Supports or supports are frequently utilized to support components on flex circuits. These important attachments can be fabricated from a large range of materials depending upon design demand (i.e., low weight, finest heat sinking, cheapest expense, finest spring top qualities). Both conductive as well as protecting materials can be made use of to provide rigidity to a flex PCB. Stiffener products include, yet are not restricted to:

– Resin-glass laminates– a typical call-out, easily available and beneficial in many applications, specifically for much heavier element support.
– Extra layer of coverlayer– another typical call-out, readily offered to the manufacturer. Beneficial for support of smaller, lighter weight components.
– Thermoplastic sheet– similar to material glass laminates, however could not be useful at greater temperature levels depending on material kind. Can perhaps be used to warmth form the assembly.
– Beryllium copper– a spring steel frequently used in ports as well as a feasible twin function option as a ground or as a resistant base.
– Stainless steel– common selection in disc drive suspension circuits for read-write heads.
– Anodized light weight aluminum– anodizing makes the surface an insulator while the light weight aluminum core can work as a warmth spreader.
– Injection formed bases– offers prospective to develop circuit over a predetermined form.
– Glasses– have feasible benefits where optics are involved, however are brittle.
– Refractory materials– helpful as shielding bases where high thermal conductivity is preferred, yet are fragile.

In addition to the flex PCB products detailed, the bundle or box into which the flex circuit is to be positioned can likewise function as the stiffener if the design enables. Along with simple component support, the bundle itself can be utilized for heat dissipation. While this is an eye-catching option for a variety of applications, if repair service is needed, it can be challenging because elimination of the flex circuits from the product packaging could cause damage.

SPECIAL TECHNIQUES FOR STIFFENERS

Special design techniques permit supports to work as greater than just part support. For instance, stiffeners can be designed to help assembly by allowing the flex PCB to be put together as a virtually rigid board. There are a selection of methods that could be thought about.

PATH AND RETAIN STIFFENERS

Option and also maintain supports are created by NC routing of the substratum, leaving it affixed in specific areas for easy elimination later on. Gang assembly or mass application of supports in panelized form promotes both the application of the flex PCB to the support and subsequent component assembly. This strategy enables the support to be snapped off or trim after assembly. When the flex PCB and also stiffener are bound with each other, the resulting flex PCB panel can be processed similar to a rigid board. The adhesive is used oversized and cut to dimension throughout the routing step. While routers are prevalent in PCB manufacturing, lasers and also water jet cutters are also sensible manufacturing options for preparing or pre-cutting stiffeners.

GO BACK TO WEB PUNCHING

Go back to web punching (also referred to as strike out, type) of the support needs special strike tooling whereby the rigid material is punched from the panel and right away pressed or punched back right into its initial placement in the panel. The method is generally used for economical rigid boards as well as permits mass assembly with fairly easy assembly component needs.

RACKING UP OR DICING OF STIFFENERS

Using racking up or dicing tools to prepare the support panel is possible if features of the flex PCB design permit.

Relative to the scoring procedure, the circuit and/or the support is cut partially through utilizing special devices to cut at a controlled deepness straight course with the rigid material alone or via both flex circuit and rigid base. After assembly the circuits could after that be broken apart along the score lines.

As opposed to the routing concept, dicing requires reducing completely via the circuit as well as stiffener. As a result of the nature of the tools made use of, all product cuts should be made in a straight line as well as orthogonal to the significant (X as well as Y) measurements of the panel.

ADHESIVES FOR BONDING OF STIFFENERS

All of the bonding adhesives used to develop flex circuit laminates are candidates for connecting a flex PCB to a support. The choice of which sticky to use is frequently based on efficiency requirements.

Along with the adhesives made use of in typical flex PCB manufacturing, there are various other sorts of adhesives that can be utilized. The designer should discuss choices with and also obtain referrals from the flex PCB manufacturer .