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Mouser Electronics White Paper Rising Temperatures The modern data center requires extensive data transmission and power connectivity infrastructure. However, the transmission and consumption of electrical energy create heat. As the workloads created by AI continue to grow, so will the heat they generate. High- density servers, GPU accelerators, and memory devices are all forcing designers to face thermal loads that traditional technologies are ill-equipped to handle. In this environment, connectors must play their part by minimizing their heat contribution and providing new and innovative approaches to thermal management. Heat generation is a function of the equation for power loss (P=I²R). Known as Joule's law, this equation shows that energy loss (P) is proportional to the resistance (R) of the circuit multiplied by the square of the current (I). This energy will be lost as heat, increasing the temperature of the cables and connectors carrying the power while also heating the environment around them. The Effects of Heat Heat is more than just an unwanted side effect of power delivery. It can significantly impact the operation of any data center and severely affect the long-term reliability of electronic systems. Thermal cycling can cause materials to expand and contract, leading to wear and degradation, especially in critical components like insulation on cables and connectors. Heat also affects semiconductor life cycles. A well-known rule, based on the Arrhenius equation model, states that for every 10°C rise above a device's optimal operating temperature, mean time between failures (MTBF) decreases by as much as 50 percent. These elevated temperatures also affect computational performance. Modern processors include thermal protection mechanisms, such as thermal throttling, which reduces clock speed when temperatures rise. This delay could be disastrous for any safety-critical application that relies on AI analysis. Conventional Thermal Management Thermal management is a familiar challenge for designers that has become even more critical with the high workload demands of the latest AI accelerators. Conventional air cooling—using fans and blowers to carry heat away from critical components—is an effective but expensive method of thermal management. Studies by the IEA suggest that as much as 40 percent of the energy consumption in modern data centers is devoted to cooling (Figure 4). 7 Figure 4: Cooling is one of the biggest engineering challenges for modern data centers. (Source: Maryna/stock.adobe.com) In the pursuit of data center infrastructure that reduces heat production, connectors can positively contribute to thermal management. Many of the connectors used in rack-based systems are linear, which have the potential to disrupt the free flow of air through servers. In some applications, it is possible to reorient connectors on printed circuit boards (PCBs) for better airflow. For other designs where this is not possible, the design of the connector itself can play a role. Amphenol Positronic's Scorpion power connector system addresses airflow needs with a modular design that lets users configure contact arrangements to better distribute thermal load across the connector. Equally important is the option to incorporate cavities along the connector to allow airflow through the insulator. This can help reduce the connector's temperature while allowing air to flow freely over the PCB. Even with these innovative features, the extreme thermal loads created by the latest chipsets challenge the effectiveness of air cooling. The low thermal capacity of air and the high energy costs created by large cooling systems have forced engineers to explore liquid cooling technologies. The higher thermal capacity of liquids makes them significantly more effective for cooling purposes. The Advantages of Liquid Cooling From our earliest experiences at school and home, we are taught that one should never mix liquids and electricity. Therefore, placing an entire printed circuit board into liquid can appear counterintuitive. However, non-conductive or dielectric liquids are entirely safe for use with electronic systems, and immersing a PCB in such a liquid provides uniform cooling without the need for fans. This technique not only reduces energy and maintenance costs but also contributes to a far quieter workspace. The efficiency of immersion cooling is complicated by the requirement for specialized enclosures. A key requirement of any data center

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