The difference between high-order HDI circuit boards and ordinary circuit boards in terms of signal integrity is mainly reflected in micro-pipe technology, line width and line spacing refinement, and high pad density. The specific introduction is as follows:
1. Micro-pipe technology:
High-order HDI circuit boards: use micro-pipe technology, especially blind and buried hole design, the diameter of these micro-holes is usually less than 150um. This design allows the HDI board to maintain high-density wiring while effectively reducing the size and weight of the circuit board, thereby optimizing the signal transmission path and quality.
Ordinary PCB circuit boards: usually use larger through holes, which limits the layout density of lines and components, may lead to longer signal paths, and increase the possibility of signal attenuation and interference.
2. Line width and line spacing refinement:
High-order HDI circuit boards: Line width and line spacing can be extremely fine, usually not exceeding 76.2um. This refined wiring helps to reduce electromagnetic interference and signal crosstalk, and improve the stability and accuracy of signal transmission.
Ordinary PCB circuit board: Due to technical and cost limitations, the line width and spacing of ordinary PCB are wider, which may lead to higher resistance and capacitance effects, affecting the integrity of the signal, especially in high-frequency applications.
3. High pad density:
High-order HDI circuit board: The pad density is high, with more than 50 contacts per square centimeter. This high-density layout not only supports more interconnections, but also improves the integrity and reliability of the signal through better interlayer alignment and thinner dielectric layers.
Ordinary PCB circuit board: The pad density is low, resulting in fewer connection points that can be accommodated in the same area, which may affect the overall performance of the circuit and signal transmission efficiency.
In summary, it can be seen that high-order HDI circuit boards have obvious advantages in signal integrity. These advantages are not only in the optimization of their physical structure, but also in the high-precision requirements for materials and processes, which enable them to perform well in high-speed and high-frequency applications. Although ordinary PCBs may have advantages in cost and manufacturing complexity, they may not meet the strict requirements for signal integrity in application scenarios with high performance requirements.
