Set False Path Dialog Box (set_false_path)
set_false_path
Synopsys® Design Constraints (SDC) command described in the SDC
syntax reference. A variation of this command is available by
selecting a path in the Clock Transfers report and clicking
Set False Paths Between Clock
Domains.Allows you to define paths that the TimeQuest analyzer should
not analyze, such as test logic or any other path not relevant to
the circuit's operation. You can specify the source (-from), common
through elements (- thru), and
destination (-to) elements
of that path.
The following sections provide more information about specifying options for this constraint:
If you specify a clock as the collection for
the source (-from) element,
you must specify a clock for the collection in the destination
(-to) element.
Applying exceptions between clocks applies the exception from all
registers or ports clocked by the source (-from) clock to
all registers or ports clocked by the destination (-to) clock.
Applying exceptions between clocks is more efficient than applying
them for specific paths.
If you specify pin names or collections of
pins, the source (-from) element
must be a clock pin, and the destination (-to) value must
be any non-clock input pin to a register. Constraints from clock
pins, or to and from cells, apply to all registers in the cell or
those clocked by the clock pin.
From (-from):
Specifies the source (a collection Definition of clocks, registers, ports, pins, or cells in the design) in a path to which the timing constraint or exception applies. You can use the Name Finder to build a collection.
Through (-thru):
Specifies the common through elements ( collection Definition of pins or nets in the design) in a path to which the timing constraint or exception applies. You can use the Name Finder to build a collection.
-from) or destination (-to) elements.
To (-to):
Specifies the destination (a collection Definition of clocks, registers, ports, pins, or cells in the design) in a path to which the timing constraint or exception applies. You can use the Name Finder to build a collection.
SDC command:
Displays and allows you to enter SDC commands for the options you specify in this dialog box.