The input impedance of the current opamp is generally very high, so the opamp signal input resistance choice is relatively large. However, the input impedance of reverse amplification is not large, so when reversing amplification, the internal resistance of the signal source should be considered. Usually in order to reduce the impact of bias current, as well as reduce the impact of noise and temperature drift, the input resistance is generally selected in the range of 10k ~ 100k.
The amplification factor of inverted phase amplification is the feedback resistance divided by the input resistance. The in-phase end is grounded through a resistance. Generally, this resistance is chosen to be equal to the parallel value of the inverse input resistance and the feedback resistance.