Answer：The Metal Dome Keypad differs from the Mylar Dome in so far as the tactile feel is obtained by inserting a metal dome in between the Graphic Overlay and the Lower Circuit. This then gives a more 'clicky' tactile sensation when the switch is pressed.
It offers a cost effective solution to those designers who want more of a tactile feel. (However, due to the extra work and material will inevitably cost more than the Mylar Dome Keypad).
Again, with an operating life of greater than one million closures, this is a very frequently chosen option.
Ask：ASTM Membrane Switch Standards
Answer：ASTM Membrane Switch Subcommittee F01.18 has created a series of electrical, mechanical, environmental, cosmetic and aesthetic tests that world-wide manufacturers can use to prove their switches meet customer needs.
Low-cost test methods are a boon to membrane-switch manufacturers and purchasers, and Subcommittee F01.18 has developed 25 standard test methods that cover switch life, tail creasing, dielectric withstand and thermal shock, standard terminology for membrane switches, and more.
According to committee member Dennis Webster, both membrane manufacturers, and original equipment manufacturers who purchase custom membrane switches for their product, must know what specifications their switch will meet. “As an OEM, these are the methods that should be on your drawings and those against which you insist upon receiving verification documentation,” says Webster, an engineering manager who has worked with membranes for 20 years. “As a manufacturer, these are the methods you should incorporate within your facility, validating that you are a quality vendor.”
The subcommittee also welcomes participation on a task group that is drafting standard test procedures for electroluminescent lamps. To learn more about ASTM’s membrane switch standards or participate on the task group, contact chairman Alan Burk , ALMAX, Kirkland, WA phone: 425- 889-9417 or Click Here for information on Joining ASTM.
Ask：Membrane Switch Definition - 5 conditions
Answer：The ASTM subcommittee on Membrane Switches defines a membrane switch as: "A momentary switch device in which at least one contact is on, or made of, a flexible substrate"
To be more specific, all of the following conditions or features must be met in order to truly be classified as a membrane switch:
1. Direct (Ohmic) Contact: the poles of the switch must make physical contact, i.e. can not be non-contact type like capacitive, ferrite core, or hall effect.
2. Momentary Action: Upon release, the poles immediately separate as the flexing membrane returns to its original position.
3. Low Voltage Application: A membrane switch is designed to be used in low voltage, DC logic-level-signal, applications.
4. Membrane Layer: A thin pliable layer and carries one pole, both poles or that flexes during switch operation used to short both switch poles together. See figures 2 & 3.
5. Static Layer: Does not flex during switch operation but carries one pole, both poles or used to short both switch poles together. See figures 2 & 3.
Ask：What's Tactile Membrane Switches?
Answer：Standard configration tactile membrane switches with stainless steel domes. These switches are versatile as well as durable and can be used in any application where membrane switch technology is appropriate. Ideal for Prototype or production requirements. These standard configurations can be arrayed with other switches in this series to create more complex key arrangements. Can be used with screenprinted or digitally produced graphic overlays. A polyester graphic overlay film is recommended
All switches in this category meet the following specifications:
Contact Rating- 15V , 5 mA * Resistance- 150 ohms max *
Contact Bounce- 10 msec * Operating Temp- 0 to 50 C *
Storage Temp- -25 to 70 C * Life- 1 million cycles * Force- 450 G
Ask：Do you have local distributors in our area?
Answer：We do not use distributors. We see no reason why you should have to deal with a middle-man when you can buy directly from the manufacturing source. We ship worldwide every day, by any shipping method you prefer. All of our products are manufactured entirely at our facilities in Dongguan, China, Contact Us to set up an account.
