Technical Support
►Metal dome membrane switch

(Equipped with a unique four-legged shape, these innovative dome switches offer enhanced durability, reliability and versatility while maintaining exceptional tactile feel for single or double-sided printed circuit boards, flex circuits, and membrane switch panels.  Offered in Mini (.331” Dia), Compact (.394” Dia) and Maxi (.480” Dia) styles with trip forces from 7.8 oz. to 14.8 oz.)

Construction of metal dome membrane switch and its circuits design

Working principle of Metal Dome Membrane Switch

The deformation of the metal dome causes the connection of anode and cathode when press the key. That is how the switch work.
(They function in the following way: The metal domes are placed on the printed circuit board by means of pressure-sensitive adhesive tape. In their relaxed state, the metal domes rest on the outer rim of the primary pathway. When pushed, the domes collapse and make contact with the secondary pathway, thereby closing the circuit.)

Common shapes of metal dome and its specifications
1 Four legs 6mm,8.4mm,10mm,


2 Four legs with hole
3 Triangle
4 Round
Four legs: Four leg series metal domes (4-leg tactile metal domes, cross metal dome)

      1                             2                               3                             4

Four legs with hole: 

Triangle: (triangle tactile metal domes)

Advantages of metal dome membrane switch
Multiple shapes can be applied to different custom designs 
Meal dome is contact well and low resistance
Stable form assure the same key pressure on multi-button panel.
Distinct hand feeling give clear feedback when pressing.

(These snap action switches provide positive feedback with an audible and tactile click.)

 Electrical Performance
Item Data Item Data
1.Wire Resistance 0.5mm width,<1Ω/cm 2.Rated Current 25-200mA,0-30V DC
3.Insulation Resistance >100MΩ 250V DC 4.Working Voltage <50V DC
5.Working Life >0.5 million times 6.Working Temperature -30℃-50℃
7.Working Humidity 40℃,98%RH No Influence 8.Feed backTime 10ms

The metal dome should be assembled on flat interface and cannot be bent.
The metal dome, which has been fixed on the circuit, cannot be reused.
Do not stock the metal dome under heavy pressure in case of the deformation of panel.
Do not hit the key by hard object.