Modern Components Powering Datacenter HPC Systems Amid AI Binge
Datacenter growth is soaring amid the expansion of cloud services and the sudden demand for artificial intelligence (AI) applications dependent on large language models (LLMs) that require greater scalability and vast computational resources. This requires a new generation of high-performance computing (HPC) systems utilizing specialized components that can address higher power and thermal management needs.
These datacenter needs are driving demand for enhanced passive components like power capacitors, resistors, and inductors that product designers can utilize in developing more advanced HPC devices to meet the requirements for AI processing. These requirements include greater efficiency, performance, reliability, and thermal management in smaller devices that enable datacenters to optimize space and increase the density of their systems.
Better inductors for HPC efficiency
KEMET, a subsidiary of YAGEO Group, developed metal composite inductors to improve the performance of DC-DC converters and switch-mode power supplies. Leveraging its history as a supplier of custom magnetic components to OEMs, it developed a standardized line of METCOM MPX power inductors that feature higher tolerance for current transients and higher operating temperatures, providing both compact design and high performance.
METCOM metal composite power inductors feature core high saturation flux density, which enables a stronger magnetic field than traditional ferrite inductors. They provide stable inductance across temperature and current.
The core consists of metal powder with an isolating coating and binding agent. The inductance range available for the MPX series is 0.1 to 100 µH.
Using round copper wire surrounded by a sintered magnetic metal composite powder (Figure 1) capable of stable inductance across temperature and current, the inductor construction makes it suitable for many DC-to-DC regulators such as switch-mode power supplies for datacenter servers, as power inductors, EMI filter inductors, and point-of-load regulators.
Figure 1: METCOM MPX power inductors use round copper wire surrounded by a sintered magnetic metal composite powder. (Image source: KEMET)
Metallic powder makes it possible to produce inductors with higher energy density and greater heat resistance, enabling smaller footprints than ferrite core inductors, along with the additional benefits of lower core losses at higher frequencies and superior suppression of electromagnetic interference (EMI). All of which combine to provide greater durability and reliability, which are essential to datacenter operations.
With more than 200 options in the MPX series (Figure 2), Kemet provides a wide range of choices. Dimensions available include 5 x 5 mm, 6 x 6 mm, 8 x 8 mm, 10 x 10 mm, 12 x 12 mm, 17 x 17 mm, and 22 x 22 mm.
Figure 2: METCOM MPX form factor. (Image source: KEMET)
The MPX1D0630L3R3, for example, is a 6 x 6 mm component with a height of 3.0 mm that allows for efficient use of space on a densely packed PCB without sacrificing performance. With a rated operating temperature up to +155°C, an inductance of 3.30 µH ±20%, and a maximum DC resistance of 30.3 mΩ, it is suited for HPC environments where maintaining power integrity, thermal management, and efficiency is critical.
For less rigorous requirements or greater versatility regarding inductance values, the MPX1D0530L220 comes in a 5 x 5 mm footprint with a height of 3.0 mm, with an inductance of 22.00 µH. With a higher maximum DC resistance of 341.2 mΩ, it would be suitable in cases where thermal management is less of an issue, or there is additional cooling built into the system.
Power bead inductor options for HPC
In HPC systems where general EMI suppression is required without stringent performance demands, another YAGEO company, Pulse Electronics, offers power bead inductors optimized for high current handling. They are designed specifically for use with trans-inductor voltage regulator (TLVR) topology.
Ferrite core power bead inductors are an alternative to the wound-toroid inductors that typically power desktop core voltage regulators (VCORE). Manufactured with through-hole technology (THT), power bead inductors deliver greater efficiency and offer tighter tolerances, allowing for smaller size in VCORE regulators.
Rather than staggering ripple currents of single-winding inductors in a multi-phase buck topology, the power bead inductors allow smaller inductances and enable a design tradeoff between how quickly the converter responds to a change in the load current (transient response) versus the stability of the control loop.
