harpoon
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Hi all,
I am getting confused with equations when going through this topic again.
Basically, for a Delta sigma modulator, the SNR_max (or Dynamic Range) is
10lg[(2^N-1)^2] +1.76+10lg[(2L+1)/pi^(2L)]+(2L+1)*10lg[OSR]
but for "Ideal Oversampling ADC with noise shaping", the SNR_max is
10lg[(2^N)^2] +1.76+10lg[(2L+1)/pi^(2L)]+(2L+1)*10lg[OSR]
i.e. the first term is higher for an ideal oversampling ADC with noise shaping ...
10lg[(2^N)^2] = 6.02N
and N= no of bits in quantizer, L=modulator order, OSR=oversampling ratio
Please see attached pic
Can someone clarify please ?
Thanks ...
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