Author: Rick Nace, Chief Technology Engineer, LCR Embedded Systems

As the embedded electronic industry continues to embrace modular open architectures, thermal management must evolve alongside the electronics it supports. The adoption of open standards has fundamentally changed the way defense electronics are designed, integrated, and upgraded. Standards such as VPX, OpenVPX, and SOSA^TM were developed to address the longstanding difficulty of integrating hardware from different suppliers into a common system architecture. By defining standardized electrical and mechanical interfaces, these frameworks have enabled greater interoperability and reduced integration risk, creating a more adaptable future of technology across defense platforms. Thermal management is moving in a similar direction.

Thermal Management as a System-Level Requirement

Defense electronics have undergone a dramatic transformation over the past decade. Thermal management can no longer be treated as a downstream hardware consideration. Systems that once relied on relatively modest processing capabilities are now expected to support artificial intelligence, real-time sensor fusion, advanced radar processing, electronic warfare, autonomous operations, and high-speed communications all within increasingly compact platforms. While these advancements deliver significant operational advantages, they also generate substantially more heat.

While heat has always originated at the component level, today's embedded architectures generate more processing power, higher component densities, and faster interconnects within the same footprint. As a result, processors, GPUs, FPGAs, networking devices, power converters, and high-speed interfaces collectively contribute to a much more complex thermal environment, requiring cooling strategies that address the entire system rather than isolated components. As these systems become smaller, more powerful, and increasingly connected, the heat generated within compact enclosures can quickly compromise performance, reliability, and longevity.

Why VITA 100 Changes the Thermal Design Conversation

Just as standardized electrical and mechanical interfaces allow modules from different suppliers to work together, standardized thermal interfaces and cooling methodologies help ensure that heat can be transferred and managed consistently across the system. Standardized cooling strategies ensure alignment with the broader goals of modern electronic architectures: predictable interfaces, repeatable integration, and adaptable future technology insertion. VITA addresses these standard thermal interfaces and cooling methodologies in VITA 48.1, 48.2, 48.4, 48.5 and 48.8 for VPX architectures and is currently working on the new cooling technology approaches for VITA 100 (Next Gen VPX) architectures.

VITA 100 introduces significant advancements over previous VPX architectures, including increased connector density, expanded power capabilities, and support for technologies such as PCIe Gen 6 and 400G networking. As power densities continue to rise, thermal management must become a system-level design consideration that accounts for component selection, mechanical architecture, airflow paths, power delivery, and future technology insertion.

Cooling Technologies That Will Enable the VITA 100 Ecosystem

Enhanced interoperability and higher pin counts directly influence thermal management approaches. For example, the VITA 100 standard will double electrical connections and quadruple link bandwidth, driving increased compute densities that will break traditional cooling limits. To handle these higher thermal loads, system designers will need to transition to advanced cooling methodologies like Air-Flow-Through (AFT), Liquid-Flow-Through (LFT), or hybrid systems combining liquid chassis coldplates with conduction-cooled modules:

• Air-Flow-Through (AFT): Provides a scalable approach for managing increased heat loads while maintaining the modularity and serviceability associated with open architectures. By directing airflow through the module, it allows the cooling air to get closer to the heat generating components, lowering the thermal resistance when compared to traditional conduction cooled module implementations. This approach is well suited for systems where airflow infrastructure is available and where maintaining compatibility with modular plug-in architectures is a priority.

• Liquid-Flow-Through (LFT): Provides a greater thermal capacity for applications with extreme processing demands. By circulating liquid directly through the module’s heat frame, there is a reduction in thermal resistance since the liquid gets closer to the heat generating components. This is a thermal advantage when comparing to traditional liquid chassis coldplate implementations that rely on conduction cooling from the module to the chassis liquid coldplate. LFT can remove substantially higher heat loads than air-based methods.

• Hybrid cooling architectures: Combine multiple thermal management approaches to balance performance, flexibility, and system constraints. Hybrid approaches allow engineers to target the highest thermal loads while maintaining compatibility with existing mechanical and electrical architectures.

How to Approach the Future of Embedded Cooling 

As VITA 100 drives the next generation of embedded computing architectures, thermal management will become a critical factor in enabling higher performance, increased interoperability, and long-term system scalability. The development of the VITA 100 mechanical suite of standards, is helping define the approaches and mechanical requirements needed to support advanced cooling architectures.

Figure 1. The SAVE-compliant VE03 from LCR Embedded Systems delivers liquid-cooling performance to meet the extreme thermal demands of high-performance 3U VPX and SOSA aligned defense systems.

For example, the VITA 100.12 working group is working to develop a formal standard defining the requirements and interfaces for AFT plug-in modules, chassis, and backplanes. Once completed, this standard will define 3U, 4U, and 6U form factors to ensure mechanical compatibility, thermal performance, and interoperability within VITA 100-compliant systems. LCR is co-chairing this working group.

As the electronics industry continues to rapidly evolve toward smaller form factors and increased thermal densities, remaining at the forefront of innovation with new thermal management strategies is crucial for success. By integrating advanced thermal strategies into system design, engineers can enable the next generation of high-performance embedded platforms while maintaining reliability, scalability, and mission readiness.

Learn more about the future of cooling embedded systems in this blog by LCR.