Project: High-Density Flexible PCB Interconnect

Event: University of Toronto Aerospace Team (UTAT) – 3U CubeSat

Result: Successful Fabrication of Flex PCB and Breakout Prototypes

Objective: The mission required interfacing a FLIR TAU thermal camera payload with a remote receiver board at a ~70MHz data rate. The camera utilized a 20-mil pitch, 50-pin board-to-board connector, necessitating a high-density routing solution that could adapt to the satellite's evolving mechanical form factor.

Project Description: To bridge the physical gap between the sub-systems without compromising signal integrity, I designed a custom flexible printed circuit board using Altium Designer, allowing for controlled bending and spatial adaptability within the CubeSat chassis.

• Rigid-Flex Stack up Architecture: Utilizing Altium’s rigid-flex layer stack editor, I engineered a multi-stack-up board. The design incorporated polyimide (PI) base materials and FR4 stiffeners in targeted zones to enforce bend constraints, ensuring both mechanical durability and continuous data transmission across the flexible regions.

• High-Speed Routing & Fabrication: I implemented specialized layout practices for flexible routing to protect the 70MHz signals from degradation. The project also encompassed managing the specific DRC constraints of flexible circuits and generating the complex Gerber packages required for rigid-flex fabrication.

Outcome: The design phase concluded with the successful prototyping of a compact rectangular flex PCB and a dedicated breakout board. These prototypes enabled immediate sub-system testing and established a scalable interconnect architecture ready to be adapted to the satellite's finalized mechanical dimensions.