UCIe Connectivity for 2.5D and 3D Multi-Die Designs

UCIe provides a common standard for die-to-die connectivity, but connecting dies in a 2.5D package is fundamentally different from connecting them in a 3D design.

In 2.5D designs, UCIe links traverse package channels where insertion loss, crosstalk, and increasing data rates influence PHY and package design. In 3D designs, shorter vertical connections and fine-pitch bonding allow bandwidth to scale through connection density, reducing the need for high-speed serialization, equalization, and channel training.

This white paper examines those differences and the engineering considerations behind choosing and implementing UCIe connectivity for advanced multi-die designs.

What you’ll learn:

• How UCIe connectivity differs across 2.5D and 3D designs 
• How F2B and F2F topologies affect interface design 
• How 3D integration changes implementation, test, and reliability requirements 
• How to align UCIe IP, package topology, and implementation strategy