Touch Keypad Membrane Switches: Introduction and Usage
Mechanical engineers now use electrical switches to create an open or close electrical current. The current is generated through user controls. The technical advancement has led to a wide variety of switches. However, in recent times, touch keypad membrane switches have become extremely popular.
They have become an important part of any and all electronics that offer machines and human interactions. Since they now are everywhere, therefore, it is important to have a basic understanding of these switches and how to use them.
In this blog post, we will provide you with all the required information. Thus, enlighten you, if you are new in the market. So, without any further delay, let us get started.
Touch Keypad Membrane Switches: All That You Need to Know
When users, press their fingers onto the switch, a switch deformation takes place. This deformation results in the creation of a closed circuit. Once, the user releases a finger, the circuit is open again.
Although it is a simple process, it has the ability to power a number of devices such as smart remote controls, laptops, lamps, and several other smart appliances.
As we did mention above that there is a wide range of switches available, serving different purposes. However, in this case, we would be majorly focusing on the membrane keypad touch switches. The two major categories include the membrane switches and the touch switches.
Both these switches do have the basic same working functionalities; however, they are unique in their own way. The type of switch you use greatly depends upon your equipment and product requirements.
We hardly use a touch switch to power a lamp, however, we might incorporate that in a more sophisticated and smarter appliance such as a microwave. So, here it goes.
Membrane Switch Overview
Although, we have a separate blogpost on a membrane switch, nonetheless, we are going to touch the topic lightly here. Thus, ensuring that you get the gest of what we do the comparison. For more detail, check out our membrane switch article.
Membrane switch is a special type of electrical switch. You will find incorporated in a number of devices. It contains one or more so contacts. Manufacturers use a flexible substrate for the creation of these contacts.
In general, a membrane switch consists of 5 layers. Graphic interface layer on the top then comes the Printed Circuit layer. The logos and the buttons are printed onto the top layer.
The circuit layer is responsible for a number of functionalities. To create this layer, the manufacturer uses conductive material such as the ITO or the PET. Membrane switches are popular due to their flexibility.
Thus, making them the perfect choice for small devices. In addition, you can find a number of backlighting options with membrane switches. For instance, the electroluminescent, the light-emitting diode, or the optical fiber.
Touch Keypad Membrane Switch Overview
The touch switch offers the same functionality as the basic switch as well as all other switches. It means it would create an open and close electrical circuit. Although, it is doing the same thing, but it differs in the way it creates an open and close circuit.
The touch switch supports touch-based control. The membrane touch switches have a momentary action. The reason being, they need the condition of normal to operate. For instance, they normally open, then they push to close and finally they have an immediate opening.
In simpler words, we can say that you would have to press the switch using either a finger or an actuator. Thus, ensuring that the two poles of the switch make contact for it to close the circuit. Once you release the membrane touch switch, the switch returns back to its original condition.
However, before it goes back to its original open positions, the poles are separated.
Manufacturing
To manufacture these touch keypad membrane switches, the manufacturers use a number of techniques. The common is the printing of either carbon or silver ink into a heat-stabilized polyester film.
After then, comes the graphic interface, also the first layer of the switch. The make the graphic layer, you apply an overlay. The reason these top substrates are referred to as the graphic overlay films of membranes is that they are extremely pliable and tin material.
Usage
When it comes to the usage of membrane touch switches, the options are endless. A number of industries use them for a wide range of products and applications. You can find them in aerospace, medical industries.
Moreover, they have extremely popular in consumer markets. They are common among industrial control systems as well. After all, they offer ease of use and effective results. You can even find them in touch-sensitive touch, high-end computer keyboards, and phones.
Their uses are endless. It is not possible to list all of them here. After all, these switches are becoming the norm of the industry especially due to their ability to enhance the aesthetics of the human-machine interface.
They make it convenient for users to interact with machines seamlessly. The advantages are endless.
Membrane Touch Switches: Construction
Now that you are aware of its advantages as well as the application. Let us look at its basic construction.
Note: Although, the interface of every touch screen might be different. However, the basic construction is the same.
The membrane touch switch consists of the following parts.
- User Interface or the Graphic Overlay
- Graphic Adhesive
- The Printed Circuity – Top
- Spacer Adhesive
- Printed Circuitry – Bottom
- Backer adhesive
- Rigid Support Layer
Key Features of Touch Keypad Membrane Switches
For the manufacturing of membrane touch switches, a number of materials come into action. Although the manufacturing process is the same, however, different materials lead to different features of the switch.
For example, if you want the switch to offer durability as well as high-temperature resistant properties, manufacturers recommend using the polyester film for the construction of the switch. Likewise, for all the benefits of polyester material as well as some additional advantages, use the hard-coated polyester film.
After all, these hard-coated films are explicitly designed for the graphics overlay film of the switches. Below, we are the common features that all most all membrane touch switches offer.
- High reliability
- Fast curing
- Strong adhesion
- Carbon Conductors
- Silver Conductors
- Flexibility
- High Conductivity
Types of Membrane Touch Switches
Here are the basic types of membrane touch switches.
Capacitance
First, we have the capacitance touch membrane switch. Similar to the capacitive smartphones, the switches identify the touch via the capacitance body. They are able to open on close the switch via the body. To operate the switch requires just one electrode.
You will find them behind non-conductive panels. For instance, plastic or glass panels.
Resistance
Resistance touch membrane switches feature two electrodes instead of one. For the switch to perform, both these electrodes need to be in contact with any electrically conductive material or a finger. When you touch the switch, it creates an open and closed state.
In comparison to the capacitance switches, resistance switches have a simpler design.
Piezo
Piezo is the least common type of touch keypad membrane switch. The switches incorporate the piezo-ceramic bending properties, and they perform in accord with these properties. They have the ability to work with a wide variety of materials.
Manufacturers build them behind surfaces and panels. The great thing about these switches is they have the capacity to be used as an actuator.
Tactile touch membrane switches
This type of switch reacts once the user makes contact with it. The reason being, the switch comes in contact with the underlying control panel. The user using this switch would feel the snap action of it. They are often seen in laptop keyboards etc.
Non-Tactile Touch Switch
Non-tactile switches, on the other hand, offer durability. They have a stronger build. The reason they offer durability is that they are completely sealed. Thus, there is no dust accumulation.