Double Sided Rigid-flex PCBs Built on Tg170 FR-4 and Polyimide With
Hot Air Soldering Green Solder Mask for POS Antennas
(FPC’s are custom-made products, the picture and parameters shown
are just for reference)
General description
This is a type of rigid flexible printed circuit boards for the
application of Wireless Security System. It’s a 3 layer rigid-flex
PCB at 1.6mm thick at rigid part. The base laminate is from
Shengyi. It’s fabricated per IPC 6012 Class 2 using supplied Gerber
data.
Parameter and data sheet
| Size of Flexible PCB | 91.5X 105.3mm |
| Number of Layers | 3 |
| Board Type | Rigid-flex PCB |
| Board Thickness | 1.6mm |
| Board Material | Polyimide (PI) 25µm |
| Board Material Supplier | Shengyi |
| Tg Value of Board Material | 60℃ |
|
| PTH Cu thickness | ≥20 µm |
| Inner Iayer Cu thicknes | 35 µm |
| Surface Cu thickness | 35 µm |
|
| Coverlay Colour | Yellow / Green Solder mask |
| Number of Coverlay | 2 |
| Thickness of Coverlay | 25 µm |
| Stiffener Material | NO |
| Stiffener Thickness | N/A |
|
| Type of Silkscreen Ink | IJR-4000 MW300 |
| Supplier of Silkscreen | TAIYO |
| Color of Silkscreen | White |
| Number of Silkscreen | 1 |
|
| Peeling test of Coverlay | No peelable |
| Legend Adhesion | 3M 90℃ No peeling after Min. 3 times test |
|
| Surface Finish | Immersion Gold |
| Thickness of Nickle/Gold | Au: 0.03µm(Min.); Ni 2-4µm |
| RoHS Required | Yes |
| Famability | 94-V0 |
|
| Thermal Shock Test | Pass, -25℃±125℃, 1000 cycles. |
| Thermal Stress | Pass, 300±5℃,10 seconds, 3 cycles. No delamination, no blistering. |
| Function | 100% Pass electrical test |
| Workmanship | Compliance with IPC-A-600H & IPC-6013C Class 2 |
Features and benefits
Excellent flexibility
Reducing the volume
Weight reduction
Increased reliability
The end can be whole soldered
Material optionality
Low cost
Continuity of processing
Professional and experienced engineers
Eligible products rate of first production: >95%
Applications
Laser head FPC, POS antenna soft board, tablet keypad flex board
Structure of FPC
According to the number of layers of conductive copper foil, FPC
can be divided into single layer circuit, double layer circuit,
multi-layer circuit, double sided and so on.
Single-layer structure: the flexible circuit of this structure is the simplest structure
of the flexible PCB. Usually the base material (dielectric
substrates) + transparent rubber(adhesive) + copper foil is a set
of purchased raw materials(semi-manufactures), the protective film
and transparent glue are another kind of bought raw material.
First, copper foil must be etched to obtain the required circuit,
and the protective film should be drilled to reveal the
corresponding pad. After cleaning, the two are combined by rolling.
Then the exposed part of the pad electroplated gold or tin to
protect. In this way, the big panel board will be ready. Generally
also it’s stamped into the corresponding shape of the small circuit
board. There is also no protective film directly on the copper
foil, but printed resistance soldering coating, so that the cost
will be lower, but the mechanical strength of the circuit board
will become worse. Unless the strength requirement is not high and
the price needs to be as low as possible, it is best to apply the
protective film method.
Double layer structure: when the circuit is too complex to be wired, or copper foil is
needed to shield the ground, it is necessary to choose a double
layer or even a multilayer. The most typical difference between a
multilayer and a single plate is the addition of a perforated
structure to connect the layers of copper foil. The first process
of transparent rubber + base material + copper foil is to make
holes. Drill holes in the base material and copper foil first,
clean and then plated with a certain thickness of copper. The
subsequent fabrication process is almost the same as the
single-layer circuit.
Double sided structure: both sides of the double sided FPC have pads, mainly used to
connect other circuit boards. Although it and monolayer structure
is similar, but the manufacturing process is very different. Its
raw material is copper foil, protective film and transparent glue.
The protective film should be drilled according to the position of
the pad first, then the copper foil should be affixed, the pad and
track lines should be etched and then the protective film of
another drilled hole should be affixed.
