Data Sheet

AD7171

Rev. C | Page 9 of 16

OUTPUT NOISE AND RESOLUTION SPECIFICATIONS

Table 7 shows the rms noise of the AD7171. The numbers

given are for a 5 V and a 3 V reference. These numbers are

typical and are generated with a differential input voltage of 0 V.

The corresponding p-p resolution is also listed along with the

effective resolution (ENOB). Note that the effective resolution is

calculated using the rms noise, whereas the p-p resolution is based

on the p-p noise. The p-p resolution represents the resolution

for which there is no code flicker. These numbers are typical.

The effective number of bits (ENOB) is defined as

ENOB = ln(FSR/RMS noise)/ln(2)

The noise-free bits, or p-p resolution, are defined as

Noise-Free Bits = ln(FSR/Peak-to-Peak Noise)/ln(2)

Table 7. RMS Noise and Resolution of the AD7171

RMS Noise

P-P Noise

P-P Resolution

ENOB

5 V

11.5 μV

76 μV

16 bits

16 bits

3 V

6.9 μV

45 μV

16 bits

16 bits