Help and Documentation

Getting started with DoCircuits

Frequenty Asked Questions


Q: I registered on DoCircuits. I got a message stating that I have to activate my account through email. But I didn't receive any mail as such.

A: Wait for some more time. You will get it. If not, then you can send an email to stating your user id.

Q: It takes a long time to load the virtual lab.

A: This could be due to a slow internet speed. Check your internet connection

Q: Which browser should I use to open DoCircuits?

A: DoCircuits works on all popular browsers like Safari, Chrome, Mozilla. But for best performance use Mozilla Firefox.

Q: I don’t get any confirmation message if I report a problem.

A: The confirmation will come. Since it requires time to send the request to server and get the response, the confirmation will come after a few seconds.

Q: I am new to electronics and have no idea as to what circuit to build.

A: You can click on "Trending Circuits" under "File" menu. This will open a list with a wide range of circuits to choose from. Click on them and load a circuit to get a hang of DoCircuits.


Q: How can I access the component library?

A: Double-click on the component to open the ‘Properties’ window. To your left you will see the component library from which you can select any component you want.

Q: Sometimes the shortcut keys like Ctrl+A, Ctrl+S, Ctrl+L don’t seem to work. Why?

A:  This happens sometimes if the focus is lost from DoCircuits to the browser. To bring back the focus click on an empty space on the grid.

Q: I am half-way in between building a circuit, but I have to logout. Can I save my work till that point?

A: Yes. Go to "File". Click on "Save As" to save a new circuit or "Save" to update an already saved circuit. To load the saved circuit click on "Load" under "File" menu. Alternately you can save the circuit in your computer by clicking on "Save to file" instead. And to load it click "Load from file".


Q: My simulation failed and I got a message stating "Simulation Runtime Error". What am I supposed to do next?

A: First check your circuit for the following points:

  • Have you given a very high frequency input signal? If so reduce the frequency.
  • Have you given a very high voltage input signal?. If so give a lesser voltage. 
  • Have you used any inappropriate devices? You can use the component library available for each component to choose a different type of component. 
  • Check if the design of the circuit is correct i.e. values of resistor, capacitor etc. are as per design
  • If you are using a transformer in your circuit  make sure that you use ground in both the primary and the secondary.

    Click on "Report a problem" to report your issue and our Support team will get in touch with you to help you out.

Q: In DC sweep, can I sweep the same parameter (say, R0) in both the sweep 1 and sweep 2?

A: No, you can't. This is not allowed because they are two different types of sweeps. Using them together for both sweeps has no meaning.

Q: How do I choose which simulation to run for which circuit?

A: It depends on what type of output you require. Say, you have a digital circuit, then you must run a time domain analysis only. If you have a circuit which works with only AC signals then you must not run DC analysis for it. DC analysis should be used for only DC circuits. Similarly frequency domain analysis should be done only for relevant circuits, not in a digital circuit for example. 

Q: How do I choose which analysis time and sampling time to set for time domain simulation?

A: It again depends on what the frequency of the signal you are processing in your circuit. Find the period of the lowest frequency used and plot for about 5 cycles. If still you are not sure click on "Set with Default Settings". Otherwise to be on the safe side use a small value like 10 ms to 100 ms for analysis time. DO NOT USE VALUES IN EXCESS OF 1 SECOND, THE SIMULATION MAY FAIL.  

Analyzing Output

Q: I closed the Plotter. How can I open it again?

A: You can click on “Analyze” on the top menu. Additionally if you want to open Oscilloscope or the Simulation Results, they are available in the drop down menu beside the “Analyze” button.

Q: I get confused with the various buttons and knobs on the virtual devices like CRO, function generator. Where can I find their functions?

A: Double click on the virtual device after dragging and dropping it.On the the top right corner of the virtual device you will find a "?" (question mark) symbol. Clicking on that will display the functions of each knob and button. This is the quick help view.Clicking on it again will bring you back to normal view. Otherwise to read a much more detailed Help section click on the "?" mark on the top right part of your screen which will redirect you to our Help page.