Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

What's the difference between running the DC in normal vs the topographical mode?

Status
Not open for further replies.
S

surpriya.7

Newbie level 4
Joined
Jul 1, 2008
Messages
7
Helped
1
Reputation
2
Reaction score
1
Trophy points
1,283
Activity points
1,325
I'm trying to learn more about the topo mode with Design Compiler.
And other than few additional commands that the topo mode has, I couldnt tell the difference.

Thanks for any clues on this.
S
 

The main idea of topological synthesis is to have a more accurate wire length (cap and res) instead using wire load model.
 
Hi RCA,

I appreciate the response.
But doesnt dc_shell use the same wire load models, and loads the same libraries (fast, slow, tt libs for best, worst, tt cases) for the estimations?
Although, I would like to know more about how these estimations are more precisely done in topo mode?

I was only under the impression that its just the GUI shell (design_vision) that seperates the topo mode from the normal one.
But I'm feeling there is more to it.


Thanks
S
 

Simple DC uses WireLoadModel from the .db file. DC Topo takes as an input floorplan (from DEF file or from Milkyway) and TLU files (that keeps info for accurate RC calculation). Than it performs synthesis (as DC does), but also it performs coarse placement, in order to estimate distance between cells, and calculate real RC from this distance and TLU files. So, DC performs only synthesis based on WLM, DC topo performs synthesis+placement based on TLU files.
 
Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top