How to change flip flop setup from positive value to negative

[kirangu]

Lets say we have a flop whose setup time is 10ns. How to convert this flop to the setup time of -10ns.

 

[yadavvlsi]

Add a buffer in the clock path that have have delay of 20ns. 10ns is huge??? Anyway why you wants -10ns setup?
Also see this https://www.edaboard.com/threads/7046/#17

 

[birdy123]

Hi,

As such the setup time of FF is defined in their respective library. If you want to cheange the characteristic of FF. then you can change there. But I dnt think that will help u ...

and as yadav asked -- why you want to do that?

 

[INS-ANI]

@Kirangu, it's not clear at which you want your setup time to be negative, at your flop input pin or package input pin.

In either way,if you delay your clock line you can get a negative setup time. However, if your flop gets a negative setup time at its input, it will not work. If you maintain a negative setup time at package input (depending on the package specifications) , your flop may work.
Actually the sole purpose of giving a negative setup time is to compensate for the delay acquired by the clock line with respect to the data line.

@others, please correct me if I am wrong.

 

[kirangu]

Thanks all for your valuable reply. This was the question asked form in an interview.