Low noise opamp configuration.

[moda]

In voltage feedback opamp, can someone give full explanation what is the best configuration for low noise amp, is it inverting or none inverting? With the same gain. (like -2 gain or +2 gain)

 

[gevy]

For -2 gain output noise voltage equals 3*Vinput noise voltage,
but for +2 gain output noise voltage equals 2*Vinput noise voltage.
Hence +2 gain is better.
Besides, it is necessary to use gain not less than 5 or 10 to exclude noise of the following cascade of amplification.