I missed the tiny "-" on fuzzy image .. Sorry differential output. I was wrong I was looking at R1 + input. oops (obvious now)
Refer to Friis formula on wiki
Note: TI has Fully-differential op-amps with an extra input pin (Vocm).
The purpose of this pin is to provide a place to input a potentially noisy signal that will appear simultaneously on both inputs
– i.e. common mode noise. The fully-differential op-amp can then reject the common mode noise.
The Guard pin (new).
https://www.ti.com/lit/an/sloa064/sloa064.pdf
The VOCM pin can be connected to a data converter reference voltage pin to achieve tight tracking
between the op-amp common mode voltage and the data converter common mode voltage. In
this application, the data converter also provides a free dc level conversion for single supply
circuits. The common mode voltage of the data converter is also the dc operating point of the
single-supply circuit. The designer should take care, however, that the dc operating point of the
circuit is within the common mode range of the op-amp + and – inputs. This can most easily be
achieved by summing a dc level into the inputs equal or close to the common mode voltage.
Is this for biomedical? If so, body has very high CM AC hum. or similar issue form SMPS nearby.