Clock Domain Crossing Tools – Reviews & Metrics

A clock domain crossing (CDC) occurs when data is transferred from a flop driven by one clock to a flop driven by another asynchronous clock. Signals launched by a clock in one clock domain must be reliably captured by the clock in the second clock domain.

CDC sign off requires analysis, debug, modifications and verification that the data is properly transferred across clock domains, without introducing design problems.

There are special  clock domain crossing tools for sign off, as simulation and static timing analysis alone are not adequate.

Clock Domain Crossing Reviews

Below are user reviews on the best clock domain crossing tools from the annual EDA user report over the the past 3 years. The most recent report was released in early 2019.

CDC Product Metrics

Below are the primary metrics and criteria that the system and semiconductor verification engineers referenced when reviewing the products.

CDC Tool Metrics Covered

  • Sign-off methodology customizability
  • Noise level in CDC violation reporting
  • Debug usability, visibility and ¬†drilldown
  • Performance & Capacity
  • CDC analysis depth
  • Set up time

Multimode CDC Tool Metrics Covered

  • Sign-off quality, including fit with STA sign-off
  • Low noise
  • Common report with no duplicates to save CDC violation debug time
  • Modeling & constraining the design for complex clocking structures
  • Set up time & Capacity

Contributor: Gloria Nichols