Go inside proposals for common chiplet models

Chiplets have emerged as a powerful ‘more than Moore’ option for electronic systems. A recently published technical paper reviews part of the cross-industry work being done to develop standards and an ecosystem for their use.

Chiplets are an alternative to monolithic SoC design. They are discrete, unpackaged devices that perform specific tasks intended for aggregation into a single system using advanced 2.5D and 3D packaging technologies. They allow for performance scaling at lower cost than a monolithic approach.

Such heterogeneous design implies the likelihood that such systems will have multiple suppliers or, at least, design teams with their own discrete competences. Bringing chiplets together in the best way therefore requires a family of common machine-readable models.

To that end, the Chiplet Design Exchange (CDX), has been set up as a working group. It exists as part of the Open Domain-Specific Architecture (ODSA) sub-project within the Open Compute Project Foundation (OCP). CDX draws members from EDA, chiplet providers and end-users of system-in-package technologies.

CDX will soon publish a detailed white paper reviewing progress made so far on models and workflows. In the meantime, the new paper, ‘Proposed standardization of chiplet models for heterogeneous integration‘, summarizes the modeling chapter of that work.

It describes proposed models covering in the following areas:

• Thermal
• Physical
• Mechanical
• IO
• Behavioral
• Power
• Signal and power integrity
• Electrical properties
• Test

There is further discussion of  the documentation that can support chiplet integration within an electronic system and of the security traceability that will be needed in the supply chain for chiplets from multiple sources.

The authors are from ODX members Siemens EDA, Cameron EDA, Palo Alto Electron and Thrace Systems. Over-viewing the work in hand, they note that, “It is strongly recommended that these models are electronically readable for use in the design work flows. The models should leverage available, existing industry standards, with extensions and/or new standards defined as necessary.

“The initial scope of these proposed models is currently targeted for 2.5D interposer-based designs. Note that these 2.5D structures may include silicon interposers, silicon bridges, or organic based fan-out/RDL packaging
technologies, which can be referred to as ‘organic interposers’. Additional or modified deliverables will
be required to address the needs of 3D designs.”