Double and triple Guard rings

[Amy25]

Hi all,

Can anybody please tell in detail why we use double and triple guard rings. I know why we use single gurad rings for preventing latch up and noise and how it works.But I am confused about the double guard rings and triple guard rings.

 

[leo_o2]

When the noise current is much bigger, double and triple guard ring is necessary

 

[erikl]

Staggered guard rings serve to better decrease noise impinging into (or escaping from) the surrounded area. It means trading noise immunity against real estate consumption.

 

[dick_freebird]

A shorted junction (double guard ring) sets up a local depletion
volume which will sweep out minority carriers entering it. A
single guardring only really provides a majority-carrier ohmic
tie and doesn't do much for loose minority carriers. Other
than providing a very small recombination center.

We used to use this scheme for fast recovery diodes and
switching transistor "base plugs", to push down the storage
time.

 

[Sidramareddy]

In simple way, the double guard will increases the protection....If the noise immunity is more then normal level, we will use higher guard ring levels like double guard ring....