moscap(decoupling cap between VDD and VSS has ESD issue?

[dennislau]

Due to larger capacitance per unit area, I put some moscap between power rail and ground for decoupling.

These moscap are very close to the ESD protection circuitry.

Are there any potential ESD issues?

During the ESD test, will the high voltage go into those mocap and damage it before the ESD protection circuitry start to function?

Thanks.

 

[dick_freebird]

That all depends on the qualities of your ESD clamps. Nobody can
tell you if your design is good enough to protect the MOS gate
or not.

But if it isn't then you will have problems everywhere, not just
the caps. Though caps present perhaps the largest single
target, with defect-induced weak spots to be ESD fail sites.

 

[dennislau]

Thanks very much.

Therefore, the first thing is to make sure a good quality of ESD circuit design. After that, the moscap should be placed properly so not to damage during ESD test.