Important Disclaimer The project development described here represents the experience of 74ze Engineering's team members before the creation and incorporation of 74ze Engineering, Inc.

3.125 Gbps (XAUI) aTCA Backplane development with tested capability to be useful up to 5-6 Gbps

CLIENT

PICMG community of developers of telecom equipment.

CHALLENGE

Develop a high-speed backplane while working in a multi-vendor PCB environment and in an era with limited access to active test cards which were able to generate traffic at the required speeds. Solution must be low-cost (FR-4). Layer count was as many as 30 for an approximately 0.25" thick backplane.

SOLUTION

• AC (S-parameter) pessimistic simulations
• Implementation of wide traces to minimize skin effect losses
• Special techniques for x-talk minimization
• Careful avoidance of resonances
• Careful design of antipads in the high-speed connector area to minimize parasitic capacitance
• Built prototype for testing with 4-port VNA
• Correlation of simulated results to the VNA measurements (differential and common mode s-parameters)

BENEFIT

Backplane was successfully tested for speeds up to 5-6 Gbps.