design for rigid-flex: rigid-flex circuits combine the best of both worlds.
Real estate in Area Xand y-
Axis, they are z-
Technology to solve their problems.
Current solutions includeto-
Board connector, Pi-Based on flexibility (flex)
Circuit, Pi-based, rigid-
Interconnect of flexible circuits and cables. Board-to-
Board connectors are the most common way to stack 3D because of its pricing and choice of various solutions based on size, density, industry standards and signal integrity (SI)issues. While theboard-to-
The choice of board interconnect seems endless, and they solve the initial problem by consuming valuable PCB real estate.
In addition, the sub-card component needs to contain the matching part of the connector group, which again consumes valuable real estate.
Flexible circuit. Polyimide-
Interconnect solutions based on flexible circuits.
3D solutions emerge one after another, providing the most creative freedom for packaging designers.
According to the latest market intelligence, Flex circuit technology is very popular in some markets. Its price has exceeded $5 billion and it is still growing.
The technology allows static (bend-to-flex)
Whether it\'s a loop or thousands of loops, it\'s a dynamic application.
Flextechnology allows the combination of multiple boards into one PCB, one part number, and a bill of materials (BOM)
Templates, assembly operations, and tests before folding to the final configuration, but there is a price.
The number of suppliers with high material cost, complex tools, long lead time and low output is limited.
The typical price per piece can be three to four times that of ofFR-
4-base rigid pcb. Rigid-
The flexible circuit combines the advantages of both worlds, provides a rigid part for assembly and mechanical assembly, and provides a flexible part for converting signals from one surface in static or dynamic applications.
Unfortunately, they have the same disadvantages as flexible circuits-
Limited suppliers, high cost of materials, complex tools, long delivery time and low production.
In addition, the material does not match between FR-
4 and pi further increase the difficulty of successfully combining these circuits.
This is reflected in three similarto four-
Time price modificationrigid boards.
This can use \"flexibleFR-in\" static \"flex applications-4.
However, the vendor base for this \"patent\" application is further reduced.
Wired interconnect is the lowest technical solution for 3d problems.
They offer maximum design flexibility, easy to build, unlimited length, and fast speed
However, it is labor intensive, difficult to rework, and provides a limited SI solution.
People familiar with rigid PCB manufacturing know that raw materials, thin core materials are very flexible outside the packaging.
It should be noted that this flex part.
In this section, plating holes are used (PTHs)
The transition area needs to be rounded instead of a sharp bend.
Free book by Joe Fjelstad \"flexible circuit technology-3rd Edition\" (1).
Many design constraints are explained by the manufacturing process.
Design and manufacturing is the first part of the puzzle, but in the market acceptance, the final product needs to be fully tested according to accepted industry standards-
In this case, IPC-TM-650 9 (see FIGURE 1).
This test requires the flexible substrate to repeatedly fold the metal rod of the specified diameter until it fails.
Static applications using flexible FR-
4 Reliability with 77-Display
Life elasticity of 634, usually exceeding the requirements of most static applications. Rigid-
Flex applications are one of the most attractive 3d interconnect architectures.
Innovative use of new materials makes these applications more cost-competitive for traditional boardsto-
By using existing rigid PCB manufacturing processes and technologies, coupled with some new twists and turns, manufacturers are now able to offer a solution that saves customers 30% to 70% of their current cost per piece. REFERENCES (1. )
Joseph, \"flexible circuit technology\" 3 rdEdition. Jan. 2009. (2. )
\"Flexible FR-4: A Low-
Cost replacement for Pi
Journal of circuits, June 2004.
Happy Hortons is forMentor graphics, a senior technical expert who recently retired.