PCBA Tech - Common sense of Shenzhen pcba integrated circuit testing

Common sense of Shenzhen PCBA integrated circuit testing

1. Understand the working principle of integrated circuits and related circuits before testing
Before inspecting and repairing integrated circuits, Shenzhen PCBA processing process must first be familiar with the functions of the integrated circuit used, internal circuits, main electrical parameters, the role of each pin, and the working principle of the circuit composed of the normal voltage, waveform and peripheral components of the pin. If the above conditions are met, analysis and inspection will be much easier.
Precautions for designing high-speed circuit boards. Shenzhen PCBA processing process. I recently wrote a letter about an article on PCB characteristic impedance. This article explains how changes in the process cause the actual impedance to change, and how to use accurate field solvers to predict this phenomenon. I pointed out in the letter that even if there is no process change, other factors will cause the actual impedance to be very different. In the design of high-speed circuit boards.
1. Purpose
Used to evaluate the quality of electroplated holes and to evaluate the metallographic section of the surface, hole walls and covering layers of the circuit board. It can also be used in assembly or other areas
2. Test sample

Cut a sample from the circuit board or the test mold. A blank area should be left around the sample inspection area to avoid damage to the inspection area. It is recommended that each sample
Microscopic analysis is to evaluate the thickness of the coating, stress, dispersion, internal connection of multilayer boards, side corrosion caused by etching, drilling quality and solderability, etc. Microscopic analysis is an important part of PCB plating process control. According to the microscopic analysis, the typical process of printed circuit board (PCB) processing adopts the "pattern plating method". That is, pre-plated a layer of lead-tin anti-corrosion layer on the part of the copper foil that needs to be retained on the outer layer of the board, that is, the pattern part of the circuit, and then chemically corrodes the remaining copper foil, which is called etching.
It should be noted that there are two layers of copper on the board at this time. In the outer layer etching process, only one layer of copper must be on the automated assembly line. If the printed board is not flat, it will cause inaccurate positioning and components cannot be inserted. Mounted on the holes and surface mount pads of the board, it may even damage the automatic insertion machine. Shenzhen PCBA processing process. The board with the components is bent after welding, and the component feet are difficult to cut neatly. iPCB is happy to be your business partner. Our business goal is to become the most professional prototyping PCB manufacturer in the world. With more than ten years of experience in this field, we are committed to meeting the needs of customers from different industries in terms of quality, delivery, cost-effectiveness and any other demanding requirements. As one of the most experienced PCB manufacturers and SMT assemblers in China, we are proud to be your best business partner and good friend in all aspects of your PCB needs. We strive to make your research and development work easy and worry-free.
quality assurance
iPCB has passed ISO9001:2008, ISO14001, UL, CQC and other quality management system certifications, produces standardized and qualified PCB products, masters complex process technology, and uses professional equipment such as AOI and Flying Probe to control production and X-ray inspection machines. Finally, we will use double FQC inspection of appearance to ensure shipment under IPC II standard or IPC III standard.