Surface-mount device dome can be soldered in a standard SMT process

Snaptron has released its first surface-mount metal dome, the SG-Series, also known as a surface-mount device (SMD) dome. The series is a standard four-leg metal dome switch with two solderable tabs. The tabs enable the dome to be soldered directly to a PCB or flex circuit without impacting performance. Like conventional tactile domes, the solder dome is a normally open momentary contact that offers a crisp tactile feel, letting the user know a button was pressed.

Conventional methods of adhering metal domes to the circuit board need adhesive tape or placement into spacer pockets. This process is generally achieved semi-automatically or manually and needs an assembler. A major benefit of a solder dome is the simplicity of assembly and the capability to utilise existing SMT equipment to place these domes. This solution takes the time and cost of manual labour out of the equation.

The solder dome has a higher life cycle rating than most tact switches. For example, tact switches are usually rated to 500,000 cycles, while the solder dome is rated to 1,000,000 cycles – ideal for applications with longer life demands. It also has a far lower profile and better tactile feel – providing a distinct advantage over solderable tact switches. Consequently, SMD domes are a viable option for tact switches.

The device lets customers integrate dome placement in their current SMT systems or normal automation processes. The solder dome can be soldered using the reflow method and other components. As a result, they can lower labour costs, speed up production, and eradicate steps to final assembly. Because of this, they are often a go-to solution for high-volume projects.

"A dome that can be soldered directly to the circuit board has been a highly sought-after solution by our customers," said Ashley Steinbach, director of Strategic Development at Snaptron. "We're excited to bring this product to the market and offer our customers a switch that can be soldered in the assembly line, like any other component." Steinbach continues, "Once the SG-Series is fully released, we expect to double our volumes and see this significantly impacting the tactile switch market."

The solder dome is now available in 6.3mm size. The company is scheduled to release many other sizes, including 5.3mm, 7mm, 8.5mm, 10mm, 12mm, and 14mm, in the coming months.