Introduction: This application provides a hands-on demonstration of various circuit configurations. The application allows the formation of a feed-forward circuit comprising a series of components such as voltage sources and op-amps of various configurations, and simulates and displays the results.
- Scrolling and Zooming: Either left-dragging within the display space, or using the arrow keys while your pointer is inside the display space, will scroll around the display space. The mouse wheel can be used to zoom in and out.
- Pregenerated Circuits: Clicking "Circuit 1," "Circuit 2," etc. will display a pregenerated circuit with a description of its function. Clicking "Random" will generate a random circuit. Clicking "Reset" will start with a new circuit.
- Adjusting Display: Clicking "Colorize" will alter the colors of the circuit. This is helpful for tracing connections in denser areas of interconnection. Clicking "Data Labels" will cycle through various presentations of the values (numeric, graphical, and none).
- Creating Circuit: Stages can be added and removed with "Add Stage" and "Remove Stage." (Stages are always added to and removed from the right, since inserting a stage can break connections between connections between components.) Circuit components can be added to or removed from the circuit by selecting a component and clicking "Add Component" or "Remove Component."
- Editing Components: Clicking on a component (either in the component list or in the schematic) will display its properties and enable editing. The input(s) of each component can be connected to a component from the preceding stage. (If you want to connect to a component in an earlier stage, you can add "wire" components in the stages in between.) Right-clicking on the input or output of any component will enable a connection with the output of any component at the next stage, or any input at the previous stage.
- Saving Circuit: As you create and edit the circuit, the URL of this page will change. You can bookmark the URL to save the circuit, or copy it from the address bar and email it to anyone else (but you may want to use a URL shortening service for that).
This project demonstrates the characteristics of various configurations of op-amps. The performance of each op-amp configuration can be tweaked by adjusting its elements, such as input resistors, feedback resistors, and capacitors. Cascades of op-amps can also be generated, where the output of one op-amp is provided as the input for one (or several) op-amps at the next stage.
Of course, this project is not a full-fledged circuit simulator such as PSpice; it does not perform mesh or nodal analysis, but simply allows the connection of components with various input and output voltages. Meshes and loops are not possible, because this project is strictly feed-forward. During each iteration, the simulation processes the components at each stage, and then uses the output to simulate the behavior of the components at the next stage, etc. (An interesting result of this limitation is that it's not possible to add a single resistor as a component - because its current and voltage drop is determined by the voltage both at the preceding stage and at the following stage.)
(C) 2015, David Stein. All rights reserved.