MicroTCA is a set of modular, open standards for building high-performance switched fabric computer systems. Centered aroundAdvanced Mezzanine Cards (AdvancedMCs or AMCs), the standard provides a low-cost, scalable platform for small-form-factor rack systems in applications like telecom, industrial control, and defense. First ratified in 2006 and most recently updated in 2024, hundreds of MicroTCA solutions are available from over a dozen companies worldwide.
On this Page
- Key Features and Benefits
- System Architecture
- Backplane Architecture
- Mechanical Design
- Power Distribution
- Related Documents
- MicroTCA® Products from our Members
Introduction to MicroTCA®
MicroTCA (µTCA) is designed to work in harmony with the Advanced Telecommunications Computing Architecture (AdvancedTCA) standards. MicroTCA systems are smaller and less expensive than AdvancedTCA systems, but their internal architectures are largely the same. Most notably, MicroTCA maintains full conformance with the AMC.0 module definition, enabling a wide variety of AdvancedMCs to be used within MicroTCA systems without customization.
MicroTCA was originally intended for smaller telecom systems at the edge of the network but has become popular in mobile, military, telemetry, data acquisition, and avionics applications. MicroTCA was Some of the advantages it offers these applications include:
- High Performance: Revision 3.0 of the MicroTCA.0 (µTCA.0) specification introduces 100 GbE and PCIe Gen 5 fabrics that improve backplane performance by 4x. The backplane bandwidth can be scaled to accommodate less-demanding applications and to adapt to future requirements.
- Low Cost: The architecture is consistent with Modular Open Systems Approach (MOSA) principles for reduced life cycle costs. It also minimizes initial investment, making it accessible for applications, including small-scale deployments and experiments.
- Modularity: Fully redundant and non-redundant systems including power budgeting and hot-swap configurations are supported. Components can be added, removed, or replaced with minimal disruption to the rest of the system, supporting ongoing maintenance and upgrades.
- Manageability: The standard Intelligent Platform Management Interface (IPMI) allows failure detection and isolation via enhanced hardware platform management. The standardized management protocols are compatible with AdvancedTCA, simplifying system management and interoperability.
- Compatibility: The architecture is designed for integration into standard rack systems, with support for both 19-inch and metric shelves.
System Architecture
The core specification, MTCA.0, defines the basic system, including backplane, card cage, cooling, power, and management. Subsidiary specifications (MTCA.1, MTCA.2, MTCA.3 and MTCA.4) define more ruggedized versions specifically suited for mil/aero and other demanding physical environments.
A minimum MicroTCA system includes at least one AdvancedMC, one MicroTCA Carrier Hub (MCH), and the necessary interconnect, power, cooling, and mechanical resources. A typical system can support up to twelve AdvancedMCs, optional redundancy for MCHs, Power Modules (PMs), and cooling subsystems, facilitated by a backplane and mechanical elements in a shelf.
Advanced Mezzanine Cards (AdvancedMCs): AdvancedMCs provide core functionality including processing, storage, and I/O, and are integrated directly into the backplane. MicroTCA supports six different sizes of AdvancedMCs.
MicroTCA supports six different sizes of AdvancedMCs.
Rear Transition Modules (RTMs): An RTM is an optional component that provides additional connectivity and interfaces that the front panel of the ACM may not support due to space limitations or the need for internal connections. This includes extra ports, storage interfaces, or other specialized features.
MicroTCA Carrier Hub (MCHs): The MCH performs the same functions as a Carrier Board within an AdvancedTCA system. It manages the AdvancedMCs and controls data flow within the system. A single MCH can support up to twelve AdvancedMCs, and redundant MCHs can be used to enhance reliability and availability.
Power Modules (PMs): PMs convert input power to the voltages required by the system components and distribute it. Options for redundancy and load sharing are provided.
Backplane: The backplane connects AdvancedMCs, MCHs, PMs, and other system components, facilitating data and power transfer within the system.
Monitoring and Control: A comprehensive management infrastructure based on IPMI standards enables monitoring, control, and management of system components.
Backplane Architecture
The backplane provides the physical and electrical connections between system components. It is designed to support high-speed data transfer and includes slots for AdvancedMCs, MCHs, and other modules.
The architecture uses differential high-speed SerDes serial links for data communication. These links support speeds of at least 3.125 Gbps in each direction. As of Revision 3.0, this enables support for 100 GbE and PCIe Gen 5 fabrics.
MicroTCA supports various fabric topologies, including star, dual star, and mesh, allowing for flexibility in system design. These topologies determine how data is routed between modules within the system.
The infrastructure supports multiple protocols for data communication, including PCI Express, Ethernet, and RapidIO, among others. This allows for the use of different types of AdvancedMCs within the same system.
In many configurations, the MCH includes a fabric switch that manages data routing between the AdvancedMCs. This switch can support different protocols and topologies, providing a central point for fabric management.
Mechanical Design
The architecture is designed for compatibility with 19-inch shelves, 19 as defined in IEC 60297M, as well as the Metric Shelf, as defined in IEC 60917 and ETS 300 119-4.
The foundation of the MicroTCA mechanical design is the Subrack, a structural framework that holds the modules and the backplane. The Subrack is equipped with card guides for aligning and securing the modules in place and is designed to accommodate different module sizes and configurations.
Shelves are larger enclosures that can house one or more Subracks and are designed to be compatible with standard equipment racks. They are engineered to support the weight of fully loaded Subracks, ensure adequate airflow for cooling, and allow for easy access to the components for maintenance.
MicroTCA supports flexible Shelf arrangements.
Cube and Pico Shelves are also specified for applications requiring smaller enclosures. These enclosures adhere to the same design principles as Shelves but are optimized for compact use cases.
Cooling may include fans, blowers, conduction cooling, and other mechanisms.
Power Distribution
The system can be powered by various sources, including AC mains (100V to 240V) or DC sources (typically –48V, –60V, or +24V). Power conversion modules transform the input power to the voltages required by the system, mainly 12V for payload power and 3.3V for management power.
Power is distributed through the backplane and dedicated connectors. This distribution is designed to be radial, allowing independent management and control of power to each component.
The architecture supports redundant power modules to enhance system reliability, allowing for N+1 redundancy configurations. Built-in protection mechanisms safeguard against overcurrent, overvoltage, short circuits, and other fault conditions, ensuring the reliability and longevity of the system components.
Related Documents
Family of Specifications
- Enhancements for MicroTCA.4
- Micro Telecommunications Computing Architecture Base Specification
- Air Cooled Rugged MicroTCA® Specification
- Hybrid Air/Conduction Cooled MicroTCA® Specification
- Hardened Conduction Cooled MicroTCA® Specification
- MicroTCA Enhancements for Rear I/O and Precision Timing Specification
