Flexible Printed Circuit Board Overview

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What is Flexible PCB?

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A Flex PCB or FPCB is a patterned arrangement of printed circuitry and components that utilizes flexible based material with or without flexible coverlay.

 

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Types of Flexible PCB

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There are a few basic types of flexible circuits but significant variation between the types in terms of their construction. Following is a review of the most common types.

 

1.SINGLE-SIDED FLEX PCB

Single-sided flexible circuits consist of a single conductor layer of metal or conductive (metal-filled) polymer on a flexible dielectric film. It can be fabricated with or without protective coatings such as cover layers or cover coats;

 

2.DOUBLE ACCESS OR BACK BARED CIRCUITS

Double access (also known as back bared) flex PCB has a single conductor layer that makes features of the conductor pattern accessible, such as lead terminations, from both sides.

 

3.DOUBLE-SIDED FLEX PCB

Double-sided flex circuits have two conductor layers. They can be fabricated with or without plated through-holes, though the plated through hole variation is more common.

Depending on design requirements, double-sided flex circuits can be fabricated with protective cover layers on one, both, or neither side of the completed circuit.

 

4.MULTILAYER FLEX PCB

Flex PCB with three or more layers of conductors is known as multilayer flex PCB. Commonly, the layers are interconnected by plated through-holes, but this is not required because it is feasible to built openings to access lower circuit level features. The layers of the multilayer flex circuit may or may not be continuously laminated together throughout the construction with the exception of the areas occupied by plated through holes. Discontinuous lamination is common in cases that require maximum flexibility and is accomplished by leaving the areas where flexing or bending is to occur unbonded.

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What Advantages FPCB Has Versus Rigid PCB?

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• More compact, lighter design,
• Shorter assembly time
• Lower Assembly cost
• Fewer Assembly Error 
• Higher system stability
• Better heat dissipation 
• 3D interconnection and packaging
• Better Signal Reliability

 

 

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Flexible PCB Production Flowchart

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Why Choose XPCB as Your Flex PCB  Supplier?

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Feeding on over 10 years of PCB fabrication & assembly experience, XPCB Limited has grown to be an exceptional team at FPC fabrication.  Check out our capacity chart below

 

Feature	Capability
Quality Grade	Standard IPC II, IPC III
Number of Layers	1 – 12 layers
Order Quantity	1pc – 10000+pcs
Build Time	2days – 5weeks
Material	PI (PoIyimide), LCP (Liquid Crystal Polymer)
Board Size	Min 1*6mm, Max. 500*1200mm
Board Thickness	0.1mm – 0.8mm
Copper Weight (Finished)	0.5oz – 4.0oz
Min Tracing/Spacing	2mil/2mil
Solder Mask Color	Green, White, Blue, Black, Red, Yellow
Solder-stop coating—Soldermask oil	Green, White, Blue, Black, Red, Yellow
Solder-stop coating—Coverlay	PI and PET film
Silkscreen Color	White, Black, Yellow
Surface Finish	ENIG – RoHS ENEPIG (Electroless Nickel Electroless Palladium Immersion Gold, Soft bonding) OSP – RoHS
Min Annular Ring	0.075mm
Min Drilling Hole Diameter	0.01mm
Min. hole size—Drilling (PTH)	0.05mm
Min. hole size—Punching (NPTH)	0.5mm
Tolerance of dimension	±0.05mm
Other Techniques	Gold fingers Peelable solder mask Copper Filled Plating EMI SHIELDING (Silver Ink, Silver Film) Stiffener (PI / FR-4 / SUS material)