JAJSGG2C October 2018 – June 2019 ADS125H02
The ADC incorporates a reference monitor to help detect a low or missing reference voltage. As shown in Figure 62, when the reference input voltage (VREF = VREFP – VREFN) falls below 0.4 V, the REFALM bit is set in the STATUS0 register. The alarm is read-only and resets at the next conversion after the fault condition is cleared. To implement detection of a missing reference voltage, use a 100-kΩ resistor across the reference inputs. If either positive or negative reference inputs become disconnected, the reference inputs are biased to 0 V differential, thereby triggering the low reference alarm. Poll bit 3 (REFALM) of the STATUS0 register to determine if the reference alarm has triggered.