Cirrus Logic AN330 REV2 - Manual (Page 7)

AN330REV2 7
AN330
7 X
√
5 = 15.7 nVrms. The peak-to-peak noise would be 6.6 (±3.3 standard deviations) times 15.7 nV or
103.6 nVpp. Therefore, the resulting noise-free counts would be 5 mV / 103.6 nV = 48,253.
If lower-power operation is desired, the CS3011 operational amplifier could be substituted. Due to its lower operat-
ing current, the CS3011 amplifier has about 2x the noise of the CS3001. This would result in a reduction of the
noise-free counts by a factor of two.
In addition to the comments about the single opamp configuration made earlier, this circuit may have an offset drift
with temperature as the 88.7 k resistor temperature coefficient can be different from the load cell bridge resistors’
temperature coefficients.