, allowing the lower circuit board to conduct. When the pressure is released, the upper circuit contacts rebound, opening the circuit and sending a trigger signal.

One potential issue with film keys is that the 1.00 mm outlet distance of the Silver Paste circuit is simple, making it prone to conductor puncture. Additionally, if the keys do not rebound and lose elasticity completely, it can lead to malfunction.

There are two types of touch sensitive membrane switches: those cartridges and those blister circuits. The key elastic loss is the deformation and elastic loss of the key internal elastic fragments or bubbles. In the process of packaging, transportation and storage, the elastic membrane switch is subjected to great pressure, which easily leads to the deformation of the shrapnel and the weakening of the handle, and finally loses its elasticity completely and deforms during the Second Assembly. Similarly, if the user did not paste the first time during the installation process, the second time the paste tear, the shrapnel will also be deformed. Therefore, the FPC film key switch in the production and installation process need to do a good job with shrapnel. On the circuit of the bubble film switch (some are directly outside the board surface of the bubble) , each link also to prevent heavy pressure to prevent bubble deformation. It also prevents use at high temperatures, where the heat expands and contracts, and the button is simple and soft, after all, the spring is completely inoperative. Consistency of key forces is also important for circuit drums. The surface glue on the circuit and the air vent of the interlayer can make the consistency strength of the key better, and also can avoid the key not to rebound.

Classification As its applications

When the button is embossed, there are three basic options: pillow embosses, rim  embosses and thin translucent emboss , Additionally and custom  are available.

The following as three kinds of different emboss membrane graphic overlays from its applications and functions. Something like this, romote controller in our daily life, composed of the graphic overlay is made of silicon rubber, on which of surface, you can find its keys can be embossed to different shapes according to its application. It looks having a different views, also the silicon rubber can enhance soft tactile feeling. Therefore on the positive face, spread some pillow keys evenly.

Different Applications for differnet classification

When tactile feedback is necessary, the pillow emboss enables the membrane switch to have a thinner construction. The pillow will be placed on top of the metal dome and offer satisfying tactile feedback.

The buttons use the rim emboss (with or without tactile feedback). With this design, the user can use a finger to find the key.

Utilizing a membrane design with LEDs built into the circuit board. This is a practical approach to creating the switch backlit effective. As soon as the switch is connected by electricity, it looks is so clear. Like this, it can be operated in convenient in dark environment.