Top 6 Considerations When Choosing A Light Touch Switch

January 17, 2018
By Bethany Dunich
6 considerations when designing in tactile switches

A Light Touch Switch, or a Tactile Switch, is used to switch operational signal input in various electronic devices which provides tactile feedback. There is a vast variety of switches available with different characteristics and it can be overwhelming for an engineer to select the best Switch for a particular application. This blog will help point out the most important considerations when choosing a Switch, and should ultimately help to narrow down the search. For even more information, download the full Panasonic Light Touch Switch Design Guide.

1

CLICK FEEL

The Click Feel considers the Switches click ratio and travel. This feature is probably the most important item to consider when choosing a Switch. A tactile switch should provide mechanical feedback to the user and the feel of the switch could also represent the level of quality of the application or product. Panasonic offers a variety of click feelings from a sharp, crisp feeling to a softer, longer travel type.

2

RELIABILITY

Different applications have different requirements in terms of switch cycle life, so it is important to choose a cycle life that fits the application. Panasonic switches have a life cycle that varies from 30,000 to 5 million.

3

PEEL OFF STRENGTH

All external forces that could be applied to the Switch need to be reviewed when considering which Switch to design in. Peel Off Strength is the strength at which the Switch would be sheared from the PCB due to a high force or impact. Different applications have different requirements for being able to withstand impact forces. It is important to select a switch that could handle the appropriate amount of impact for their device. Panasonic’s experience in portable electronic devices has provided the expertise to develop Light Touch Switches with one of the highest peel off strengths in the market.

peel off strength graphic

4

CLICK SOUND

Click Sound should be considered when selecting a Switch for an application. By selecting a Switch with a lower click ratio or lower push force, the Switch will have a lower Click Sound. Some users prefer a quieter Switch while others prefer louder, and it could also depend on the application. For example, a hearing aid (or any Bluetooth connected wearable, such as headphones) would require a quieter switch. Portable or handheld devices would usually have a louder click sound – this helps to confirm to the user that the switch has been pressed.

5

WATER RESISTANCE

If the user’s device will be exposed to certain environments that require water resistance, they should consider a water resistant Switch. Panasonic offers a patented laser welding technology allowing switches to achieve an IP67 Rating while maintaining a sharp tactile feel.

The Switch IP Rating has two numerical digits. The first digit represents the level of solids Ingress Protection with 6 being the highest level of protection, mainly dust. The second digit represents the liquid Ingress Protection. See the chart below.

list of switch protections

6

SIZE

Tactile switches come in a large variety of sizes. It is important to choose the Switch size that will fit into the board space properly as well as to help miniaturize the device overall. Panasonic offers a large variety of switch sizes, including switches as small as 2.6mm X 1.6mm (EVP-BB).

For more information on Panasonic Light Touch (Tactile) Switches or for technical assistance with choosing the right Switch for the application, please contact your local Panasonic sales representative.