PCB Tech - What are the PCB efficient wiring skills?

What are the PCB efficient wiring skills?

With the smaller and smaller PCB size and higher device density, although the current EDA tools are very powerful, the difficulty of PCB design is not small. As the most time-consuming part of PCB design, what are the efficient PCB wiring techniques?

1. Determine the number of layers of the PCB

  The size of the circuit board and the number of wiring layers need to be determined at the initial stage of the design. If the design requires the use of high-density ball grid array (BGA) components, the minimum number of wiring layers required for wiring these devices must be considered.

2. Design rules and restrictions

In order to complete the wiring task, the wiring tool needs to work under the correct rules and restrictions. Different signal lines have different wiring requirements. All signal lines with special requirements must be classified. Different design classifications are different. The rules involve the width of the printed lines, the maximum number of vias, the degree of parallelism, the mutual influence between the signal lines, and the limitation of layers. These rules have a great influence on the performance of the wiring tool.

3. Wiring in order

In order to achieve the best wiring of the printed board, the wiring sequence should be determined according to the sensitivity of various signal lines to crosstalk and the requirements of wire transmission delay. Generally, the wiring should be in the following order:

  A) Analog small signal line;

  B) Signal lines that are particularly sensitive to crosstalk;

  C) System clock signal line;

  D) Signal lines with high requirements for wire transmission delay;

  E) General signal line;

  F) Static potential line or other auxiliary lines.

4. Fan-out design

In the fan-out design stage, to enable automatic routing tools to connect component pins, each pin of the surface mount device should have at least one via, so that when more connections are needed, the circuit board can be internally layered Connection, online testing (ICT) and circuit reprocessing.

5. Manual wiring and processing of key signals

  No matter how powerful EDA tools are, manual wiring is an important process of printed circuit board design now and in the future. The use of manual wiring helps automatic wiring tools to complete the wiring work.

6. Automatic wiring

  For the wiring of key signals, it is necessary to consider controlling some electrical parameters during wiring. After understanding the input parameters of the automatic wiring tool and the influence of the input parameters on the wiring, the quality of the automatic wiring can be guaranteed to a certain extent.

The above is the efficient wiring skills of PCB manufacturers shared with you by the editor, I hope it will be helpful to you.