What is the working principle of the membrane switch panel?

2020-11-16

　

Working principle of membrane switch panel

The membrane switch panel is an operating system that integrates key functions, indicator elements, and instrument panels. It is composed of five parts: graphic overlay panel, upper circuit, isolation layer, lower circuit and backside adhesive. When the membrane switch is pressed, the contact of the upper circuit deforms downwards, and the conductive gold finger of the lower circuit is contacted and conducted. When the finger is released, the upper circuit contact bounces back, the circuit is disconnected, and the circuit triggers a signal.

Working principle of membrane switch panel

The main structure of the membrane switch panel is generally composed of a membrane button panel and a membrane circuit. The thickness of the membrane switch pattern overlay is generally controlled at about 0.15-0.2mm. If the button is too thin, there will be no resilience. The use of the switch is also It is not so sensitive. If it is too thick, pressing the button will be very laborious, which is not good for the entire product.

When making a flat switch, when choosing a film, it tends to choose a slightly higher thickness to ensure the long-term use of the product. Another type of panel used in circuit contacts requires a slightly thinner panel. Only when the diameter of the embossing is compared, a thinner film panel will be used.

The overall structure design of the membrane keypad is very simple. When the original sample membrane switch panel is obtained, if you want to observe the principle of the circuit board of the panel, you only need to remove the button panel to see the membrane switch circuit.

When the shape of the designed film button is relatively large, it is best to choose a film with a thickness of 0.18-0.2 mm. This film thickness is moderate, has a good rebound effect, can be pressed frequently, has a long life, and is not easy to damage. If the selected film thickness is not enough, it is easy to penetrate. Make the membrane switch insensitive.

The membrane switch panel has many advantages. Compared with other different types of buttons, its working principle is outstanding. It welds many conductive metal points on a conductive film. Each button can be connected to the same membrane switch. The buttons of the film panel correspond to the working circuits, which can achieve different control effects. The film panel has a barrier layer. Its function is that the entire button and the panel do not react when the button is not used, and the circuit is turned on when pressed.Instructions to complete circuit functions.