The OPAx171 family has an internal phase-reversal protection. Many operational amplifiers exhibit a phase reversal when the input is driven beyond its linear common-mode range. This condition is most often encountered in noninverting circuits when the input is driven beyond the specified common-mode voltage range, causing the output to reverse into the opposite rail. The input of the OPAx171 prevents phase reversal with excessive common-mode voltage. Instead, the output limits into the appropriate rail. This performance is shown in Figure 37.
|Input common-mode voltage||(V+) – 2||(V+) + 0.1||V|
|Noise at f = 1 kHz||30||nV/√Hz|