set_false_path & set_case_analysis

[jojo12520]

hi,all.
I'm a new comer.

I have a question:
What's the difference between set_false_path and set_case_analysis?

Thanks.

 

[sree205]

thats like comparing chalk and cheese.

set_false_path means that particular path will not be considered for timing analysis.

set_case_analysis is a way of tying a port or pin to a constant value of either 1 or 0.

 

[jojo12520]

sree：
does it mean they have no relationship or similarity in function? it is a write_test of cadence and i am confused.

thanks

 

[sree205]

to my knowledge these are design compiler commands and i've posted the descriptions of these commands. by write_test, if u mean generation of test patterns in dft_compiler, i'm not sure how these commands can be used there.

Also, for the list of variables which affect the write_test, please type write_test and press tab in ur dc shell prompt.

u can also check this link in the mean time.

**broken link removed**

 

[jojo12520]

thank u very much

 

[bhanupratap56]

what u people talking about?

 

[cffyh]

set_false_path means the path is exist,but we don't want to check it;
set_case_analysis will assign a constant value to a pin or port,and this value will will decide which arc(path) will be disabled!

 

[ljxpjpjljx]

set_false_path is the timing path which we don't care!
set_Case_analysis is the method we can set some value for a pin or a port!

 

[dftrtl]

set_case_analysis will make path to disappear
set_false_path will make existing path as false(will not be timed)