Crosstalk delta-delay

Crosstalk delta-delay. A victim net transitions inside its switching window (the green band). Coupled aggressors can inject extra delay, but not every aggressor counts. Only the ones that meet both tests belong in the worst-case setup budget:

• Temporal alignment. The aggressor must switch inside the victim window. One whose window cannot overlap the transition injects nothing.
• Direction. It must switch the opposite way. Opposite switching roughly doubles the effective coupling capacitance (Miller effect) and slows the victim. A same-direction aggressor speeds the victim up, which eases setup, so it is left out of the setup budget.

Each contributor adds delta = k x Cc (its coupling capacitance sets the size). Click the aggressors that qualify. The budget is summed from their coupling caps and added to the arrival. Watch how a nominal slack that looks comfortable shrinks to the real margin once the aligned, opposite aggressors are counted. Select exactly the contributors, then Submit sign-off. (Hold is the mirror case: same-direction aligned aggressors are the risk there.)