What do we do in pre-route STA and post-route STA in SOC encounter?

[cooldude040]

what do we do in pre route STA and Post route STA in SOC encounter ??

 

[shavakmm]

Re: STA

just to confirm that timing is still met ! routing add some more parasitic RCs....this may alter the timing ....!

 

[cooldude040]

Re: STA

How can routing alters the timing?? can u tell me?

Bcz it doesn't depend upon the parasitics i think am i right?
It depends upon the no. of buffers added , combi delays and so on
wt do u say?

 

[lakshman.ar]

STA

POST - routing ( a terminology similar to POST - layout i guess ) definately affects ur timing .... routing is the actual implementation of ur design ( hw its gonna come on the silicon) and hence the extact delays of the nets will be known only after that !!

during the pre-layout, the delays of the net is obtained frm wire-load models ( so u only get approxiomate timing closure values) , but only after placing & routing ur design, u get the real "net" values, so u hv to perform a "STA" after the routing as well !!!

parasitics extraction will be done only on the placed and routed netlist !!

so with this extracted values, u hv to perform a post-layout/route STA as well !!

WBR
Lakshman