Re: how to calculate the THD+N=THD(%)+noise(nv^2/hz) in hspi
I am not sure
maybe you can use .four or .fft
but in A/D convert design need ENOB
and need know SNDR usually use .fft
I don't know why not use .four
as I know .four only analysis small singal
so someone tell me .fft more accuracy than .four
THD is simulated in transient and noise in ac
simulation. You cannot simulate noise unless
it isa systematic noise suc as quantization noise
In ADC's you can get THD+ quantization noise
through fft.