what is the differece between physical compiler and dc?

[dada1019]

what is the differece between physical compiler and dc?

 

[eda_wiz]

DC uses wireload model to calculate the fanout and other details of the design... which is less accurate..

PC uses better models(donno the name) to calculate the physical information.....

inessence.. physical compiler has more physical information about your circuit (wire delays, parasitic caps, IR drop etc) about the cells in the synthesis library ..and so it gives more accurate results. than DC

 

[Pulzar]

Physical compiler does placement and synthesis at the same time, while DC only does synthesis and estimates the wire lengths based on wireload models that you provide (which are usually based on module size).

Because physical compiler uses actual placement information to figure out the wireloads, the timing of your final design will closely resemble (as long as you don't later run into routing problems) what the physical compiler has produced. The netlist produced by DC, on the other hand, will probably need lots of massaging by the p&r tools to achieve the same timing results.

The downside, of course, is that DC runs a lot faster, because it doesn't case about cell placement.

 

[edavio]

DC is a pure synthesizor and PC can be a floorplaner. People can use pc after DC as well as using PC only.

 

[wadaye]

The output of DC is just netlist.

The output of PC is placed netlist.

You can get better result if you use PC because PC know the placed info

and no WLM is needed.

But you have give physical library(.pdb) and physical constrains((p)

def, .db) plus the file you give DC.

wang1

 

[justin999]

physical compiler will consider some layout place and route information

 

[gentle_man]

is the llibrary used by DC and PC same?

 

[wadaye]

is the llibrary used by DC and PC same?

DC need .db, PC need not only .db but also .pdb.

So PC need more than DC.

wang1

 

[yinhongtong]

what is the differece between physical compiler and dc?

Use LEF file and command "lef2plib" to convert LEF file to plib file .and then convert plib file to PDB file in PC.