set_delay_model - 2023.2 English

Vivado Design Suite Tcl Command Reference Guide (UG835)

Document ID
Release Date
2023.2 English

Sets the interconnect delay model for timing analysis.


set_delay_model [‑interconnect <arg>] [‑quiet] [‑verbose]


Name Description
[-interconnect] Interconnect delay model used for timing analysis: Values: estimated, actual(default), none
[-quiet] Ignore command errors
[-verbose] Suspend message limits during command execution




Sets the interconnect delay model for timing analysis. There are three settings for the interconnect delay model: "actual", "estimated", or "none".

  • If "actual" is selected, the actual delay from the routed interconnect will be used in timing analysis. If the design is only partially routed, then the actual delay from the routed portion will be used, along with estimated delay for the unrouted portion. The timing report will provide details regarding the source of the calculated delay.
  • If "estimated" delays are selected, the timing analysis will include an estimate of the interconnect delays based on the placement and connectivity of the design onto the device prior to implementation. Estimated delay can be specified even if the design is fully routed.
  • If "none" is selected, then no interconnect delay is included in the timing analysis, and only the logic delay is applied.
Note: This command operates silently and does not return direct feedback of its operation.


-interconnect [ actual | estimated | none ] - (Optional) Delay model to be used. The default setting is actual.

-quiet - (Optional) Execute the command quietly, returning no messages from the command. The command also returns TCL_OK regardless of any errors encountered during execution.
Note: Any errors encountered on the command-line, while launching the command, will be returned. Only errors occurring inside the command will be trapped.
-verbose - (Optional) Temporarily override any message limits and return all messages from this command.
Note: Message limits can be defined with the set_msg_config command.


The following command will use a timing delay model which is an estimated value.

set_delay_model -interconnect estimated

See Also