High-precision polarity conversion circuit composed of ordinary components

Because the loop gain of the OP amplifier mainly depends on the ratio of the input resistance and the feedback resistance, there is an error in the resistance value , and the gain will also have a corresponding error. To
obtain an accuracy of more than four digits, a high-precision resistor is required. The resistor Rs that reduces
the variable range of VRI has a resistance value of 1/100 of Rl and R2, so that the deviation of the resistance value
can be compensated . In fact, RL is g. 9kQ, Rz is 10.1 kQ. This worst-case scenario is very small, so the adjustable range of VRi is ±1%.