Clarifications of FPC
According to the combination of base material and copper foil, flexible circuit board can
Be divided into two types: flexible board with adhesive and flexible board without adhesive.
the price of non-adhesive flexible PCB is much higher than that of adhesive flexible PCB,
but its flexibility, bonding force between copper foil and substrate and flatness of solder
Are also better than that of adhesive flexible PCB. So it is only used in the high demand
Situations, such as the: COF (CHIP ON FLEX, flexible board with bare chip, the high flatness
of the pad) and so on. Because its price is high, most of the flexible PCBs used in the market
Are still adhesive flexible circuit board. Because the flexible circuit board is mainly used in the
Situation where bending is required, if the design or process is not reasonable, it is easy to
Produce micro-cracks, welding and other defects.

Economy of using FPC
If the circuit design is relatively simple, the total volume is small, and the space is suitable,
the traditional internal connection is much cheaper. Flexible circuits are a good design option
If the circuit is complex, processes many signals or has special electrical or mechanical
Requirements. When the size and performance of applications exceed the capacity of rigid
Circuits, flexible assembly is the most economical. A 12mil pad with a 5mil through hole and
A flexible circuit with 3mil lines and spacing can be fabricated on a thin film. Therefore, it is
More reliable to mount the chip directly on the film. There is no flame retardant that could
Be an ion source. these films may be protective and solidified at higher temperatures to
Obtain higher glass transition temperatures. Flexible materials are less costly than rigid
Materials because they are free of connectors.



FPC Case: Assembled Flexible PCB Built on 0.15mm
Polyimide (PI) with Immersion Gold
(Flexible printed circuits are custom-made products, the picture and parameters shown
Are just for reference)

General description
this is a type of assembled flexible PCB built on polyimide substrate with Tg 60C for the
Application of Portable Sound System. It's 2 layer FPC at 0.15 mm thick, white silkscreen
on yellow coverlay (solder mask) covering both sides and immersion gold on pads. Polyimide
as stiffener is on the back of one end. the base material is from Shengyi, entire board supplying
34 PCBs per panel. They're fabricated per IPC 6012 Class 2 using supplied Gerber data. Each 25
Panels are packed for shipment. 

Parameter and data sheet

PCB Size:	29 x 4.0mm, 121 x 75.5mm=34 pcs
Number of Layers	2 layers
Board Type	Flexbile cirucit
Board Thickness	0.15mm +/-10%
Board Material	Polyimide (PI) 25um
Board Material Supplier	Shengyi
Tg Value of Board Material	60
PTH Cu thickness	20 um
Inner Iayer Cu thicknes	N/A
Surface Cu thickness	35 um (1oz)
Coverlay Colour	Yellow
Number of Coverlay	2
Thickness of Coverlay	25 um
Stiffener	Polyimide 0.3mm
Type of Silkscreen Ink	Taiyo
Supplier of Silkscreen	Taiyo
Color of Silkscreen	White
Number of Silkscreen	1
Minimum via (mm)	0.3
Minimum Trace (mil)	8.0
Minimum Gap(mil)	7.3
Surface Finish	Immersion Gold
RoHS Required	Yes
Famability	94-V0
Thermal Shock Test	Pass, -25125, 1000 cycles.
Thermal Stress	Pass, 3005,10 seconds, 3 cycles. No delamination, No blistering.
Function	100% Pass electrical test
Workmanship	Compliance with IPC-A-600H & IPC-6013C Class 2
Type of artwork to be supplied	Email file, Gerber RS-274-X, PCBDOC etc
Service area	Worldwide, Globally.

Features and benefits
Excellent flexibility;
Reducing the volume;
Weight reduction;
Consistency of assembly;
SMT process is resistant to reflow soldering, resistant to rework;
Comprehensive equipment management and maintenance and process control;
Strict WIP inspection and monitoring as well as working instruction;
Small quantity order is accepted;
12 hours quotation;
Prototype PCB capability;
Volume Production capability;


Application
Thin-film switch, Capacitive touch screen / panel,FFC for industrial control equipment,
Industrial control touch remote control soft board, Tablet PC camera soft board, Tablet
Computer battery soft board

FPC

Inner layer brown oxidation