Why we discuss the flexible circuit board material?
There were some guys don’t know flexible circuit board materials.
Special those workers in the FPC line, most of them can not introduce detail.
This paper will discuss the flexible circuit board material with a designer view.
If you have any good idea about the flexible circuit board material, please contact us.
The looser tolerance range due to flexible circuit board material
You know flexible circuit board has high precision circuits than most rigid circuit boards.
We here discuss the looser tolerance range is flexible circuit board outline.
Most flexible circuit boards use Polyimide material, and those materials have less dimensional stability than rigid ones.
Then most of flexible circuit boards will bend flexing, so the outline size was looser tolerance.
In one word, the main reason resulting looser tolerance is due to flexible circuit board material.
Take more care of flexible circuit boards adhesives
If you have read our 4MCPCB article about the stack-up of flexible circuit boards.
You will find most flexible circuit boards contain acrylic adhesives.
This is very special flexible circuit board material, and these chemicals can become soft when heated.
How to solve this problem?
Most flexible circuit board manufacturers will make the pads as large as possible to avoid becoming soft.
The design tips related to flexible circuit board material
There were many tips during flexible circuit board design, but only 3 tips can handle flexible circuit board material issue.
Using space in your flexible circuit board material design.
To ensure statics your flexible circuit board.
Then use anchors also can help stabilize the outer layer.
The last but not least is used teardrops to reduce flexible circuit board stress.
Sometime rich experience flexible circuit board designer also consider using multi-layer designs to solve around adhesive issues.
