DFT Compiler error: Bus gate xxx failed Z state ability check

[LinXiaoling]

Hi,
during the DFT design, there comes a problem:Bus gate xxx failed Z state ability check. the cause may be the bidirectional ports in the design.but I don't know how to handle it.pls help me,thx.

 

[feel_on_on]

DFT Compiler problem

the Bus is a bidirectional ports?

or you can upload a example ,I will help you to solve it

 

[LinXiaoling]

Re: DFT Compiler problem

THX!
my design is the top design that including bidirectional IO pads.there exists pre-dft DRC warnings on those pads.

 

[santhosh007]

Re: DFT Compiler problem

make sure that the only one driver is driving the bidi IO during test mode. that will solve contention issue and stabiltiy check.
simple solution would be : gate bidi enable with test mode signal. whenever test mode is 1, it will be in output mode.