Thank you Damian for pointing out such crucial mistakes
I have made a few changes and checked ‘normalization’ and then it gives a quantized output as shown in figure1. However with 3 bit resolution it only shows 5 levels instead of 8.
And without the normalize parameter checked, the ADC does not give any output maybe because of very low power output.
Also, you said that by keeping ADC parameter ‘sampling rate’ to default, we would get a quantized signal. Is there a way to get only sampled signal and not quantized ?