moves it back to the launch edge at 0ns.

As a rule, a multicycle setup of N should be paired with a multicycle hold of N-1; otherwise the hold check is performed one cycle before the setup capture edge, which is usually infeasible. When the hold check edge and the launch edge are both at 0ns, the hold check does not depend on frequency at all.

KEY Hold is checked at the launch edge (0ns); pair a setup multicycle N with a hold multicycle N-1, and then hold is frequency-independent.

Timing Window

During timing analysis the tool records the earliest and latest switching times of each net. These two times bound the interval within a clock cycle during which the net may switch - that interval is the net's timing window.

STA uses the timing windows of aggressor nets to decide whether aggressors can switch together with a victim. The rising and falling switching windows provide the information needed to assess simultaneous switching for crosstalk analysis.

In short, a net's timing window is the span between its latest and earliest arrival times - the interval in which its signal may change within the clock cycle.

KEY A timing window is the interval between a net's earliest and latest switching times, used to judge aggressor co-switching for crosstalk.

Lower Frequency and Setup/Hold

• Setup timing improves for both full-cycle and half-cycle paths.
• Hold is unaffected on a full-cycle path because the launch and capture edges arrive together, but hold improves on a half-cycle path because the capture edge comes half a cycle before the launch edge.

KEY A longer period improves setup everywhere; hold is unchanged for full-cycle paths but improves for half-cycle paths.