Top Quality

Flexible PCB

From simple applications to the most complex, the versatility of flex circuits boards is unmatched. As a connective device, the primary benefits of designed circuits compared to traditional cabling and rigid boards include:
* Unparalleled design flexibility
* Higher circuit density
* More robust operating temperature range
* Stronger signal quality
* Reduced wiring errors
* Elimination of mechanical connectors
* Improved reliability and impedance control
* Size and weight reduction

 

 

Air Gap

Air Gap - Through the process of selective bonding, increased flexibility is achieved by "unbonding" layers so they are allowed to flex freely. We are capable of designing and fabrication for this air gap technology allowing your designs more flexibility.

Shielding

Shielding is applied when an application requires limits in electromagnetic and/or electrostatic interference. Protective shielding can be patterned or solid. Either way, it reduces noise and controls the impedance of signal lines.

Panelisation / Stiffeners

During the panelisation process a stiffener is applied to the boundaries of multiple circuits on a panel so that they can be easily processed through the "pick & place" and wave soldering processes. Once the panel of circuit boards is done, simply clip them out and they are ready to go. Stiffeners are applied to flex circuits where additional support is needed such as areas of component assembly or underneath exposed traces that will be plugged in for connection. Common stiffeners are FR4 and polyimide.

 
Flexible Circuits Features
Capabilities

Specification

Single Side /  Double Side/  Multi-Layer 

Maximum Size 250x 500mm
Minimum Spacing Between Circuits 3 mil
Minimum Annual Ring 4 mil
Peel-Off Strength 1.0N/mm
Standard Line Width: 0.25mm, Minimum Line Width: 0.10mm
Standard Trace Pitch: 0.5mm, Minimum Trace Pitch: 0.2mm

Drilling

Single Side /  Double Side : 0.1mm

Multi-Layer  : 0.15mm

Tolerance: +/-0.05mm

Plated Holes

12~25um +/‐2.5um

Min trace width & spacing

2.5mil/2.5mil (1/2oz)

Thickness Tolerance

Single Sided 0.013mm
Double Sided 0.025mm
Hole Dia. Tolerance(PTH) ±0.05mm
Outline Tolerance ±0.1mm

Materials

Base Material and Thickness Polyimide (0.025mm , 0.050mm) or Polyester (0.076mm, 0.127mm)
Conductor (Copper-RA or ED) 1/3oz, 1/2oz, 1oz
Coverlay Layer and Thickness Polyimide (0.025mm), Polyester (0.050mm)
Stiffener Material FR-4, Mylar or Kapton

Other Specification

Covercoat Thickness: 0.4mil to 0.7mil ( Liquid Solder mask or Coverlayer ) / Mask Dam 7mil (Min) Slot 40mil / Exposure Registration +/-3mil
Silkscreen / Legend 5mil (Minimum )
Surface Treatment Immersion Tin, Immersion Gold (ENIG ), Electrolytic & Electroless soft (Bondable ) Gold, Immersion silver, OSP (Entek)
NPTH Ø=0.1mm (Drilling ) 0.5mm (Punching hole) / Registration +/-3mi / Tolerance +/-3mil
Mechanical Process Punching Tool, V-Cut
Testing Methods O/S Testing
Controlled Impedance +/-10%
Final Products Inspection Visual Inspection 100%
Certification UL 94V-0 , RoHS, SGS Inspection
Packing Method Zipper or Vacuumed Sealed Pack

Standard production process flows
1Cutting Shearing

2 CNC Drilling

2-1 CNC Drilling

3 PTH

3-1 PTH

4 Dry Film Lamination

5 Exposure

5-1 Exposure

6 Development

7 Pattern Etching

8 Dry Film Stripping

9 Pre-lamination Coverlayer

10 Hot Press Lamination Coverlayer

11 Surface Finishe

12 Printing

13 Testing

14 Assembly Punching

15 Inspection

16 Packing

Contact Us : pcb@welsa.com

11 Surface Finishe