Skip to main content

Membrane Switch Design Guide

Since membrane switches are custom designed to meet specific applications, each product will have its own criteria to meet. JRPanel has used its more than 20 years of membrane switch experience to compile some of the most critical guidelines to designing and specifying our products. The use of these guidelines will help ensure that all aspects of product design are considered as to maximize the aesthetic quality, reliability, and efficiency of the final product. 


Genral Considerations


Enviromental:

 
What temperature and humidity range will this product experience?


What types of contaminants or chemicals will come into contact with this product?


Will this product be subjected to moisture and/or U.V. exposure? 


Electrical: 


How many contact points will there be?


What type pinout or matrix will be used? (common bus, X-Y matrix)


What closed loop resistance will be acceptable?


Will electrostatic or EMI shielding be necessary? 


Mechanical:


Will tactile response be required?


To what material will the switch be laminated?


What number of actuations will this product receive?


Will actuation force be a factor? 


Appearance:


Will edges be exposed, recessed, or covered with a bezel?


Will embossing be required?


Will there be different parts to the same product? (sets)


How many colors will be needed? 


Basic Membrane Switch Construction



Basic Membrane Switch Construction


Graphic Design and Preparation 


Graphic Design Sample


Blueprints – Provide drawings that clearly dimension all physical characteristics including color breaks and copy.


Colors – Identify colors by using Pantone (PMS) color number or a color sample. It is important to supply the exact standard for which our color match will be evaluated. Be cognizant of how colors contrast with one another in order to maximize the legibility of the text and symbols. 


Background – Dark backgrounds and light text will provide greater clarity and show less wear and dirt.


Artwork – It is possible for customers to supply useable artwork, but they should consult JRPanel first to ensure that proper artwork specifications are met.


Borders and Outlines – Avoid outlines close to cutouts or outer edges, or circles within circles, as any misregistrations will be visually accentuated. 



Text – Block lettering provides the most legible copy. Try to use common fonts. When logos or symbols are used, it is best to supply film positives or accurate black and white artwork for JRPanel to scan. Positive letter strokes should be a minimum of .008” and .012” for negative letter stroke.


Embossing 


Raising certain areas of the graphic overlay can offer a unique look to your product as well as provide an important function.  JRPanel can emboss graphics in two ways: Metal Dome and Die Pressing. 


Metal Dome


It is a stainless steel dome that assembly in the upper circuit layer. When press the keys, it will be connected with the beneath circuit. It will have a tick sound and with a good feeling of bouncing. The life circle is about 2 million times. No need to make mould.



Metal Dome


Die Pressing


It is embossed silver pad that on the upper circuit layer, when press the keys, it will be connected with the beneath circuit. For this kind, when pressing, there is no sound. The life circle is about 5 million times. For batch orders or too many keys in 1 membrane switch, it needs to make die pressing mould.



Die Pressing



Creating a blueprint for a membrane switch? Don’t forget these important specifications!


Overall size of part
Keypad centers
Diameter of corners
Size and Location of Cutouts
Size and location of windows
Location of tail exit point
Location of graphic entities
Electrical schematic
Identify “pin 1”
Color specifications
Tail Length


Embedded LEDs 


As a substitute to mounting LEDs on a sub-board, JRPanel can provide membrane switches with LEDs embedded inside the membrane switch. This method can prove very effective particularly when a printed circuit board is not needed directly behind the membrane switch.
 
Due to the profile of a surface mount LED in relation to the thickness of a membrane switch, it may be necessary to emboss the graphic overlay to accommodate the thickness differential. JRPanel can use several standard LEDs for this application. 



 Embedded LEDs


Backer Adhesive Selection


A wide variety of pressure sensitive adhesives are available to bond the membrane switch to a substrate. Selection of the best adhesive will depend upon such factors as environmental conditions, type of substrate (metal, plastic, paint) and smoothness of the surface. In general, low surface energy materials as well as rough surfaces provide more difficult substrates for which to adhere. Here is a guideline of the surface energy of several popular substrates (in dynes/cm).



Backer Adhesive Selection

Comments

Popular posts from this blog

Identify Different Types of Transformer Cores, Based on Materials

  Hi guys, this is JRPanel ! In previous  blog s, we have introduced several points about High Frequency Transformer, like  bobbins  and  Flat Spiral Coil . In this blog, JRPanel would like to introduce the commonly used magnetic cores in transformers ,  based on materials.   Generally speaking, the material of the core determines the environment in which the transformer is used. A transformer that uses a core of a different material will have its performance affected, may even be non-functional.   By material, magnetic cores are generally divided into the  several  categories . JRPanel will introduce them one by one to help you understand more fully.   1. Manganese Zinc Ferrite Core Mn-Zn core is a soft magnetic core with high initial permeability (2000~15000). The higher the initial permeability, the lower the surface resistance, so it is generally used in circuits below 1 MHz. Mn-Zn core has a high saturation flux density and causes lower losses, making it one of the most desirable

The Relationship Between Plastic Nameplates and Membrane Switches

Before the 1970s, most nameplates   were made of metal materials. Today, plastic  nameplates   have been widely used in household appliances, instruments, meters, office equipment and other fields, and have become an indispensable part of electromechanical products. It not only plays the role of trademark identification, specification model, function indication, etc., but also becomes an element that reflects the appearance of the product.   With the continuous use of new materials and new processes, the surface of plastic  nameplates   is constantly improving, and it has become the crystallization of three major technologies: comprehensive surface treatment, processing and molding, and screen printing.   Plastic  nameplates   can be divided into 2 types according to their material processing methods and objects of use:   1. The injection-type plastic  nameplate   is made of ABS, PC and other engineering injection molding, and then undergoes secondary surface decoration processing such

The Main Use and Classification Methods of Transformer Bobbins

  Hi guys, this blog is still about   high frequency transformers .   JRPanel   would like to introduce you the main use of transformer bobbins and how we classify them.   In the pictures are the transformer bobbins.        Following are the main uses of that JRPanel has summarized for you:   1. The bobbins provide space for winding copper wires in transformers.   2. Wire channel in the bobbins provides path for transformer winding.   3. The bobbins help to fix the core in the transformers.   4. The metal pins in the bobbins are connected to the  PCB  after soldering, which play an important role in conducting electricity when the transformer is working.   5. The baffle at the bottom of the bobbins isolates the core from the tin stack to avoid poor volta ge resistance.       From this it can be seen that the importance of bobbins in transformer is extraordinary.   After understanding the main uses of transformer bobbins,  JRPanel  is to introduce its common classification methods.   Fi