Clamshell Mode (DRAM Architecture)

What is Clamshell Mode?

Clamshell Mode is a DRAM configuration technique where two memory modules share the same memory channel but are mounted on opposite sides of the PCB (Printed Circuit Board). This layout is commonly used in systems requiring high memory density within constrained physical space, such as embedded systems, mobile devices, and automotive electronics.

Key Features & Benefits of Clamshell Mode

• Space Efficiency: In DRAM packaging, clamshell mode allows for higher memory capacity in the same physical space, which is ideal for servers and high-performance computing systems.
• Thermal Management: Distributing chips on both sides of the module can improve heat dissipation, especially when paired with advanced cooling solutions.
• Enhanced Performance: Higher density modules enable greater bandwidth and parallelism, supporting demanding workloads like AI inference and real-time data analytics.
• Cost Efficiency: Allows reuse of existing board designs while increasing memory capacity and performance.

Enabling Technologies

• SO-DIMM and UDIMM Modules: Clamshell packaging is often used in SO-DIMM (Small Outline DIMM) and UDIMM (Unbuffered DIMM) formats for compact and high-performance systems.
• DDR4/DDR5 Memory Standards: These standards support clamshell configurations to meet the growing demand for high-capacity memory modules.
• Thermal Interface Materials (TIMs): Used to manage heat between chips and heat spreaders in clamshell layouts.

Rambus Technologies in Clamshell Configurations

Rambus offers DDR5 memory interface IP optimized for high-density memory modules, including those using clamshell packaging. Their solutions support advanced signal integrity and power management features, making them ideal for data centers, automotive systems, and AI accelerators.