May I have the reason why these two values are different ?
1) Calculated Effective Resolution of AD7176-2 based on AN-615.
SNR = 6.02N + 1.76 = 20log(peak-to-peak noise / full-scale input)
= 20xlog(0.000066/5x2) , Ext. REF = 5V
N = (103.609 - 1.76)/6.02 = 16.918 Bits
2) Data from Table 6. shows 17.3 Bits with peak-to-peak noise 66uVrms
Question 1) Why these two values are different ? Is there any wrong calculation ?
Question 2) AD7176-2 is 24bits ADC, then How can we get 24.7, 24.8, 24.9 and 25.1 Bits Effective Resolution ?
Thanks a lot.