for 1.2v bandgap referecne

[manissri]

i am working on 1.2v supply bandgap refernece.
for this i need to desing the error amp.
my query is that due to low voltage supply (1.2v)
can i put the input transistor in to subthreshold region.
cox its too tough to put the input trnsisor (single stage 5 transistor amp)
into saturation region. for making this transitor (input transistor) into saturation region i have to flow huge current in to the tail and due to this i can not get suffiecent gain
so wht will be effect on performance if puting input transistor into thr sub threshold region
regards

 

[leo_o2]

Model might not be accurate.

 

[elbadry]

I think to get a small overdrive you'd need a small current not a large one. You need a small overdrive in the input transistors so that the tail source doesn't go into triode region. Using NMOS, you might need to be in subthreshold. i think it's well-modeled in 0.13 and beyond.

Alternatively, you can use a PMOS input pair