APAR LRU Brick Mechanical Design EOL APAR Team (Jim Ranson – EOL Design and Fabrication Services presenting) EOL APAR Advisory Panel March 2015

LRU Brick Mechanical CAD Model

LRU PCB Mechanical Outline Drawing

LRU Brick PCB assembly features LRU Module has integral Wedgelok® retainers for module retention in card cage, for blind-mate RF connector guiding, and for conduction heat transfer LRU Module has integral mount/heat sink Note: SMP board mount connectors are soldered and epoxy bonded to PCB for mechanical strength Power, Data/Signal, Programming, and Test connectors

SMP Blind Mate RF connectors SMP Blind-Mate Connectors: Low insertion loss 0 – 18 GHz frequency range Used for High-Density modular packaging Allows for radial and axial misalignment Used for phased array radar and active antenna applications

LRU Brick Modules assembled into card cage LRU Module #1 Card cage for 8 LRU’s Interface connector plate Antenna patch panel Cooling fans Card guides with Wedge-lok PCB retainers LRU Modules have RF shields/covers

APAR LRU Brick Thermal Design LRU Module PCB incorporates ground plane(thermal also) into Layer 11 (AGND) LRU Module PCB incorporates filled vias for heat transfer LRU Module PCB is in thermal contact with integral mount/heat sink through compliant thermal pad to insure waste heat transfers into heat sink (avoids air gaps) Estimate of LRU Module heat dissipation is 27 Watts per module. Initial thermal analysis estimates 50 CFM cooling air is required to dissipate waste heat for 8 LRU Modules. Cooling fans chosen are rated at 111 CFM. Design provides margin to account for air pressure drop and operation above sea-level conditions. Secondary cooling via conduction from integral mount/heat sink thru Wedge-loks into card cage. View showing finned heat sinks and fan positioning relative to LRU Modules

APAR LRU Brick assembly drawing