Flexible PCB, abbreviated as FPC, is highly favored for its excellent characteristics such as light weight, thin thickness, and freedom to bend and fold. However, the quality inspection of FPC in China mainly relies on manual visual inspection, which is costly and inefficient. With the rapid development of the electronic industry, circuit board design is becoming more and more high-precision and high-density. Traditional manual inspection methods can no longer meet production needs, and FPC defect automation detection has become an inevitable trend in industrial development.
Flexible PCBs have excellent characteristics and broad market development space. Testing the quality, material, and performance of flexible PCB is beneficial for improving the manufacturing technology of flexible PCB and reducing material losses and environmental pollution. During testing, some necessary equipment is required, such as a high current spring micro needle module that can transmit current, which can establish a stable connection for flexible PCB testing.
1. Processes of flexible PCB
The process of FPC soft board includes exposure, PI etching, drilling, electrical testing, stamping, appearance inspection, performance testing, and so on. The production process of FPC is related to the performance of FPC. After production, testing is required to screen out unqualified FPC , ensuring that FPC maintains good performance in applications and plays the best role. In FPC testing, high current spring micro needle modules with conduction and connection functions can be used to ensure the stability and efficiency of FPC testing.
In the FPC process, exposure is achieved by transferring the circuit pattern to the board through the action of a dry film, usually using a photosensitive method. After exposure is completed, the circuit of the FPC is basically formed. The dry film can transfer the image and protect the circuit during the etching process. PI etching refers to that under certain temperature conditions, the etching solution is evenly sprayed onto the surface of copper foil through the nozzle, Redox occurs with copper, and then the line is formed after the film is removed. The purpose of opening holes is to form the original conductor circuit and the interconnection circuit between layers, and the opening process is commonly used for the conduction connection of the upper and lower layers of a double-layer FPC.
2. Basic testing standards of flexible PCB:
(1) Appearance of substrate film surface and covering layer;
(2) Deviation between the connecting disc and the covering layer, leakage of the adhesive and the covering layer, and discoloration of the conductor under the covering layer;
(3) Whether the temperature and humidity resistance, voltage resistance, bending resistance, and welding resistance meet the requirements;
(4) Poor electroplating bonding, coating leakage, etc.
During the voltage withstand test of FPC, the circuit needs to be connected to test its current transmission capacity and voltage bearing capacity. As a connection module, the high current spring micro needle module can transmit and conduct current within the range of 1-50A. It has strong overcurrent capacity and stable connectivity. The high current spring micro needle module after gold plating process not only has strong conductivity, but also has a reliable response method in the field of small pitch. It can adapt to pitch values between 0.15mm-0.4mm, has stable contact and does not get stuck in pins, and has an average service life of over 20w times. It does not need to be replaced frequently during testing, effectively saving time and material costs. The production difficulty of the high current spring micro needle module is low, the shipping time is fast, the service life is long, and the performance is stable. It can effectively improve the testing efficiency and increase the production of FPC in testing.
If you’re finding a supplier for yoour flexible PCB projects, contact us anytime.opcba.com will provide a one stop service for you.