European Classroom｜“Black Swan”: Is this the end of PCB boards?

Technology's black swans -- unexpected technological developments that change the course of the world -- will dominate. They put Glasgow in space race territory. The transistor and the Internet are obvious black swans, but there are less obvious ones, too: new materials and chemicals, cheap wireless communications, software that can simulate complex products before the parts are purchased and assembled. 3D printing gives everyone the chance to have their own personal mechanical prototyping lab for as little as $100. Extremely cheap GPS chips allow anyone to locate almost anything they wish.

Imagine another potential "technological black swan": the rise of an architecture based on power and data cables that could end the fate of the printed circuit board (PCB) in terms of value or utility. PCBs provide mechanical support and electrical connections for almost all electronic products. They use commonly used green materials to solder components and build intricate networks. But the disadvantages of PCBs are design limitations (it is a rigid flat board after all), it is difficult to work with other components, it is difficult to repair, it is expensive, and the signal strength decays rapidly with distance. PCBs have not changed much in many years; we just assume that it will always be this way.

Cable-based architectures free designers from the circuit board construction work that is at the heart of the product. Designers can completely ignore it and avoid a lot of problems. Power and data connectors can be "plugged" exactly where they are needed. Freed from the constraints of the PCB board, the maximum distance between connectors is greatly increased: the length between passive cables (that is, non-powered copper or optical cables) is extended by at least four times, and active cables (such as active optical cables) reach several kilometers. PCB requirements must adopt a coplanar structure, while cable connection structures can connect components in any direction, and the physical structure can be reduced or completely restructured. Architects can finally jump out of the usual cognition and reshape products without constraints. Imagine what this will do to the electronic devices that are inseparable from us all day long, such as smart textiles and other wearable devices, portable devices, etc.

In large electrical equipment, PCBs can severely impact cooling airflow. Airflow is blocked and turned back by the PCB, and thermal system engineers must design to eliminate these effects. But what if we removed this "wall"? Cable architecture has no "walls." Air and even water can flow freely throughout the equipment, which is more thermally efficient, resulting in lower energy consumption, lower operating costs, and even less impact on the global environment.

Cables are also generally more durable than PCBs and can maintain excellent signal performance in harsh environments with high temperatures that can easily cause PCBs to warp. Cables are often easier to service and repair: users don't have to unplug a circuit board with soldered components and intricate structures when a problem occurs. Imagine an architecture that uses only cables: all you have to do is unplug a component and replace it with a new one.