Displayed here is a simplified typical sensor block diagram. The In Amp amplifies the sensor signal and passes it to the ADC, while the VA+ and VA- pins are used to sense the common mode voltage. The common mode voltage may provide important information regarding the health of the sensor, may be used to drive other circuitry in the system, or even for calibration of the system. The two precision voltage references maintain the accuracy of the signal as it is processed in the ADC thanks to the low noise and robust output. The 5 V reference may also power the sensor, if it is capable, for a ratio-metric design. Not shown is the microcontroller communicating with the ADC and selecting the gain of the ISL28533.