Delta delay concerns nets that are switching. Noise analysis concerns nets that are not: a quiet victim next to a switching aggressor receives a pulse through the coupling capacitance. If the pulse is large enough and long enough, the receiving cell can respond to it as if it were a real transition. This topic covers how glitch height and width arise, how receivers are rated against them, why some receivers are far more dangerous than others, and the review process.
Lesson | After it you can... |
|---|---|
Compute the peak of a coupled glitch. | |
Compare a glitch with a receiver's tolerance curve. | |
Prioritise noise violations by receiver type. | |
Gate signoff on a noise summary. |
A delay change only moves a transition. A glitch can create a transition that should not exist, for example a spurious clock edge or reset, and corrupt state.