The circuit is designed for dc or low-speed operation. Figure 1 Using single-supply, ground-referenced op amps, this circuit accomplishes an absolute-difference function.

Other phase-shift oscillators using low-pass ... outputs from this simple generator (d). A possible negative aspect of this circuit is that it requires a second op amp as a buffer with gain ...

For instance, op-amp input capacitance has a nonlinear behavior that’s a function ... circuit will exhibit large input impedance on dc as well. Figure 3 shows how the circuit can be adapted to ...