Gain set by resistor ratios: -Rf/Rin and 1+Rf/Rg.
Inverting: A_v=-R_f/R_in, input impedance R_in. Non-inverting: A_v=1+R_f/R_g, very high input impedance. Closed-loop bandwidth = GBW/gain. Gain accuracy depends on resistor tolerance.
R_f=100 kΩ and R_in=10 kΩ gives -10; 1+99k/1k=100.
Gain set by resistor ratios makes op-amp circuits precise and predictable, so these two configurations are the most used in analogue design.
Gain set by resistor ratios: -Rf/Rin and 1+Rf/Rg.
Gain set by resistor ratios makes op-amp circuits precise and predictable, so these two configurations are the most used in analogue design.
Minus the feedback resistor divided by the input resistor, and the input is inverted.
It equals the input resistor, because the inverting input sits at virtual ground.
Typical applications include setting a gain of ten for a sensor amplifier with two resistors, building an inverting stage for an offset-corrected signal and choosing resistor values for a precision gain stage.
Study "Ideal op-amp rules" first (topic 18 of 104 in Electronics & Embedded). It covers the groundwork this topic builds on.
Virtual ground at inverting input. Buffer is unity non-inverting. Single supply bias needed.
R_f=100 kΩ and R_in=10 kΩ gives -10; 1+99k/1k=100.
The next topic is "Summing and difference amplifiers", which builds directly on this one.
It is classed as Beginner in Electronics & Embedded (topic 19 of 104). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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