Circulator Amplifier with 4 Op Amps: How does it work? 

A 4-stage circulator amplifier designed with four Op Amps is analyzed in this circuit example video. This circulator amplifier has the unique property that the difference between the two neighboring voltages is a function of the sum of two other currents in the circuit. As an example V3-V4 = R*(i1 + i2). To prove this, a combination of virtual short for operational amplifiers and the Kirchhoff circuit laws including Kirchhoff Current Law or KCL is applied to quickly analyze the circuit and prove the circulator amplifier equation. It is also assumed that all op amps are biased properly and with dominant negative feedback that allows them to operate in the linear region of operation without saturation.