Brief Introduction of FPC
Flexible Printed Circuit Board (FPC) is referred to as "soft board". In the industry, FPC is a printed circuit board made of flexible insulating substrate (mainly polyimide or polyester film), which has many advantages that rigid printed circuit boards do not have. For example, it can be freely bent, wound, folded. The volume of electronic products can be greatly reduced by using FPC, which is suitable for the development of electronic products in the direction of high density, miniaturization and high reliability. Therefore, FPC has been widely used in aerospace, military, mobile communication, laptop, computer peripherals, PDA, digital camera and other fields or products.
FPC also has the advantages of good heat dissipation, solderability, easy mounting and low cost.
Flexible printed circuit board has one layer, two layers and multilayer board. The base material is polyimide clad laminate. This kind of material has high heat resistance and good dimensional stability. It is the final product through pressing with the coating film which has both mechanical protection and good electrical insulation. The surface and inner conductors of double-sided and multi-layer printed circuit boards are metallized to realize the electrical connection of inner and outer layers.
The function of flexible circuit board can be divided into four kinds, namely, lead line, printed circuit, connector and multifunction integrated system, which cover computer, computer peripheral auxiliary system, consumer household electrical appliance and automobile, etc.
FPC Case: Multilayer Flexible PCBs Polyimide PCBs at 0.25mm Thick With Immersion Gold
(FPC’s are custom-made products, the picture and parameters shown are just for reference)
This is a type of a 4 layer flexible circuit for the application of Security Alarm at 0.25mm thick. The base laminate is from ITEQ, It’s fabricated per IPC 6012 Class 2 using supplied Gerber data. Polyimide as stiffener is applied on the inserting head.
Parameter and data sheet
|Size of Flexible PCB
|70.5 X 30.38mm
|Number of Layers
|Polyimide (PI) 25µm
|Board Material Supplier
|Tg Value of Board Material
|PTH Cu thickness
|Inner Iayer Cu thicknes
|Surface Cu thickness
|Number of Coverlay
|Thickness of Coverlay
|Type of Silkscreen Ink
|Supplier of Silkscreen
|Color of Silkscreen
|Number of Silkscreen
|Peeling test of Coverlay
|3M 90℃ No peeling after Min. 3 times test
|Thickness of Nickle/Gold
|Au: 0.03µm(Min.); Ni 2-4µm
|Thermal Shock Test
|Pass, -25℃±125℃, 1000 cycles.
|Pass, 300±5℃,10 seconds, 3 cycles. No delamination, no blistering.
|100% Pass electrical test
|Compliance with IPC-A-600H & IPC-6013C Class 2
Features and benefits
Reducing the volume
Consistency of assembly
Controllability of electrical parameter design
The end can be whole soldered
Continuity of processing
Supply small quantity, prototypes and production.
Meeting your printed circuit board needs from PCB prototyping to mass volume production.
Touch screen, industrial control touch remote control soft board, POS antenna soft board,
Bicheng has developed series of management procedures and approaches to assure that PCBs are in compliance with the customers' requirements, inclusive of selection of the vendors, work in progress (WIP) inspection, outgoing delivery inspection and customer service etc.
Evaluation and Audit of Suppliers
Suppliers have to be evaluated by Bicheng. In addition, Bicheng will appraise and rank suppliers every year to guarantee the materials supplied are meeting Bicheng’s requirements. Furthermore, Bicheng continuously develop suppliers and supervise them to improve their quality and environment management basing on the systems of ISO9001 & ISO14001.
Bicheng shall review and verify customer's requirements to make sure that we have the capability to satisfy customers' requirements including specifications, delivery and other demands prior to accepting an order.
Making, audit and control of manufacturing data.
When customers' design data and specifications are provided to our market department, Bicheng has to verify all the requirements. Then, convert the design data into manufacturing data by CAM. Finally, a manufacturing instruction (MI) is generated according to the real manufacturing process and technologies for manufacturing department as the basis for actual fabrication. MI must be reviewed by independent engineers and QA engineers before issue.
Incoming Material Quality Control
All materials have to be inspected before warehousing. We established a series of strict inspection procedure and instruction to control the incoming materials. Furthermore, various precise inspecting instruments and apparatus guarantee the capability to judge the material good or not. We issue material with first in first out principle, and give out “alarm” for the material that will reach the shelf life to ensure the materials are used up before expiry.
Control of Production Process
Right manufacturing instruction (MI), comprehensive equipment management and maintenance and process control, strict WIP inspection and monitoring as well as working instruction, all those make the whole fabrication process totally controlled.
Final Control and Inspection
All PCBs have to be gone through the open and short test as well as visual inspection after passed the specified physical tests. We own various advanced test equipment including customized, probe flying test machines to guarantee that each PCB is 100% tested.
Product Delivery Audit
We set up a dedicated FQA department to inspect the PCB products according to the customer's specifications and requirements by sampling. Qualified PCBs are going to be packed.
FQA also has to carry out a 100% audit of the warehouse packing and shipping products, including product number, customer number, product quantity, shipping address and so on prior to shipment.
We sets up a professional customer service team to proactively communicate with customers and timely deal with the customers' feedbacks. We highly focus on customers' needs and to understand customers’ demands, timely to adjust the policy of customer service and PCB product requirements.