Creating Asynchronous Clock Groups - Creating Asynchronous Clock Groups - 2026.1 English

Creating Asynchronous Clock Groups - Creating Asynchronous Clock Groups - 2026.1 English - UG903

Vivado Design Suite User Guide: Using Constraints (UG903)

Document ID

UG903

Release Date

2026-07-01

Version

2026.1 English

Use the -asynchronous option to create asynchronous groups.

set_clock_groups -name async_clk0_clk1 -asynchronous -group {clk0 usrclk itfclk} \
-group {clk1 gtclkrx gtclktx}

If you cannot predict the generated clock names, use get_clocks -include_generated_clocks to retrieve them dynamically. This option is an SDC extension.

set_clock_groups -name async_clk0_clk1 -asynchronous \
-group [get_clocks -include_generated_clocks clk0] \
-group [get_clocks -include_generated_clocks clk1]