在icc student workshop guide 可以经常看到的关于设置library问题上说:
The standard cell libraries have operating condition models,with PVT values that are equal to their respective library's characterized or nominal PVT values.
The macro cell libraries do not have any operating condition models, but their nominal PVTs match the nominal PVTs of their corresponding standard cell libraries.
这句话应该怎么理解呢?
字面意思都懂,但为什么没有这个operating condition models呢?