34.1.1 Unity Gain Mode

The OPA module can be configured to operate in Unity Gain mode either in software or hardware, depending on the configuration of the Override Enable (OREN) bit. If the OREN bit has not been set, Unity Gain mode can be enabled in software by setting the Unity Gain Enable (UG) bit. Once Unity Gain mode has been enabled, the output of the OPA will be connected internally to the inverting input and the OPA will operate with unity gain feedback. If hardware-controlled override has been enabled by setting the OREN bit, the OPAxHWC register may be used to configure the OPA mode of operation, depending on the status of the override source. Refer to the Hardware Override Control section for more information.

Tip: Operating the OPA module in Unity Gain mode relinquishes the need for an external inverting input pin (OPAxIN-), since it connects internally to the OPA output, which allows that pin to be used for general purpose I/O.