The appeal of 48 V technology: importance, benefits and key factors in system-level applications

Although a 48 V supply voltage can bring many advantages to system-level applications, we must also face some possible disadvantages of such a system.

Disadvantages to consider:

Component Compatibility and Availability

Switching to a 48 V supply voltage requires careful evaluation of existing system components, and some components may need to be replaced or adjusted. However, one potential problem is that there are not many components that are compatible with a given voltage rating. This can lead to higher purchase prices and delays in smooth system integration. Therefore, it is important to develop the right strategic planning and procurement approach. See Figure 7.

Design complexity

48 V supply voltage often leads to increased design complexity over a period of time. The implementation phase often requires careful handling of complex design issues, such as accurate voltage regulation, perfect thermal management strategies, and robust safety standards. Increased complexity may extend the development cycle and increase the need for specific technical skills. Therefore, companies need to assemble an experienced and capable design team to efficiently deal with these complex challenges.

Higher voltage-related risks

While 48 V is not particularly high, it can still present safety issues, especially if basic safety precautions are not adequately implemented. Increased voltage levels can increase the risk of electric shock and other hazards, so strict safety precautions must be taken.

Increased conversion losses

When voltage conversion is needed to power components that require lower voltage levels, such as sensors or low-power devices, the extra conversion step can result in increased energy losses in the system. This can offset some of the efficiency benefits of a 48 V supply voltage.

Traditional systems have limited adoption

For legacy systems targeting lower voltage levels, switching to a 48 V supply voltage requires careful evaluation. Subsequent adaptation efforts may face obstacles that make them both impractical and cost-prohibitive. Retrofitting existing infrastructure to smoothly support the 48 V standard can be a complex and time-consuming task, requiring significant adjustments and strategic planning to ensure compatibility and optimal performance.

Size and space limitations

While 48 V devices have lower current levels and can support higher power density, they may not be suitable for applications where size and space are critical. Additional insulation and safety precaution requirements may result in larger component sizes. See Figure 8.

Increased electromagnetic interference (EMI)

Increased voltage levels can also cause serious problems by increasing electromagnetic interference (EMI). Electromagnetic interference can prevent delicate components and complex communication networks from operating smoothly. Therefore, additional shielding techniques and high-standard filtering techniques are necessary to effectively offset and mitigate the negative effects of EMI and ensure that critical systems continue to operate reliably.

Scalability Challenges

While 48 V is a reasonable choice for many applications, some situations may be more favorable. Some applications, especially those at higher power levels, may require the use of other voltage designs to meet specific needs.

Cost considerations

Going to 48 V supply voltages requires careful consideration of upfront costs, including the cost of replacing components, coordinating system development, and implementing critical safety measures. These initial expenses can have a significant impact on the overall project budget, depending on the application and industry. In the face of these potential expenses, wisely allocating resources is critical to a smooth integration and success.

in conclusion

48 V supply voltage is no longer a niche option, but has become a key component in system-level, industrial and communication applications, meeting the growing demand for energy-saving solutions with higher efficiency, higher power density and greater design flexibility. However, the success of 48 V applications is inseparable from efficient power conversion, strict thermal management, robust safety precautions, standardized communication protocols and sophisticated monitoring and control systems. As the technological environment evolves, 48 ​​V supply voltage remains a key innovation driver in multiple fields and will continue to provide efficient and reliable power in the future.

Figure 7. Electrolytic capacitor capacitance decreases due to electrolyte drying up

Figure 8. Capacitor output side circuit installation precautions 8

Furthermore, in system-level applications, the 48 V supply voltage offers significant advantages that are worth investigating by the designer or application engineer. However, we must also fully weigh the trade-offs and fully understand the potential drawbacks that this choice may bring. In order to wisely use this voltage level for a specific application, component compatibility, design complexity, safety precautions, energy conversion losses, and related costs should be considered.

References

1 Brad Xiao and Nazzareno “Reno” Rossetti, “Dealing with the 48 V to 12 V Step-Down,” Power Electronics Tips, February 2021.

2 Christian Cruz, Gary Sapia, and Marvin Neil Cabueñas, “Smart Battery Backup for Uninterruptible Energy Part I: Electrical and Mechanical Design,” Analog Dialogue, Volume 57, Number 4, December 2023.

3 Anant Kamath, “Simplifying Isolated CAN Power Interface for HEV 48 V Systems,” Electronic Design, April 2019.

4 Glenn Charest, Steve Mills, and Loren Vorreiter, “Open Rack V3 Base Specification,” Open Compute Project, September 2022.

5 “Power Supplies for Telecommunication Systems,” Analog Devices, Inc., July 2002.

6 “48 V Step-Down Converter Helps MHEVs Meet Fuel Emission Standards,” Analog Devices, Inc., March 2020.

7 “Is it essential for data centers? Reasons for the need for 48 V power supply and related power supply design challenges,” Panasonic Industry, August 2021.

About the Author

Christian Cruz is an application development engineer at ADI Philippines. He holds a bachelor’s degree in electronics engineering from the University of the East in Manila, Philippines. He has over 12 years of engineering experience in analog and digital design, firmware design, and power electronics, including power management IC development, and AC-DC and DC-DC power conversion. He joined ADI in 2020 and is currently responsible for supporting the power management needs of cloud-based computing and system communication applications.