AFE5801: AFE 5801 SNR

Hi,

Thanks for using AFE5801 device.

for your question:

This is noise density for 100dB.

 After integrating BW, then we get 70dBFS SNR.

Thank you!

Best regards,

Chen

GBiswal, 

 Noise density may not be exact accurate. actually it is the FFT BIN noise density.  

in the datasheet, the plot is run at N point FFT, each bin is about Fs/N. then in your equation, the BW is that BIN size. Fs/N. 

Thanks!

Hi,

Please refer to the AFE5801 Datasheet page 37

SNR = 10*Log10(PS/PN)

where PS=Power of Fundamental signal

PN=Power of total Noise

As you have seen from the plot, that is only one bin of the noise which is 100dBFS

(in this case)

Thank you!

Best regards,

Chen

GBiswal, 

it will be the Fs/N.  The plot only showing the real part from 0 to Fs/2, the imagery part is -Fs/2. 

for the SNR plot, you can refer to the AFE5801EVM user manual. there are calculation point as 64K points. 

Thanks!