PCB Technical - PCB circuit board distinguish good from bad

With the rapid development of the mobile phone, electronics, and communication industries, it also promotes the continuous growth and rapid growth of the PCB industry. People have more and more requirements for the number of layers, weight, precision, materials, colors, and reliability of components. high.

However, due to fierce market price competition, the cost of PCB board materials is also on a rising trend, and more and more manufacturers are monopolizing the market with low prices in order to enhance their core competitiveness. However, behind these ultra-low prices are obtained by reducing material costs and process manufacturing costs, but devices are usually prone to cracks (cracks), scratches, (or scratches), and their precision, performance and other comprehensive factors have not reached the standard., Which seriously affects the solderability and reliability of the product.

Faced with a wide variety of PCB circuit boards on the market, there are two ways to distinguish the quality of PCB circuit boards; the first method is to judge from the appearance, and the other is to judge from the quality specifications of the PCB itself.

How to judge the quality of PCB circuit board

1. Identify the quality of the circuit board from the appearance

Under normal circumstances, the appearance of the PCB circuit board can be analyzed and judged through three aspects:

Standard rules for size and thickness: The thickness of the circuit board is different from that of the standard circuit board. Customers can measure and check the thickness and specifications of their own products.

Light and color: The external circuit board is covered with ink, and the circuit board can play the role of insulation. If the color of the board is not bright and less ink, the insulation board itself is not good.

Weld appearance: circuit boards have many parts. If the welding is not good, the parts are easy to fall off the circuit board, which will seriously affect the welding quality of the circuit board. It is very important to have a good appearance, careful identification and a strong interface.

2. High-quality PCB design needs to meet the following requirements

The phone is required to be easy to use after the components are installed, that is, the electrical connection must meet the requirements

The line width, line thickness, and line distance of the line meet the requirements to prevent the line from heating, breaking, and short-circuiting.

The copper skin is not easy to fall off under high temperature.

The copper surface is not easy to oxidize, which affects the installation speed, and it will be broken shortly after being oxidized.

There is no additional electromagnetic radiation.

The shape is not deformed, so as to avoid deformation of the housing and dislocation of the screw holes after installation. Now it is all mechanized installation, and the deviation of the hole position of the circuit board and the deformation of the circuit and the design should be within the allowable range.

High temperature, high humidity and resistance to special environments should also be considered.

The mechanical properties of the surface must meet the installation requirements.

The above is the way to judge the quality of PCB circuit board s. When buying PCB circuit boards, you must keep your eyes open.