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My objective is to understand the difference between first and higher order Multi-bit sigma delta modulators in terms of DAC feedback signals.

I have a setup of 3-bit incremental sigma-delta modulator (first order system shown for simplicity, resetting not shown) as shown below: enter image description here

I was viewing the feedback DAC waveforms (after the DAC) between first and higher order modulators.

I noticed that the feedback DAC level is between any 2 levels for a first order modulator as shown below: (input voltage is 0.6 V) enter image description here

But for higher order modulators, the feedback waveforms oscillate between 2 or more levels as shown below: (input voltage is 0.6 V) enter image description here

I wanted to verify if this is something expected out of a higher order modulator and would this level switching would increase as modulator's order increases?

And this oscillation between more levels is responsible for high resolution? (in higher order Multi-bit sigma delta modulators)

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