Misleading description of mpw issues

[maliberty]

In slides/lec03.pdf page 13 it states STA tools did not calculat parasitics correctly. Would you explain on what you are basing this statement. It is not an accurate description of the MPW-1 failure to my knowledge.

[asinghani]

Hey Matt! That slide was based mostly off of this document that had been circulating when the issues were discovered, along with discussions I recall reading from the OSS silicon slack.

I'm interested to know if there's a more detailed / correct description of the issue as I'd very much like to update the slides if so.

[maliberty]

The statement STA tools did not calculate parasitics correctly doesn't match We were missing the correct values for parasitics for openSTA to work properly from the document. The former implies a tool error while the later is a user error.

My understanding is that they taped out using ideal clocks instead of propagated clocks.

[asinghani]

Ah good to know, will update in next semester's slides to be more accurate. These slides were intended to simplify things a bit since this is early in the semester (before students have much understanding of the subtleties of the different tools), but will make a note to clarify it. Thanks!