Thin-film switches classified by structure

Release date:

2024-12-23

1) Flat, non-sensory type:

Long service life, yet lacks tactile feedback.

2) Film-type with raised convex tactile surface:

It offers a pleasant tactile feel, but its service life is relatively short.

3) Convex border-style, tactile-free type:

It has an aesthetically pleasing appearance with a strong sense of depth, yet it lacks tactile feedback.

4) Convex border-type tactile:

Visually appealing, with a strong sense of depth and tactile texture.

5) Panel-embossed tactile type

(a) Type: When designed improperly, it is prone to exhibit a two-segment phenomenon; however, the panel may also suffer damage, and electrical performance could still be compromised.

Type (b): There is no two-segment phenomenon, and the structural layer is minimal, making it more economical. However, if the panel is damaged, the electrical performance will be compromised entirely.

6) Metal Fragment Type:

(a) Type: A basic and commonly used structure. The fragment serves both as a tactile element and as an upper circuit component;

(b) Type: Features a complex structure, designed for applications requiring a high density of shrapnel without the need for jumper wires. The shrapnel is placed on the upper circuit path, with both the upper and lower conductive surfaces facing upward. The upper circuit path requires punching holes. In this structural configuration, when conducting, the four legs of the shrapnel do not lie in the same plane as the central point, resulting in a "two-stage" behavior. Additionally, the shrapnel often remains in an excessively concave state over time. Prolonged exposure to this condition can lead to the shrapnel losing its ability to rebound. Therefore, this design is not recommended for use.

(C) Type: The fragment is placed on the upper track, serving only as a tactile element. Its upper conductive surface faces downward, while the lower conductive surface faces upward. This "two-segment" configuration is not recommended for use.

(d) Type: The shrapnel is placed on the lower circuit, with traces running both above and below. It serves dual functions—providing tactile feedback while simultaneously connecting the upper and lower circuits. This design is suitable for applications requiring a high density of shrapnel without the need for jumper wires, offering a simpler structure compared to (b). During design, ensure that the circuit traces avoid the four legs of the shrapnel to prevent short circuits.

7) Luminous Body Type: Be sure to apply the base gel mold.

(a) LED wiring on the same layer as the underlying circuitry: This design is simple, but if the selected LED height is relatively high, the LED may lift the panel upward. In such cases, the LED window on the panel should be designed with a raised feature, or the thickness of the surface adhesive layer should be increased to ensure it exceeds the LED's height.

(b) LED routing on a different layer from the underlying circuitry: Although the structure is more complex, the LED window does not necessarily need to be raised. However, the area directly above the LED must be hollowed out to ensure that light can pass through the LED aperture. Note that during routing of the underlying circuitry, care must be taken to avoid running traces around the perimeter of the LED aperture.

8) Foldable type:

This type can largely avoid jumper wires and eliminates the need for hole-punching, allowing the conductive surface to face downward. However, a drawback of this structure is that the wiring tends to break easily at the folding point.

9) Waterproof Type with Inner and Outer Frames

The outer frame is a closed enclosure without any wiring, providing protection to the inner frame and preventing moisture from entering the housing through the cable outlet groove.

Steps for Using a Membrane Switch

The service life of the membrane switch varies depending on different environmental conditions.