ywguo
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Hello,
As well known, nwell is often used as shield for PIP cap, MIM cap, or resisitors. But should the nwell shield be tied to vdd or gnd?
In Chapter 2, Analog Integrated Circuit Design, by David Johns and Ken Martin, it shows some examples that nwell shield is tied to ground.
From my point, I always tie the nwell shield to VDD to assure the p-n junction is reverse biased.
Who can analyze the two method for me?
Thanks in advance.
Yawei Guo
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