Keypads are used extensively in human machine interfaces (HMIs), mechanical control system and electronic devices. In recent years, however, many manufacturers have began using silicone rubber keypads instead of traditional plastic keypads. Today, we’re going to explore the growing trend of silicone rubber keypads, revealing how they work and why they’ve become a popular alternative to plastic keypads.
Silicone Rubber Keypads: The Basics
Also known as elastomeric keypads, silicone rubber keypads are keypads made of silicone rubber webbing. As you may know, silicone rubber is a soft and flexible material — more so than plastic. When used in the construction of a keypad, it offers several unique properties. The soft properties of silicone rubber, for example, create natural tactile feedback when pressed. As you press your finger against a key, the silicone rubber webbing will deform. And when you release your finger, the webbing will “bounce back” to its original shape, thereby creating light but noticeable tactile feedback.
How Silicone Rubber Keypads Work
Silicone rubber keypads are designed in different ways, but most follow a similar construction consisting of silicone rubber webbing around a switch. Underneath the silicone rubber webbing is a conductive contact, and below this contact is another conductive contact.
When you press the button, the webbing deforms, at which point the two conductive contacts meet. This completes the circuit, telling the connected device that you pressed the switch. There are different ways to design silicone rubber keypads, but they all involve the use of silicone rubber material for the webbing, which is usually found above and around an electrical switch.
Advantages of Using Silicone Rubber Keypads
Silicone rubber keypads offer several advantages over keypads made of plastic and other traditional materials. For starters, they are resistant to moisture and liquids. Once the silicone rubber webbing is placed over the switch, it creates a waterproof barrier, allowing the keypad to be used in outdoor environments or other applications where moisture is common.
In addition to being moisture- and liquid-resistant, silicone rubber keypads also support backlighting. The most common types of backlights used in silicone rubber keypads include electroluminescent (EL) and light-emitting diode (LED). Both are highly efficient and effective ways to illuminate the keypad’s legends when used in conjunction with laser etching.
Silicone rubber keypads are also comfortable to use. Since they are made of silicone rubber webbing, they have a naturally soft and flexible texture that’s easy on your fingers.