body effect design doubt analog

[gaurav5277]

Hello All,

what is the difference between these two conditions:

1. the bulk and source of a nmos is connected together and both are grounded (assume a current sink nmos)
2. the bulk and source of a nmos is connected together and both are at some positive potential(assume a cascode nmos ).

i wanted to know that will the threshold voltage be the same in both cases which would mean that in both these cases the device is undergoing same amount of body effect?

 

[fire_bolt]

Hi gaurav5277,

Yes:thumbsup:. Both will have same Vth and but no body effect since Vsb of each nmos device is zero.