DoCircuits Now Accepting Registrations for International Online Circuit Design Competition “CircuitTrek 2013” for Students of Engineering and Technical Schools

In a recent announcement, the premier cloud based, Virtual Electronics Labs DoCircuits announced the International Online Circuit Design Competition “CircuitTrek 2013” open for registrations. CircuitTrek is an international online circuit design competition for students of engineering and technical colleges. The competition will run for three weeks and every week, the teams will be presented with a set of problems on circuits to solve. Teams have to solve the problems online on the Virtual Electronics Lab .


Teams would be evaluated on their problem solving capabilities, correctness of solution and out of the box thinking capabilities for design.

Talking about CircuitTrek, Debabrata Bagchi (Deb), CEO DoCircuits said, “Students in over 400 schools across the world use our Virtual Labs and we have created a vibrant ecosystem of electronics lovers. CircutTrek is another initiative to spread the love of electronics and bring our community together. Imagine students and schools from across the world competing and they can participate from their schools, homes and dorms.”

CircuitTrek has some interesting prizes lined up including Free full access to for 100 students from the top 3 teams cash prizes and more. “We are giving away prizes worth $10,000 this year,” Deb added. “However, personally I think LinkedIn/ Professional recommendation that we have for the winning teams will be much more valuable to the students.”

“I am an avid fan of everything science fiction, from Asimov to Star Wars and CircuitTrek has an interesting theme this year that perhaps reflects my passion,” Deb said. “Circuitship Enterprise has been hit by a gamma ray and Captain Diode needs help of Electronics Geeks to fix his ship. Are you up for the challenge?”

To know more about the competition check out CircuitTrek’s Facebook event and fill out this short form to register your team

About DoCircuits

DoCircuits is a premier Cloud Based Virtual Electronics. DoCircuits is changing the way students in Engineering and Technical Colleges learn electronics by empowering them with tools to conduct their Lab experiments online. Students get access to state of the art virtual test and measurement instruments and real life like components on the cloud. DoCircuits is being used by over 400 schools in over 150+ countries.

Schematic View Update

We have been listening to your feedback – and here is what some of you always wanted. We now have a symbol view of the schematic. What’s more – you can switch between the symbol view and the real view – using the button under the Run Button.

Schematic Symbol View

Symbol View

Once you click the Resistor Button under Run, the view will change to a real view and vice versa. The default view is now the symbol view.

Schematic Real View

Real View

Also note that while switching between symbol view and real view, if the sizes of the components are not consistent, some wires may disconnect. DoCircuits will flag this out if it happens. Finally, a meme to end this on a fun note. Enjoy the View !Switching between Symbol view and Schematic View

New: Add equations to DoCircuits!

Greetings from DoCircuits! Let’s start this blog with a simple experiment. Let’s say you’re asked to perform an experiment to find the power dissipated across a diode. Yes, you would connect a voltmeter and ammeter across a forward-biased diode, run the simulation, and take down the voltage and current across the diode. And finally you have to multiply the V and I values to obtain the power. Tedious isn’t it? How about if you were asked to the power dissipation across the diode with respect to the applied voltage? It’s not impossible. Well let’s see how we can do that too.

Let’s see the circuit that we have to rig up. The resistor is 1 kΩ.

After creating the circuit, click on the “Equations” tab to open the following window:

In the bottom of the equation panel you would find the measuring devices that are connected in the circuit, in this case the voltmeter and the ammeter. Above that you have all the mathematical functions and operators that can be used for your equation. The power equation is V * I. This equation can be added to the experiment as shown below:

Then click on “Add” to save the equation.

Clicking on the equation on the right hand column you can either edit the equation or delete it. In addition to that if you want the equation displayed on the grid along with the circuit for easy working, you can click on “Pin to Grid”.

Now vary the input voltage from 0 to 2 V and run the simulation. Plot the variables in the output plot with respect to the voltmeter value:

The plot shows the IV characteristics of the diode as well the power variation as calculated by the equation.

Thus using the mathematical functions available in the equations panel you can plot calculated variables.

Transistor biasing in amplifiers and Opamp Voltages

This applies to the problem of proper biasing in transistor amplifiers. Take a look at the diagram shown below:

The biasing on the left is the correct biasing while the one on the left is the incorrect one. The wire from Ci should be should be shorted with the resistor network as shown in the circuit and should not overlap it like the second example. In the case of the wrong biasing, since the base-emitter junction had got no biasing at all, the BJT never gets on and you will not get any output at all from the amplifier. Many people tend to make this mistake and thus the biasing of the BJT is not proper.

