Input Jitter - Input Jitter - 2026.1 English - UG903

Vivado Design Suite User Guide: Using Constraints (UG903)

Document ID
UG903
Release Date
2026-07-01
Version
2026.1 English

Input jitter is the difference between successive clock edges relative to ideal arrival times. Treat it as an absolute value that varies on either side of the edge. Use set_input_jitter to specify input jitter for each primary clock individually. You cannot set input jitter directly on a generated clock. The timing engine computes the jitter that a generated clock inherits from its master clock.

  • If an MMCM or PLL drives the generated clock, the engine replaces input jitter with computed discrete jitter.
  • If a combinational or sequential cell creates the generated clock, it inherits its master clock jitter.