Epec's Blog | Electronics Manufacturing Solutions

As the benefits and capabilities of vendor outsourcing continue to grow, it becomes more important to know what to look for before committing to outsourcing. Developing a sound evaluation approach while knowing what questions to ask of potential suppliers helps maximize efficiency, saving time and money down the road.

As custom manufactured cable assemblies have grown in complexity, it has become far more common to see various electronics integrated directly into the finished design. The inclusion of electronics into a cable assembly design can consist of adding a switch, PCB, LED, or a multitude of other components. Once added, these components offer a much higher level of sophistication to the cable assembly while allowing the included electronics the ability to withstand a much more rugged working environment.

The flex PCB stack-up documentation is an important component of the data set of a flexible printed circuit board design. It consists of a description of a flex or rigid-flex circuit board that defines in detail the specific material requirements and construction of the design.

Many electronics assemblies that utilize flexible printed circuit boards are sensitive to either absorbing or emitting electromagnetic interference (EMI). If EMI is left uncontrolled it can negatively impact the performance of the design and in extreme cases completely prevent it from functioning.

With the uncertainty the global economy has brought over the last decade, it has been challenging for many companies to balance the fine line of just-in-time (JIT) inventory management, being line down, and being over budget on inventory numbers. We live in a world where next day delivery of virtually anything has become a guarantee, or at least an expectation.

The pre-baking of flex printed circuit boards (PCB) immediately prior to assembly is an industry standard requirement that is documented in IPC2223 sec 5.3.5, IPC-FA-251 sec. 3.2.1.1.2 and by material suppliers (i.e. DuPont Pyralux Technical Manual sec. 5.23). This applies to all polyimide-based flex and rigid–flex designs. But why is pre-baking done prior to assembly, rather than earlier in the circuit board manufacturing stage?

When ordering flex circuit boards online, quick turn order delivery timelines can incur setbacks if the data set is either incomplete or if the design has technical issues. Technical issues can be related to either manufacturability or the end use of the parts. These issues then often require multiple communications to resolve and in some worst-case scenarios, extensive design revision. Any of these issues will of course delay the delivery of the finished parts.

The reason printed circuit boards (PCBs) require a surface finish rather than being left as simply bare copper is because while copper is an excellent conductor, leaving it exposed will cause it to oxidize and deteriorate over time. The increased exposure will cause the PCB to fail much sooner than expected.

EMI (electromagnetic interference) and RFI (radio-frequency interference) are disturbances generated by external sources that impact a cable assembly by degrading the assembly's performance or completely preventing it from functioning. These disturbances can cause problems ranging from an increase in error rates of the signal being transmitted through the assembly to total loss of any electronically readable signal.

A printed circuit board (PCB) is an inexpensive and compact way to create many of the necessary interconnects between RF components in a subsystem. The interconnects are most often created with stripline and microstrip transmission lines, as well as vertical coaxial transmission lines created with plated through hole patterns.