2024-04-16

High density PCB boards have a rich history of development over the years. In order to describe the development history of high density PCB boards, we can divide it into different time periods.

In the 1950s, PCB boards were initially developed to replace the wire wrapping technique. At that time, the size of electronic components was relatively large, and the wiring density of PCB boards was not high. The total number of layers was only one or two, and the line width to spacing ratio was about 1:1.

In the 1960s and 1970s, the development of integrated circuits (ICs) significantly improved the performance of electronic devices. As a result, the demand for high-density PCB boards increased. At that time, IPC (Institute of Printed Circuits) and NEMA (National Electrical Manufacturers Association) jointly established the IPC standard. The line width to spacing ratio was reduced to 1:2 or even 1:3. They also introduced blind and buried via technology, which helped to improve the wiring density of PCB boards.

In the 1980s and 1990s, the size of electronic devices became smaller, and the integration density of ICs became higher. This led to the development of multilayer PCB boards. The number of layers increased to four to six, and the line width to spacing ratio was reduced to 1:4. In addition, SMT (Surface Mount Technology) was also widely used, which helped to increase the density of PCB boards further.

In the 21st century, with the development of modern technology such as mobile phones, laptops, and other electronic devices, the demand for high-density PCB boards has increased significantly. HDI (High-Density Interconnect) PCB boards have been developed to meet the requirements of these devices. HDI PCB boards can effectively reduce the area occupied by electronic components and increase the wiring density. The line width to spacing ratio has been reduced to 1:6, and the number of layers has been increased to 10 or even more.

In conclusion, the development of high-density PCB boards has gone through a long and constantly improving process. The evolution from single-layer PCB boards to multilayer PCB boards, and from rigid boards to flexible and rigid-flex PCB boards, has made tremendous contributions to the development of electronic devices. With the continuous development of technology, high-density PCB boards are expected to become even more widely used in the future.