Views:28 Author:rubber-keypad Publish Time: 2019-09-27 Origin:Site
Metal Dome made of stainless steel, is an important part of the switch. With the conduction of the metal dome, it plays a high-quality switch between the operator and the product. At the same time, the use of the stable resilience of the metal dome (automatic return after pressing), and the long life, provide the operator with high-quality tactile feedback. The metal dome is mainly used in a membrane switch with printed circuit board and silicone rubber keyboard.
Compared with the conventional silicone button, the conductive metal dome array has a better touch feeling, a longer life, and can indirectly improve the production efficiency of each type of switch using the metal dome array. The metal dome on the silicone rubber keyboard is located on the conductive part of the PCB (mostly above the gold finger on the circuit board). When pressed, the center point of the metal dome is concave and contacts the line on the PCB to form a loop. When the current is passed, the entire product can work normally.
According to different product structure and grade requirements, the metal dome can be nickel-plated, silver-plated, gold-plated and other different surface treatments.
Metal dome can be divided into different shapes
Metal dome different structure
Single layer structure
This is the originally simplest structure. The metal dome is located under Mylar (a layer of adhesive PET ) and has a vent to ensure basic feel and use.
Double layer structure
Compared with single-layer structure, it has a extra spacer that is better attached to Mylar and has good contact with the PCB. It has a better feel (somewhat similar to a membrane switch). In addition, the vent hole on the double-layer structure conductive membrane is more effectivel to prevent PET layer from being scratched by metal dome’s burr, and also prevent dust from entering the PET layer.
There is a layer of silver paste on the top of Myalr – ESD (Electrostatic Discharge Control). EMI is mainly used for preventing the target appliance from damage by static electricity ,which is generated by electrons and their peripheral products.
A layer of rubber glue (silicone glue) is printed on top of the Mylar or EMI layer, so this type of product can be firmly stick on PCB/FPC circuit boards.
Metal Dome Application
Metal dome is mainly in mobile phones, internet telephony, various remote controls, MP3/MP4, radio, digital cameras, learning machines, game control keyboards, microwave ovens, car dashboards, telescopes, toys, etc. It has a better feel and a longer service life than previous membrane switch.