DC inverting amplifier with gain determined by circuit ratio

Because the non-inverting auxiliary input terminal of the OP amplifier
is grounded, the internal resistance of the inverting input terminal is zero level, so the input resistance of the circuit is exposed
. If Rz remains unchanged, the input resistance increases with the gain. And decrease.
There is an input bias current IJ trapped in the OP amplifier. If no resistor Rs is added,
additional bias voltage will be generated. If a FET input type OP amplifier is used, Rs d can be omitted
~ Since the amplification is lo times, an offset adjustment circuit must be added. In the 741
type OP' amplifier, a 10k0 variable resistor is connected to the 1st and 5th leads. In
OP amplifiers without offset adjustment leads, a large
resistor should be added to the inverting input terminal to input a certain voltage (injection current). If a ±isv
power supply , the circuit is easily affected by power supply fluctuations and should be Please note.
    From the perspective of the entire amplification circuit , either the gain should always be determined based on the closed-loop frequency characteristics , or the OP amplifier
should be selected based on the open-loop characteristics .