GBW and gm relationship of the subthreshold region Op-amp

[Junus2012]

Hello all

Kindly, I eould like to ask
how the transister working int the subthreshold region (weak inversion) has a high transconductance (gm) and hence high gain but small GBW.

if we have high gm then we must have GBW as (GBW = gm/Cc).

thank you

 

[erikl]

how the transister working int the subthreshold region (weak inversion) has a high transconductance (gm) and hence high gain but small GBW.

Transistor working in the subthreshold region (weak inversion) has a low transconductance (gm)! gm/Id is high.