This example shows how higher fidelity or more detailed component models can be built from the Foundation library blocks. The model implements a band-limited op-amp. It includes a first-order dynamic from inputs to outputs, and gives much faster simulation than if using a device-level equivalent circuit, which would normally include multiple transistors. This model also includes the effects of input and output impedance (R_in and R_out in the circuit), but does not include nonlinear effects such as slew-rate limiting.
The op-amp is connected open-loop in this circuit, that is, in the form of a differential amplifier. This is to show the effect of the first-order dynamics. Including any feedback will reduce the impact of the dynamics on the circuit input-output response.