considered when specifying shielding requirements.
Tail Exit Point
Flexible membrane switches are connected by means of a flexible tail that is cut from the circuit material. We have a great deal of flexibility in selecting the exit point. The tail cannot exit under or within .125" of the active keypad area.
Interconnect
The flexible tail that exits a membrane switch usually has single row traces on
.100" centers. This tail can be connected to a circuit board with many different single row connectors designed for flex circuits. Holland Nameplate is tooled to crimp AMP, Berg, and Molex connectors onto flex circuits.
The most common type of Berg connector used is the Berg Clincher (65801). This is a female single row connector with contacts on .100" centers. The Clincher system is also available in a male version, part number 66226. The AMP system is a two component system. The contacts are specified separately from the housing. The flex circuit can also be terminated with solder tabs that can be directly soldered onto the circuit board. The AMP part number used is
The lowest cost alternative is to use a ZIF (Zero Insertion Force) connector. AMP and Molex both offer ZIF connectors. When using a ZIF connector the membrane switch is shipped with exposed contacts on the end of the tail. The customer then inserts the tail into the ZIF connector. ZIF connectors are available with locking mechanisms in both .100" and .050" centers. When using a ZIF connector, you should specify either the connector or the requirements for the connector.
Screen Printed Flex Circuits
The typical flex circuits used in membrane switches are made with screen printed
This type of circuit does not utilize feed thrus, so circuits are single sided. Traces can cross through use of a dielectric crossover. This increases the number of printing operations, and consequently increases cost. A dielectric material is screen printed in the area the trace will be crossed over, and then silver jumpers are printed on top of the dielectric.
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