With the widespread application of AI technologies, the demand for AI power supply chips is experiencing explosive growth, from AI servers, accelerator cards to network switches. These chips not only provide stable power supply to AI systems to ensure their normal operation but also take the responsibility of energy conservation and emission reduction by lowering power consumption. However, with the increasing demand for computational power, issues such as energy consumption and heat dissipation in AI devices are becoming more prominent. Ensuring high-efficiency, low-power, and consistently stable power delivery has become a key focus for the AI industry.

The changes from traditional CPUs to GPUs as the core of computational devices has significantly improved processing efficiency, making complex data handling and deep learning models achievable. However, high performance often comes with high cost of power consumption. While pursuing faster computational speeds, the energy demand of GPUs continues to increase, imposing substantial energy pressure on data centers and servers. High-performance AI chips generate a considerable amount of heat during operation. If heat dissipation is not timely or effective, it can affect device stability, shorten their lifespan, and limit further growth in AI computational power. The thermal design power (TDP) of a single high-performance AI chip is expected to reach 1,000W, and in the future, more than 2,000W—reaching the upper limits of traditional air-cooling systems.

The requirements for power module density and size are becoming increasingly stringent. Taking the OAM (Open Accelerator Module) data processor as an example, the power demand for processors on a single board has reached 600W, far exceeding the output power of previous individual power modules. In the future, this demand may escalate to 1,000W or even 2,000W. Simultaneously, processor current requirements will increase from a few hundred Amperes to 1,000A or even 2,000A and above. As load power increases, customers demand higher efficiency from power modules, while the overall area of the unit on the board shrinks. Currently, efficiencies more than 95% have become standard spec. for such requirements. These conflicting demands pose a significant challenge for power module industry.

As transistor sizes shrink and their density increases, the coexistence of interconnect and power lines on circuit layers creates increasingly complex networks. With stacking layers rising to 10–20 layers, delivering power and data signals to the transistors has become a critical challenge. Consequently, the industry is researching solutions to move power lines to the back of the chip. This Backside Power Delivery Network (BSPDN) technology allows the chip front side to focus only on signal interconnects for transistors. It reduces congestion in the back-end wiring and offers power performance advantages, addressing the increasing power output challenges arising from transistor scaling.

Power module PCB Solutions

1. 2.5D Technology: Embedding components such as inductors, capacitors, resistors, and power devices into the PCB to reduce the overall product height and improve power density.

2. Controlled Depth Drilling Technology: Pre-machining controlled-depth grooves in the PCB based on phase requirements for assembling magnetic cores. During the assembly process, magnetic cores and components are integrated with the PCB in 3D, reducing size and increasing power density to meet high-current and high-heat dissipation demands.

3. Ultra-Thick Copper Technology: Current requirements include hole copper plating thickness ranging from 200μm to 500μm, with potential demand for even thicker copper in the future. Replacing copper pillars with plated copper achieves high-current capacity.

4. Laser Slotting Technology: By increasing the connection area between adjacent power and ground layers, this process reduces thermal resistance, improving current flow and heat dissipation in power modules.

5. HDI Any Layer Interconnections Technology: Combining laser-drilled vias and mechanical buried vias with plated flat surfaces meets the high-current and heat dissipation requirements of power modules.