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Title
a

Anton Blanchard

03/05/2021, 11:23 AM
@User running DFFRAM through the OpenROAD flow shows up capacitance violations on the tristate buffer outputs. Experimentally, it seems we get into issues above 32 (it looks like DFFRAM is currently connecting 64). I looked in the liberty file and
max_capacitance/capacitance
for the Z pin is 33-39 depending on the gate size (wire capacitance would bring that down I presume). I'm not sure how much of an issue this is in practice. Would it just affect frequency, or are there other potential issues?