vrs007
Member level 1
Am a bit new to using matlab for simulation of sigma delta ADCs...have a few doubts:
1)While calculating output power spectrum we take the FFT and plot only single sided spectrum...this is because the spectrum is symmetrical...but isnt the spectrum from -fs/2 to +fs/2??I have seen tht in most codes the 0 to fs interval is divided into N/2 points for a N-pt fft instead...so tht means the matlab fft function computes it from -fs to +fs...confusing for me...sorry if I have confused you
2)Doubt regd ENOB...what does it signify??when i simulate my ADC in simulink I get a sequence of +1 and -1(which are my quantization levels)...so when for example...it is a 12-bit ENOB...what does tht mean...how do we relate it to the output of the ADC??
3)Also when we use simulink to implement a DT-SDM we dont use a DAC??why??...do we use it only for a CT-SDM??
Any help wud be appreciated.
1)While calculating output power spectrum we take the FFT and plot only single sided spectrum...this is because the spectrum is symmetrical...but isnt the spectrum from -fs/2 to +fs/2??I have seen tht in most codes the 0 to fs interval is divided into N/2 points for a N-pt fft instead...so tht means the matlab fft function computes it from -fs to +fs...confusing for me...sorry if I have confused you
2)Doubt regd ENOB...what does it signify??when i simulate my ADC in simulink I get a sequence of +1 and -1(which are my quantization levels)...so when for example...it is a 12-bit ENOB...what does tht mean...how do we relate it to the output of the ADC??
3)Also when we use simulink to implement a DT-SDM we dont use a DAC??why??...do we use it only for a CT-SDM??
Any help wud be appreciated.