How to Determine DDR5 Controlled Trace Impedance

+ Electrical Performance Scan App

Adjusting memory-controlled impedance from ODB++ files

Addressing signal reflections in Double Data Rate 5 (DDR5) designs requires adjusting the memory interface-controlled impedance to match the driver impedance. DDR5 specification offers no explicit impedance recommendations, and vendor-suggested ranges require analytical validation to ensure compliance with standard specifications. Incorrectly defined impedance can lead to signal integrity issues that reduce overall system performance.

To eliminate reflections, designers evaluate physical parameters (trace width, dielectric thickness, and copper weight) to meet the desired controlled impedance. Designers can use ODB++ files and simulation software to electrically scan designs' performance and generate impedance reports and eye diagrams for the operating data rate. Simulation enables designers to assess different iterations efficiently to adjust the controlled impedance.

Impedance electrical performance scan solution

Determining the correct impedance for DDR5 traces requires properly designed traces with matching impedance. The Keysight impedance electrical performance scan solution (EP-Scan) generates automated reports for trace impedance, skew and delays, impedance maps, and eye diagrams for different data rates. It enables designers and hardware engineers to perform fast simulations and automated impedance analysis using layout geometry files without requiring advanced signal integrity knowledge.

Get quote