Datasheet

AD7780
Rev. A | Page 10 of 16
OUTPUT NOISE AND RESOLUTION
Table 7 and Table 8 show the rms noise of the AD7780 for the two output data rates and gain settings when 3 V and 5 V references are used.
These numbers are typical and are generated using a differential input voltage of 0 V. The corresponding peak-to-peak (p-p) resolution is
also listed. The p-p resolution represents the resolution for which there is no code flicker.
Table 7. RMS Noise and Peak-to-Peak Resolution when AV
DD
= 3 V and V
REF
= 3 V
Parameter Gain = 128 Gain = 1
Update Rate 10 Hz 16.7 Hz 10 Hz 16.7 Hz
RMS Noise 44 nV 65 nV 2.4 V 2.7 V
P-P Resolution 17.6 17.1 18.8 18.7
Table 8. RMS Noise and Peak-to-Peak Resolution when AV
DD
= 5 V and V
REF
= 5 V
Parameter Gain = 128 Gain = 1
Update Rate 10 Hz 16.7 Hz 10 Hz 16.7 Hz
RMS Noise 49 nV 69 nV 3 V 2.7 V
P-P Resolution 18.2 17.7 19.3 19.4