VITA 93 – QMC: A modular leap forward for embedded defense systems
The Military Embedded Systems magazine shared our industry perspective on the emerging VITA 93 – QMC Standard. Learn more about our thoughts on how VITA 93 will be a strategic leap forward and what sets it apart. The article will also bring perspective on VITA 93’s position within a VPX-centric world and its integration within the broader VITA ecosystem.
The defense landscape is evolving rapidly – nowhere more visibly than in the skies over Ukraine. There, small, cost-effective drones have become indispensable tools for surveillance, targeting, and tactical disruption. This shift underscores a broader reality: embedded systems must now be smaller, more modular, and rapidly adaptable to new mission requirements. Platforms must be smaller, more modular, and rapidly upgradable. One powerful response to these demands is the emergence of the VITA 93 QMC standard that brings unprecedented modularity, flexibility, scalability, and ruggedness to system designers, making it highly relevant to modern defense and aerospace applications.
In mid-2025, the VITA 93 standard reached a critical milestone as the VITA Standards Organization (VSO) finalized the core mechanical and electrical specifications, and early adopters, including TEWS Technologies, announced their first modules and carriers in alignment with the new standard and first products are expected to be shipped in fall of this year. The announcement of the new standard raised a lot of interest in the market while the ecosystem continues to gain momentum. More product announcements from VITA member companies are expected in the near future.
The VITA 93 working group continues its work by drafting the VITA 93.1 substandard, defining QTM [QMC Transition Modules], small expansion mezzanine modules that will allow interchangeable connector interfaces on QMC carrier cards enabling even more flexibility and modularity.
A strategic leap forward
While mezzanine standards like PMC and XMC continue to play an important role in many embedded systems, evolving application demands – particularly those involving higher I/O density, greater thermal efficiency, and increased modular scalability – have driven the development of new approaches. VITA 93 was created to complement these existing standards by addressing emerging challenges in next-generation designs that require enhanced performance and flexibility across a broader range of platforms.
The VITA 93 standard introduces a modular, stackable mezzanine architecture that supports up to PCIe Gen 6 and allows configurations ranging from a single QMC (26 mm by 78.25 mm) to a quad QMC module (104.375 mm by 78.25 mm). This flexibility makes it a strong fit for systems requiring everything from basic serial I/O to complex, high-throughput sensor processing.
Moreover, VITA 93 is designed with interoperability at its core. A single QMC module can be installed on any compliant carrier regardless of stacking height, cooling method, or vendor. This level of abstraction not only simplifies integration but also promotes ecosystem development and competitive innovation – core goals of the modular open systems approach (MOSA) and related initiatives like the Sensor Open Systems Architecture, or SOSA, Technical Standard.
What sets VITA 93 apart?
Several technical innovations distinguish VITA 93 from prior mezzanine solutions:
- Scalable architecture: VITA 93 defines four module sizes – single, double, triple, and quad – each supporting a proportional increase in PCIe lanes and I/O pins. A single QMC module offers PCIe x4 and 40 I/Os, while a quad module scales to PCIe x16 and 160 I/Os. This approach enables system designers to choose the right footprint and bandwidth without needing to change carriers.
- Universal cooling design: A major pain point in prior standards was the mechanical incompatibility between air-cooled and conduction-cooled variants. VITA 93 solves this by using a unified mechanical layout. Designers can convert between cooling types simply by replacing the heatsink, with no PCB redesigns or additional variants needed. The conduction-cooling mechanism also offers superior thermal performance compared to legacy solutions.
- Flexible stacking heights: To support diverse mechanical envelopes, especially in VPX systems, VITA 93 carriers define four stacking heights – 9, 11, 14, and 16 mm – accommodating tight spaces and maximizing usable PCB [printed circuit board] area. This variable stacking height model enables designers to add components underneath the QMC, optimizing space without sacrificing performance.
- Simplified system integration: With standardization of interfaces and mechanical dimensions, QMC modules can be swapped across different platforms and carriers. System architects no longer need to coordinate tightly between I/O design and carrier layout, drastically reducing integration effort and time to market.
- Robust I/O organization: The 40 I/Os of a single QMC are organized into five IOPIPEs, each offering eight single-ended or four differential I/Os. Each IOPIPE comes with its individual ground supporting the integration of isolated interfaces. This setup also aligns well with military applications requiring discrete signal channels and galvanic isolation.
Scaling I/O in a VPX-centric world
VPX is a robust and proven platform, especially with 3U and 6U form factors aligned to the Sensor Open Systems Architecture, or SOSA, Technical Standard and the CMOSS architecture. System integrators face a recurring bottleneck, however: Each VPX slot is expensive, and traditional mezzanine cards like XMC can only offer limited flexibility due to its size; for example, a 3U VPX card can hold only one XMC.
Its smaller footprint enables multiple QMC modules on a single 3U VPX carrier, supporting multifunction processing without the need for multiple full-sized cards. As the military moves toward software-defined multifunction systems, this ability to pack heterogeneous I/O and compute onto one card becomes vital.
Moreover, the modular nature of VITA 93 aligns with the principles of MOSA, offering interoperability, vendor independence, and rapid upgradability – key demands for programs adhering to SOSA aligned procurement mandates.
Integration into the broader VITA ecosystem
VITA 93 does not exist in isolation – it’s a complementary addition to standards like VPX (VITA 46/48), VNX+ (VITA 90), and even external standards bodies such as PCI-SIG and PICMG. This interoperable nature ensures broad applicability in systems built on PCIe, CompactPCI Serial, and other small-form-factor platforms.
In a world where new threats emerge faster than procurement cycles, VITA 93 offers a new blueprint for agility. It meets the growing needs for flexibility, performance, and interoperability in a way that legacy standards simply cannot. Whether enabling scalable mission computing at the tactical edge or facilitating rapid system upgrades in airborne ISR [intelligence, surveillance, and reconnaissance] platforms, QMC is a timely and powerful addition to the modular embedded ecosystem.
QMC modules enable designers to add or swap new I/O capabilities at the module level without redesigning carriers or consuming precious slots. For defense contractors adapting rapidly to changing mission profiles, QMC delivers the time-to-market, cost, and SWaP advantages they need to remain competitive and mission-relevant. With ratification underway and productization accelerating, VITA 93 is not just a new standard – it is the future of mezzanine I/O.