Message - Message - 2025.2 English - UG906

Vivado Design Suite User Guide: Design Analysis and Closure Techniques (UG906)

Document_ID
UG906
Release_Date
2025-12-10
Version
2025.2 English

A user clock uncertainty of <delay> ns is defined on clock <clock_name> (see constraint position <position> in the Timing Constraint window in the Vivado IDE). High user clock uncertainty might adversely impact timing closure. Consider reviewing how much user clock uncertainty is required.