The reason it does not depend on R3 and R4 is that we are more focussed on the charges to get the required VDD. Ultimately , the stored charges across capacitor gets you the voltage. So, the magnitude of R3 and R4 does not impact in any way on the charges to the C3 and C4.
27:24, maybe the first order approximation does not work for higher limits which can be confirmed by simulation. Sir is talking about the delay expression that we arrive by first order expressions right?
Professor is looking very cool !!
agree
The reason it does not depend on R3 and R4 is that we are more focussed on the charges to get the required VDD. Ultimately , the stored charges across capacitor gets you the voltage. So, the magnitude of R3 and R4 does not impact in any way on the charges to the C3 and C4.
Best Lecture Ever !! :)
27:24, maybe the first order approximation does not work for higher limits which can be confirmed by simulation. Sir is talking about the delay expression that we arrive by first order expressions right?
19:30 The capacitor voltage also the node voltage equation is not exact, it's approximate to a 1st order then?
Correct. It is a safe assumption that an RC model works in first order across all branches.
10::45_15-04-24_@IIIT-H
Why resistors R3 and R4 doesn't contribute for node 2 delay?
becoz we have to consider only those resistors which are common in path from src->destination node and src->current node