Automotive Rubber Keyboard Design Guide | Custom Silicone Auto Industry Keypad

Auto Conductive Rubber Keypad, also referred to as Automobile Silicone Buttons, Automotive Silicone Rubber Switch. Custom Silicone Auto Keypad used in car content, is made of SHIN-ETSU silicone rubber with excellent resilience. Auto Rubber Button Pad has three main conductive methods: golden pill, nickel pill & low-resistance carbon pill. We can customize various Automotive Elastomer Keypad such as car centre panel silicone keypad, steering wheel-mounted controls silicone keyboard, car navigation buttons, car window control silicone keypad.

Automotive Silicone Keypad’s Three Main Conductive Methods

Generally, we use golden pill, nickel pill & low resistance carbon pill for Conductive Auto Rubber Keypad. Conductive Pill is placed at the bottom of the button center, which is activated with printed circuit board when the key webbing is pressed.

Conductive Methods of Automotive Rubber Keypad	Picture	Thickness	Diameter	Resistance	Ways of Putting Conductive Pills
Low Resistance Carbon Pills		0.5-0.6	2, 2.5, 5	<20 Ohms	Location tool
Nickel Pills		0.4-0.6	2, 2.5, 3, 3.5, 4, 5, 6, 8, 10	<5 Ohms	Location tool & manual location
Golden Pills		0.4-0.6	2, 2.5, 3, 3.5, 4, 5, 6, 8, 10	<1 Ohms	Manual location one by one
Cost: low resistance carbon pills ＜nickel pills ＜ golden pill Life Time: low resistan carbon pills ＜nickel pills ＜ golden pill Production Efficiency: low resistance carbon pills ＞nickel pills ＞golden pill

Golden Pill also called Copper Pill, has the best conductivity with the lowest resistance and longest service life among them, but it is the most expensive and time-consuming, requiring workers to put it into the mold one by one , meanwhile it is the most difficult to produce it among them.

Nickel Pill has higher production efficiency than golden pill and better conductivity than carbon pill, but sometimes it needs to be put it into mold by hand rather than tool.

Low Resistance Carbon Pill is the most convenient way to produce as it can be used with tool and put into specific mold hole, so it is also the most economical and fastest way among them. But it has the highest resistance compared to these two conductive methods.

Custom Silicone Auto Keypad Design Guide in Actuation Force

Actuation force also called pressing force, which depends on the design and processing of key webbing. Generally, the actuation force of Auto Conductive Rubber Keypad 200-300±30gram. There are four factors that affect the actuation force, namely slope/ramp, mold processing uniformity, thickness & hardness.

Slope/Ramp: The recommended slope is 45°.

Mold Key Webbing Processing Uniformity: Uneven mold processing will cause the Automobile Silicone Button to be biased towards the thin side of the key webbing when pressed.

Thickness: The thicker the material, the greater the pressing force.

Hardness: The higher the hardness, the higher the actuation force. The hardness of silicone material is generally 50-60 Shore A. If the hardness is too high, the silicone material will become brittle and it will be easily torn, damaged and broken during the demolding.

What are the Advantages & Disadvantages of Shin-Etsu Silicone Rubber Automotive Keypad?

Good Resilience: Auto Silicone Rubber Keymat is a very obvious rebound feeling when pressing.

Excellent Electrical Insulation Performance: Auto Silicone Rubber Keyboard has excellent electrical insulation performance and can remain stable under high voltage.

Strong Safety: Automotive Silicone Rubber Switch has no irritation to human tissue and can be used safely.

Hardness Limit: It is not possible to make high-hardness Auto Silicone Buttons, otherwise it will be brittle and easy to break.

High Cost: Compared with other materials, the cost of Silicone Rubber Auto Keyboard made out of Shin-Etsu silicone is relatively high, which limits its widespread use.

Difficult Processing: It is difficult to refine and difficult to fuse, and special technology is required for processing.