Switch’Air™ 4 legged domes

Thanks to the technology and process of 4-legged Switch’Air™ domes patented by Nicomatic (cushion of air between metal domes), domes do not stick to each other any longer. The placement of components on flexible or rigid circuits becomes more reliable in Pick & Place mode and allows to increase productivity per placed dome.
It is not necessary to use a multi-layer PCB or PCB piercing. Our metal domes are dedicated to membrane switches and all man-machine interface applications with thin thickness.

General features:

  • non-stick Switch’Air™ domes
  • simple and accurate placement by automatic systems
  • high flexibility with 4 packagings to choose from: in tube, in reel, in bulk or on array
  • material: stainless steel with nickel plating, or one-side gold plating: no contamination
  • Temperature of use: -40°C to +105°C
  • Switching voltage: 0.1 to 100 V
  • Switching current 0.005 to 100 ma DC / Power at 1 Watt
  • Contact resistance < 100 mOhm
  • 4 available diameters: 6mm, 8.4mm, 10mm and 12.2mm with or without dimple
  • Activation forces from 110g to 420g (1.1N to 4.2N)
  • Superior Tactile feel (click ration >40%% - 80%) with large sweetspot
  • High Life time up to 5M actuations

It is a patent & trademark of Nicomatic. The Switch'Air dome helps to create a cushion of air between the domes so that they do not stick together. This process ensures an efficient and reliable automatic placement.


There are 2 types of dimple : dimple & micro-dimple. The micro-dimple exists for 6mm domes. Thanks to its small size it allows, in case of dust on the circuit, to eliminate the dust and make the contact.
The dimple on the 8.4mm,10mm & 12.2mm is recommanded for flexible circuits in order to limit the travel.


Nicomatic tests reach up to 10 million activations. We guarantee 1 million activations for 100% of our production. This guarantee can go up to 5 million activations as indicated on our drawings.


- Life expectancy
- Overload test
- Electrical measurements (contact resistance, current capacity...)
- Incoming inspection
- O.S.O test
- Overstroke test
- Sweet Spot test (position of the actuator shifted from the dome centre).


All domes are sold in bulk or on custom made arrays. 4-legged domes are also packaged in tubes (to be used on high speed assembly processes or Pick & Place machines) or tape & reel (8.4, 10 and 12.2mm diameter domes).


By default, the standard dome is delivered in class D. However, it is possible to request tighter tolerances as shown underneath:

A class (upon request):Tolerance center is reduced to +/- 15g (N8.4,N10), and to +/-20g for N12.2.
B class (upon request). Tolerance is never below the trip force indicated in the spec of the D class
C class (upon request). Tolerance is never above the trip force indicated in the spec of the D class
D class = standard dome with standard tolerance


We have 2 recommendations depending on the type of dome:

> Pattern for round domes:  4 and 5mm
> Pattern for 4-legged domes: 6, 8.4, 10 and 12.2mm

Please ask technic@nicomatic.fr


It depends very much on the type of dome usually between 1mm and 1.5mm. Contact us.


No real difference for the tease effect which is the distance the dome needs to travel after clicking before reaching bottom.

N12.2-4L-340-21 Approx. teasing distance = 0.16mm
N12.4L-420-21 Approx. teasing distance = 0.15mm


This is called sweet spot. It can vary depending on the dome size and criteria (click ratio -trip force). Main figures are:
N4 = 0.3-0.5mm
N5 = 0.5-08 mm
N6 =1mm
N8.4 =1.5mm
N12.2= 2.5-3mm
Good to know: the more the actuator is centred the best tactile and life expectancy you get.


Bounce time is under 5 micro seconds.

Bounce definition: When a switch is actuated and contacts touch one another under the force of actuation, they are supposed to establish continuity in a single, crisp moment. Due to the mass of the moving contact and any elasticity inherent in the mechanism and/or contact materials, contacts will "bounce" upon closure for a period of milliseconds before coming to a full rest and providing unbroken contact.


Gold electrolytic is recommanded, but tin plated or screened silver ink can be used.


It is a flat surface 1.5mm dia. actuator.

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