Hi,
I think that a "standard" 2nd order delta-sigma modulator has a NTF = (1-z
-1)
2. You get this transfer function by using two (delaying) integrators with transfer functions equal z
-1/(1-z
-1).
I don't really understand what's confusing you and I don't understand the transfer functions you gave (delay = z-1 ??)
Quote:TF = Z-1 / (1-Z-1), which contains a delay. Therefore it is different from standard model of 2nd order mod whose 1st stage integrator doesn't have delay (Z-1).
Probably I have to check the Berkley lecture notes first.
Regards