Design analysis of PCB power supply system

Today, it is difficult to successfully design high-speed electronic systems without a thorough understanding of the power supply system characteristics of the chip, package structure and PCB. In fact, in order to meet the requirements of lower supply voltages, faster signal flip-flops, higher integration, and many more challenging requirements, many companies at the forefront of electronic design have invested a lot of money, manpower, and resources in the analysis of power supply systems to ensure the integrity of power supplies and signals during the product design process.

Power supply system (PDS) analysis and design is becoming increasingly important in the field of high-speed circuit design, especially in the computer, semiconductor, communications, networking and consumer electronics industries. With the inevitable further isotropic shrinkage of ultra-large-scale integrated circuit technology, the supply voltage of integrated circuits will continue to decrease. As more and more manufacturers move from 130nm technology to 90nm technology, it is expected that the supply voltage will drop to 1.2V or even lower, while at the same time the current will increase significantly. From DC IR voltage drop to AC dynamic voltage fluctuation control, this development trend poses a great challenge to the design of power supply systems as the allowable noise range becomes smaller and smaller.

The design of PCB power supply system mainly involves the following aspects:

➤ Circuit design: according to the needs of the equipment, design a reasonable power supply circuit. This requires consideration of factors such as circuit stability, efficiency, safety and cost.

➤ Component selection: According to the circuit design, select appropriate components such as resistors, capacitors, inductors, etc. to meet the performance and cost requirements.

➤ Wiring Arrangement: Determine the layout and alignment of components on the circuit board to reduce the internal resistance of the power supply, avoid electromagnetic interference, and improve the reliability of the system.

➤ Heat dissipation design: Considering that the power supply generates heat during operation, it is necessary to design a reasonable heat dissipation scheme to ensure the stability and reliability of the power supply system.

Technical Challenges

In the design of PCB power supply system, the following technical challenges may be encountered:

▲ Circuit stability: The stability of the power supply circuit directly affects the performance of the entire device. Unstable or fluctuating power supply circuits may cause the device to malfunction or not work properly.

▲Component durability: Components in the power supply system may wear out or fail during operation. How to improve the durability and reliability of components is an important issue to be addressed in the design of the power supply system.

▲System anti-interference ability: power supply system in the working process, may be subject to electromagnetic interference from the outside world, how to improve the anti-interference ability of the system in the power supply design, is also an important technical challenge.

Solutions

In response to the above technical challenges, the following are some possible solutions:

〓 Circuit Design Optimisation: Adopt reasonable circuit topology and component layout to improve the stability and efficiency of the power system. For example, power supply circuits that require high stability, mature and stable power supply topologies such as LDOs (Low Noise Linear Regulators) or switching power supplies can be used.

〓 Component Quality Assurance: Select components with reliable and durable quality, and consider factors such as component tolerance and thermal characteristics in the design process. For example, grade X and Y resistors and capacitors are selected to meet the needs of high temperature, high humidity and harsh environments.

〓 wiring arrangement is reasonable: in the circuit board layout and alignment design, the power supply internal resistance and electromagnetic interference should be fully considered. For example, the main power line and ground line should be thickened to reduce internal resistance; at the same time, a reasonable signal line layout and filtering design should be adopted to reduce electromagnetic interference.

〓 heat dissipation design: according to the actual working condition, choose the appropriate heat dissipation scheme. For example, for power modules with large power, active heat dissipation methods such as heat sinks or fans can be used; for power chips with small power, natural heat dissipation can be used.

Conclusion

PCB power supply system design is an important part of electronic equipment. In the actual design, we must give full consideration to technical challenges such as circuit stability, component durability and system anti-interference ability, and improve the performance and reliability of the power supply system by optimizing circuit design, ensuring component quality, and rationally arranging wiring and heat dissipation design. In the future electronic equipment, with the continuous progress of technology and the continuous expansion of application scenarios, the design of PCB power supply systems will face more new challenges. Therefore, we need to constantly update our design concepts and methods to adapt to changing market demand and technology trends.