Pulse Electronics’ components are typically used in high-current, multi-phase voltage regulators that power processors, memory modules, and high-current ASICS and FPGAs for servers, graphics cards, storage, and datacenters. These dual-winding TLVR inductors are available in footprints ranging from 4 x 4 mm to 13 x 13 mm with inductance ranges from 20 nH to 1 µH.
Parts in the PAL6373.XXXHLT Series form factor (Figure 3), such as the PGL6380.101HLT, come in a 12 x 6 mm footprint with inductances ranging from 100 nH to 200 nH, saturation current ratings from 59 A to 125 A peak, and an operating temperature range of -40°C to +125°C. Constructed with a ferrite core assembled over a 1T or 2T winding, they feature extremely low DC resistance (DCR), high peak current, and low AC losses. They are available in single phase, integrated phases, and coupled inductor versions.
Figure 3: Pulse Electronics’ PAL6373.XXXHLT series power bead inductor form factor. (Image source: Pulse Electronics)
For HPC systems, the choice between power bead inductors and metallic composite types depends on the specific requirements of the system, such as the need for high inductance stability, temperature resistance, and noise reduction. The KEMET inductors offer stable performance over an extended temperature range, up to +180°C, and their molded metal structure helps reduce acoustic noise, which can be advantageous in noise-sensitive HPC systems.
Stable, long-life capacitors
Conductive polymer aluminum solid electrolytic capacitors from KEMET are also well-suited for the demanding requirements of HPC systems, where performance, efficiency, and reliability are critical.
Unlike traditional “wet” aluminum electrolytic capacitors that use conductive liquid electrolytes, the solid polymers in KEMET capacitors feature a low equivalent series resistance (ESR) that is stable across temperatures, frequencies, and operational lifetime.
Capable of higher ripple currents and longer life than wet capacitors, in which the electrolyte can dry and fail, solid polymer devices are more vibration resistant and designed for greater stability. They maintain capacitance effectively at high frequencies, making them an attractive option for fast-switching power supplies.
KEMET capacitors operate effectively under the high current demands typical in HPC systems without significant power loss, and they accommodate higher voltages compared to standard electrolytics due to the combination of conductive polymer and electrolyte. The improved electrical properties and robustness of polymer aluminum solid electrolytic capacitors can significantly enhance the overall efficiency and reliability of HPC systems compared to alternatives.
Designed to offer longer life and greater stability across a wide range of temperatures, KEMET’s A768 series of surface mount capacitors (Figure 4) come with values ranging from 18 µF to 1,200 µF, and in voltages ranging from 4 VDC to 80 VDC. For example, the A768MS108M1CLAE015 is a 16 V, 1000 µF version with an ESR rating of 15 mOhm and an operating temperature range of -55°C ~ +125°C. It has a landing pad size of 0.406″ L x 0.406″ W (10.30 mm x 10.30 mm).
Figure 4: A KEMET A768 series surface mount solid polymer aluminum capacitor. (Image source: KEMET)
These capacitors are designed to maintain performance in demanding thermal conditions, and versions are available to withstand vibrations up to 30 g for HPC environments where mechanical stress or movement could cause instability.
Thin film chip resistors
Another important component for HPC designs are chip resistors that complement power inverters and capacitors to protect against excessive current flow, and ensure a system’s overall stability and efficiency. In 2023, YAGEO Group introduced its NT Series of tantalum nitride thin film chip resistors, designed to maintain high consistency performance in demanding environments.
The self-passivation design of the NT series forms a waterproofing layer that shields the resistive layer to prevent moisture penetration. The devices are available in case sizes from 0402 to 1206, with a resistance range of 100 Ω to 481 kΩ.
With a wide operating temperature range of -55°C to +155°C, NT resistors contribute to stable power distribution and efficient energy transfer. They provide a low-temperature coefficient of resistance (TCR) of ±25, ±50 ppm/°C, with power ratings of 1/20 W to 2/5 W.
Conclusion
The demands of cloud computing and AI are driving the need for electronic components with specific attributes to provide high reliability under demanding conditions. Designers can meet the evolving requirements for HPC systems with specialized power inductors, resistors, and capacitors, such as those supplied by YAGEO Group and its KEMET and Pulse Electronics portfolio companies.