Questions about the output of the Sigma-delta ADC, In Simulink, Plz help.

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Hi all,
In the process of designing Sigma-delta ADC, I come across some Q:

In sigma-delta ADC, it's conclude 2 parts: the modulator and the filters.
The output of the modulator is ±1, through the filter, its frequency is downsampled, However, the output is a sine wave (the input signal is a sine wave). My question is that : Now that the ADC is translate a analog input to a digital one, so the output of the Sigma-delta ADC should be a lot of digital signals, Such as 1111101111. not a sine wave.
By the way, Does the software limit this simulation ?
The output of the Sigma-delta ADC is in

 

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Hi, Thanks.
But in my simulation, the output is a sine wave, I guess the problem is the CIC filter, In CIC, these exist a data type conversion, How to set it ? I tried a lot of methods, But output is sine wave, not 011110

---------- Post added at 10:30 ---------- Previous post was at 10:23 ----------

The output of the Modulator is ±1, after through the CICfilter, the output becomes a sine wave.

 

[pancho_hideboo]

The output of the Modulator is ±1, after through the CICfilter, the output becomes a sine wave.

This is a very natural result.

But in my simulation, the output is a sine wave,

Again, this is a very natural result.

I guess the problem is the CIC filter,

No.

In CIC, these exist a data type conversion, How to set it ?
I tried a lot of methods, But output is sine wave, not 011110

Again, this is a very natural result.
Do you understand Delta-Sigma-ADC and CIC filter surely ?

Charactersitics of CIC filter is a moving averaging having sinc shape transfer function in frequency domain.

See the followings.
**broken link removed**
Understanding cascaded integrator-comb filters