How to distinguish between good and bad circuit boards? Manufacturers know that making a PCB board is to turn a planned schematic into a real PCB circuit board. Don't underestimate this process. There are many things that work in principle but are difficult to complete in engineering, or things that others can do but others cannot. Therefore, making a PCB board is not difficult, but doing a good PCB board is not an easy task.

The two major challenges in the field of microelectronics lie in the processing of high-frequency signals and weak signals. In this regard, the level of PCB manufacturing is particularly important. With the same principle planning and the same components, PCBs manufactured by different people will have different results. So, how can we make a good PCB board? Based on our past experiences, I would like to share my views on the following aspects:

Clear planning goals are necessary

When faced with a planning mission, the first step is to clarify its planning objectives, whether it is a regular PCB board, high-frequency PCB board, small signal processing PCB board, or a PCB board that has both high-frequency and small signal processing. If it is a regular PCB board, as long as the layout and wiring are reasonable and neat, and the mechanical scale is accurate, it is sufficient. If there are medium load lines and long lines, certain measures should be taken to reduce the load. Long lines should strengthen the drive, and the key is to avoid long line reflection. When there are signal lines on the board that exceed 40MHz, special considerations need to be given to these signal lines, such as inter line crosstalk. If the frequency is higher, there will be stricter constraints on the length of the wiring. According to the network theory of dispersion parameters, the interaction between high-speed circuits and their connections is a decisive factor that cannot be ignored in system planning. With the advancement of gate transmission speed, the opposition on signal lines will correspondingly increase, and the crosstalk between adjacent signal lines will increase proportionally. Generally, the power consumption and heat dissipation of high-speed circuits are also high, which should be given sufficient attention when making high-speed PCBs.

How to distinguish between good and bad circuit boards?

When there are weak signals at the millivolt or even microvolt level on the board, special attention needs to be paid to these signal lines. Due to their small size, small signals are easily disturbed by other strong signals, and shielding measures are often necessary, otherwise the signal-to-noise ratio will be greatly reduced. So much so that useful signals are drowned out by noise and cannot be effectively extracted.

The debugging and testing of the board should also be considered during the planning stage. Factors such as the physical orientation of the testing points and the isolation of the testing points should not be neglected, as some small and high-frequency signals cannot be directly measured by adding probes.

In addition, other relevant factors should also be considered, such as the number of layers on the board, the packaging shape of the components used, and the mechanical strength of the board. Before making PCB boards, it is important to have a clear understanding of the planning objectives.

Article sourced from Jiangmen single and double-sided circuit boardhttp://www.yonghongpcb.com/