High-performance embedded computing is subject to two challenging conditions:
- Rapidly advancing silicon performance (and heat generation) in denser packages
- Challenging environmental conditions
To prevent excessive heat buildup in environments that require high reliability, Annapolis Micro Systems is acutely focused on thermal management for our COTS boards and systems.
Following are some of the cooling technologies Annapolis utilizes to deliver rugged, reliable, and un-throttled processing performance. All are specified by the open VITA 48 REDI (Ruggedized Enhanced Design Implementation) standard.
Air (Convection) Cooled – ANSI/VITA 48.1
Cooling air flows directly over the board.
Typical Capability: 200 W per 6U slot
Best Application: Where shock, vibration, and air contaminants are not an issue
Board Example: WILDSTAR UltraKVP ZP 3PE for 6U OpenVPX (WB6XZ3) has an operating temperature of –40˚C to +70˚C
Chassis Example: WILD100 16-Slot Rackmount Beamformer Chassis (WC6C40) has an operating temperature of 0 to +55˚C
Conduction Cooled – ANSI/VITA 48.2
Utilizing a sealed enclosure, allows heat to conduct through a conduction plate on the module. Expanding wedge locks transfer the heat out to the chassis through wide slots cut into the metal chassis sidewalls. Lower junction temperatures increase the Mean Time Between Failure (MTBF).
Typical Capability: 150 W per 6U slot with air-cooled chassis (more with liquid-cooled)
Best Application: Rugged deployments requiring shock/vibe resistance, and where dust or other contaminants make it impossible to use blown air
Board Example: WILDSTAR 3XB1 3U OpenVPX FPGA Processor (WB3XB1) has an operating temperature of –55˚C to +85˚C
Chassis Example: WILD40 Forced-Air, Conduction-Cooled 3U OpenVPX Chassis has an operating temperature of –40˚C to +70˚C
Air Flow Through (AFT) – ANSI/VITA 48.8
Air is directed through an internal heat exchanger without contacting electronic components and connectors. Each AFT module has an isolated thermal path – its own inlet and exhaust. Seal design provides ability to use orifices which flow balance a chassis, channeling more air to modules that need higher flow rates. Also, AFT provides a weight reduction and cost savings by replacing wedge retainers and levers with lightweight jack screws.
Typical Capability: 200 W per 6U slot
Best Application: Rugged deployments where conduction cooling is not sufficient to meet system requirements
Board Example: WILDSTAR 3XB0 3U OpenVPX FPGA Processor (WB3XB0) has an operating temperature of –55˚C to +85˚C
Liquid Flow Through (LFT) – ANSI/VITA 48.4
This standard was ratified in July 2018. VPX plug-in LFT modules use liquid flowing through an integral heatsink of the module for cooling the circuit board. Quick disconnect coupling assemblies allow fluidic coupling to the chassis coolant manifold.
Typical Capability: 200+ W per 6U slot
Best Application: Rugged deployments where AFT cooling is not sufficient to meet system requirements