CTS : Global Skew Significance

[kumar_eee]

Why do we bother about the Global Skew? It doesn't help you in closing the timing, as local-skew does.

 

[rca]

Global skew was the first easy way to equilibrate the clock tree without considering the data path.
The local skew means you know which flop is linked to other flops.

 

[parkbench]

global skew gives you an idea about what sinks are pushing the clock insertion delay to increase. For example, if local skew skew is large for a certain skew group in test mode and it is causing hold problem, whether or not the global skew is large in func mode can explain why the local skew is large in test mode.

 

[kumar_eee]

Thanks rca & parkbench. Is it something to do with Test mode? I'm not finding any kind of explanations anywhere.