What is multicycle path and false path?

[nemolee]

Dear Sir,

What is multicycle path ans false path?
How do I define constraint to these path?
Thanks.

 

[masai_mara]

A mutlicycle path is on where the generation of valid output takes more then one clock cycle. ex: pipelined FIR filter.
A false path is one where the data moves through different domains or where the transfer of data isnt affted by the clock period.

 

[no_mad]

Please read this:

 

[srik_naidu]

hi,
false paths are not related with clock and there is no effect on critical frequency due to these paths.

with regards,
srik.

 

[dolby.yang]

hi all:
false path shoud be the path that tell tool not to check timing about this path.

 

[nanako]

example of false path is the reset signal as usually you don't really do a clock tree on the reset signal, you just let it skew and it should affect the timing of your IC.

 

[jjww110]

false paths means tool need not to consider these paths.while multi cycle paths will take two or more clock cycles.

 

[tom123]

multicycle path are those paths that a operation will cost multiple clock cycles.

false path are those paths that the timing is not relavant.

Dear Sir,

What is multicycle path ans false path?
How do I define constraint to these path?
Thanks.

 

[rajavel]

Multi cycle path a timing path in which , between lanching edge and capturing edge it takes several cycles of the clock.
False path is a path which are not sensitised because of its logic configuration, operating mode with known constraints.

use set multi cycle path , reference clock and no. of cycles and set false patn commands in PT