sigma delta adc modelling

[liusupeng]

for simple first order sigma delta adc model, which one of the above is correct?
for (a), the transfer function is Y=X+(1-{Z}^{-1 } )Q.
and for (b), the transfer function is Y={Z}^{ -1}X+(1-{Z}^{-1 })Q.

---------- Post added at 09:05 ---------- Previous post was at 09:00 ----------


It is also interesting to note that both structures are used in second order sigma delta modelling.

 

[liusupeng]

anyone can help or it is too stupid to ask this?

 

[liusupeng]

some body.

 

[karim365]

a) like a delta modulator
b)sigma delta modulator

 

[liusupeng]

but for delta modulator, the signal transfer function should be high pass.

 

[liusupeng]

any suggestions

 

[liusupeng]

waiting

 

[liusupeng]

waiting

 

[liusupeng]

waiting

 

[liusupeng]

still waiting