The Pros and Cons of Various Common Types of Membrane Switches
The membrane switch is an operating system that integrates key functions, indicating elements, and instrument panels. It consists of four parts: panel, upper circuit, isolation layer, and lower circuit. When the membrane switch is pressed, the contact of the upper circuit deforms downward and contacts the plate of the lower circuit. When the finger is released, the contact of the upper circuit rebounds, the circuit is disconnected, and the loop triggers a signal.
Membrane switches have a rigorous structure, beautiful appearance, good sealing, moisture resistance, and long service life. Membrane switches have different structures and processes for different user groups, environments, and terminal devices. Singway will talk to you about the advantages and disadvantages of several common types of membrane switches.
Advantages and disadvantages of several common types of membrane switches
1. Metal dome (pot) type: metal dome is used as the conducting medium.
Advantages: good key feel, uniform force, high stroke accuracy; crisp sound can be heard during operation, and the operation status can be clearly known, avoiding repeated operations due to buffer time of some equipment; the operating temperature can reach -20 ~ 80℃
Disadvantages: When the lining is uneven or pasted on a large bending arc, the spring may cause short circuit, malfunction and non-rebound.
Suggestion: Use on a flat lining that can withstand the force of the key, or directly use a thickened PCB as the circuit layer.
2. Hot-pressed convex feel type: After printing the contact surface with film material, the convex points are rolled to form a rebound force.
Advantages: long service life, which can reach more than 500,000 times; good feel, and the stroke and force can be customized according to customer needs.
Disadvantages: The mold cost is high, and a convex mold needs to be opened; using it in a high temperature environment may cause the key force to weaken.
Suggestion: The convex mold should be opened with a hardware mold to ensure the consistency of the key force and stroke.
3. Flat touch type: The contact point uses a thin film substrate to print the conductor, and no secondary process is used.
Advantages: The key life is long, up to one million times; the conductive contact area is large to ensure the conductivity.
Disadvantages: No operating feel, easy to cause repeated operation or misoperation;
Suggestion: The key spacing should be enlarged as much as possible, otherwise it will increase the failure rate and reduce the life.
4. Capacitive induction type: Use conductive body to sense conduction.
Advantages: Like capacitive touch screen, it can sense movement within a certain distance; the sensing distance can be designed according to customer specifications.
Disadvantages: The qualified rate of finished products is low, it is more sensitive to surrounding electromagnetic interference, and the design requirements are very high; it requires related electronic components and chip support.
5. PCB circuit type: Use PCB circuit board to replace the thin film circuit layer
Advantages: PCB circuit has high precision, LED welding is more solid and reliable, and the resistance value is lower; the thickened PCB circuit layer can be used directly as a lining board.
Disadvantages: PCB is a hard material and cannot be bent.
Membrane switches have a wide range of applications and are widely used in electronic communications, electronic measuring instruments, industrial control, medical equipment, automotive industry, smart toys, household appliances and other fields. Here are the introductions to several common types of membrane switches. If you want to know more about membrane switches, you can pay attention to Singway, a membrane switch panel manufacturer that focuses on membrane switches, membrane panel processing, and membrane button customization. It provides industrial control membrane switch customization, touch panel processing, membrane button panel, and industrial control membrane switch research and development. For details, you can log in to the official website to consult customer service (https://singway-touch.com/)!