Ever-smaller switches for wearables: dust & water resistant

October 09, 2015 // By Graham Prophet
Alps has added to its product lineup the “SKSWD Series” TACT Switch with IP68 dust and water resistance, for integration into wearable computers, healthcare devices and smartphones.

Electronic devices worn on the body such as wearable computers and healthcare devices are becoming smaller and increasingly sophisticated. Often exposed to sweat and rain, dust and dirt, these devices require components which are light and compact and achieve high dust and water resistance.

The SKSWD Series TACT Switch is in the industry’s smallest class and provides high dust and water resistance (IP68). It has compact dimensions of 3.0 × 2.0mm and a low profile, with a height of 0.6mm.

Switches of around this size for use in mobile devices, says Alps, generally have an IP67-equivalent dust and water resistance rating. For the SKSWD Series, however, ALPS used original design and manufacturing technology to achieve even better dust resistance and an IP68 rating without making any major structural changes to the product, thought to be a first for compact switches with a similar configuration.

To ensure sound reliability, a projection structure was adopted for the metal contact. This both prevents differences in feel caused by position variations during installation and enables stable operation of the switch even when it is pressed from the edge or diagonally. The projection structure used is an “inner projection.” This increases projection strength, thereby improving durability and facilitates handling during installation.

Parameters include;

Dimensions (W×D×H) - 3.0 × 2.0 × 0.6mm

Operating force - 2.4N

Travel – 0.13 mm

Operating life - 300,000 cycles

Rating (max.) - 50 mA @ 12V DC

Contact resistance - 500 mΩ max.

Protective structure - IP68

Alps Electric; www.alps.com