Electrical & Computer
Op-Amp Lab
The ideal op-amp has a simple secret: with negative feedback it drives its two inputs to the same voltage (the virtual short), so the whole circuit's behaviour collapses to a ratio of resistors. This lab plots the transfer function Vout versus Vin as a straight line whose slope IS the closed-loop gain — −Rf/Rin for the inverting amp, 1 + Rf/Rin for the non-inverting one, or a weighted inverting sum of several inputs for the summing amp. Drag the resistors and the line tilts; drag the input and the operating point slides along it. The catch every first design runs into is built in: a real op-amp can't swing past its supply rails, so push the input too far and the line flattens into a clipped, saturated output. It's the fastest way to build intuition for the most useful building block in analog electronics.
-4.70×
Closed-loop gain
-0.94 V
Output Vout
Linear
Status
With negative feedback the op-amp holds its two inputs equal (the virtual short), so the gain collapses to a resistor ratio: −Rf/Rin inverting, 1 + Rf/Rin non-inverting. Push the input too hard and the output can't exceed its supply rails — the line flattens and the signal clips.
How to use this simulation
The ideal op-amp has a simple secret: with negative feedback it drives its two inputs to the same voltage (the virtual short), so the whole circuit's behaviour collapses to a ratio of resistors. This lab plots the transfer function Vout versus Vin as a straight line whose slope IS the closed-loop gain — −Rf/Rin for the inverting amp, 1 + Rf/Rin for the non-inverting one, or a weighted inverting sum of several inputs for the summing amp. Drag the resistors and the line tilts; drag the input and the operating point slides along it. The catch every first design runs into is built in: a real op-amp can't swing past its supply rails, so push the input too far and the line flattens into a clipped, saturated output. It's the fastest way to build intuition for the most useful building block in analog electronics.
Everything runs in your browser — no sign-up, no download. Change a value and the result updates instantly, so you can build a feel for how each input shapes the outcome. It pairs with Crameleon's practice exams and step sheets when you want to go from intuition to working the problems.