PCB News - PCB design miscellaneous talk

Today, when the Turn-Key model is popular, chip manufacturers are doing a lot of the work of previous hardware engineers in advance. Now PCB design should be regarded as the hardware design of the entire system, where hardware engineers participate the most, spend the longest time, and make the most original part. As the carrier of hardware, PCB board is becoming more and more important. Generally speaking, it is the largest "component" in the entire system and the only truly custom-designed "component". At the same time, it is also a hardware design. One area that confuses hardware engineers the most.

There are actually many issues that hardware engineers need to consider when doing PCB design, such as signal quality, power integrity, EMC certification, high-speed design, DFM, and so on. And if your PCB designis good, these problems will be solved.

In addition to a good chip layout, a good PCB design another important PCB trace design. Regarding wiring issues, engineers generally refer to some design manuals. The design manual will generally tell you: the line cannot appear at any angle, 45° and 135° are the standards; when two lines of the same network cross, do not cross at right angles and acute angles, use 45° and 135° lines Transition; when a line crosses a right angle, you should never go at an acute angle, you can go at a right angle. In high-frequency design, there are special precautions, such as: high-frequency signal routing should avoid 90° bends, smooth arcs or 45° angles should be used, and high-frequency routing should reduce the use of via connections; All signal traces are far away from the crystal oscillator circuit; a single continuous trace should be used for high-frequency signal traces to avoid the situation that several sections of traces extend from one point.

The wiring angles are right angles, corners and arcs, whichever is better. How big a difference. For example, the problem of arc routing. Now many domestic customers require arc routing. After our test, we found that in fact, arc routing above 10GHz is helpful for system design, but below 10GHz, arc routing The line doesn't help much.