Opamp input voltages

When connecting a circuit with an opamp remember that the input voltages given to the opamp should not exceed the Vmax and Vmin values set in the opamp properties. Alternatively while using a five-pin opamp, the input voltages should not exceed the voltages set for the supply voltages for the opamps. If the opamp uses a supply of +15 to -15 V then the input should not cross this threshold. If it does happen  to then the circuit simulation may happen to fail. While designing the circuit, ensure that you give input voltages that do not exceed the voltage limit set by the opamp.

For any queries feel free to leave your comments.

Don’t forget the ground on both sides of a transformer circuit!

Hi folks, greetings from DoCircuits! It’s great to see everyone having fun learning with DoCircuits. As promised we have been introducing new features and components to enrich your learning experience on a regular basis. We hope you have found them useful and user-friendly. That on one side, we have found some recurring issues related to some type of circuits from the simulations you have run. Let’s try to get those issues addressed in this blog and the ones that follow.

Consider a basic full wave rectifier as shown below:

Note the ground that is connected at the transformer primary to the negative terminal of the input supply. Most circuits that you find online or in text books don’t show this ground and so you may not use it while connecting the circuit. But for our simulator to understand the negative terminal as a reference point a ground has to be connected. If that ground is missed the output will be zero when measured at the input. Similarly if ground is not connected at the secondary you will get an erroneous output.

A new DoCircuits offline

Hi folks! How is your lab experience going on with DoCircuits? You may have downloaded and used our offline version and you would have noticed that it looks and feels different from the online version and lacks chutzpah  So recently we launched a new, improved and cooler offline DoCircuits for you to work with. You can download it from the following URL:

So how different is it from your online virtual lab? Well apart from the fact that it’s offline, it’s actually a clone of the online version which keeps all your favorite features intact and much more. As you know the free version in has limitations but DoCircuits offline, once you get access to it, will be totally unlimited with respect to features.

So get started, it’s very simple. Go to the link above ( ) and download the setup file which is 39MB.  After installing, log in using your Online DoCircuits ID. You must be connected to the internet for activating your offline version and logging in for the first time. As part of this process, you must enter a license key to activate the tool. This is a paid feature, so you can go to the pricing page to find out how to get the license key ( For more information on installation click hereAfter that you will be redirected to our welcome page which introduces to some features for you to get started with. From then on working on this is just as you would work on the online version.

Welcome screen

The offline version has many advantages compared to the online version:

  • Faster simulations. As the simulation need not connect with our servers to obtain the result, simulations take place considerably faster. No more worrying about slow internet connections.
  • Save/Load compatibility. Let’s say you are working on the online version and are interrupted while doing an experiment. Save the experiment locally on your disk and that file could be loaded from the offline version and edited.
  • Full Version. In addition to the offline tool access the license key that you purchase will allow you full access to all features in the online version and also unlimited simulations and saved circuits.
  • Supports Windows for now. But DoCircuits will soon support Linux and Mac.

Now share your circuit results along with the circuit.

Hey everybody! Hope that you loved the new digital feature that we spoke of in the last post and that you are having fun Doing digital Circuits. So as promised we are adding more features and this new post is about another new feature we’ve introduced in DoCircuits.
Earlier if you were to share a circuit, you would get a link which contained the title of the circuit, its image and its description. But that is just half the job done. What about the result of that particular circuit? Won’t it be more informative if you could share – along with the circuit diagram – its output plot also? Well that’s exactly what you can do now with DoCircuits.
It’s quite easy. After simulating the circuit (if you don’t run the simulation it’s fine as while sharing you will be asked to) click on Share and in the ‘Share’window you will find a button to capture the output screen:

The share window

Click on the Share button. And you will be redirected to the plotter output where after setting which output to plot you can capture the screen image for sharing.

Click here to capture the image

Click on the “Capture Snapshot”button and you will redirected to the Share window. Click on Share and the circuit page will be shown. You can click on the Result tab on this page to view the result on the shared circuit page.

The result tab in the circuit page shown by the red circle

We hope this will be really useful to you and are happy to hear your comments.

Time to go Digital!

Hey everybody! Hope you all are having fun using DoCircuits! Well if a few of you are bored trying only analog circuits, then you are in for a treat as we have just launched fully digital simulation on DoCircuits. Now you can run complete digital simulations using this feature. You will work on digital components such as basic gates, encoders, decoders, multiplexers, demultiplexers etc.

Where you can find the digital button

To start with digital simulation, click on the “Digital” tab found on the Components Panel. This will display all the digital components. Drag and drop the components of your choice and rig up a circuit just as you would in Analog. For digital simulations we have provided special digital sources from which you can give input binary bits for processing. And just as in Analog, click on the “Run” button to open the simulation properties.

Digital Simulation Properties

You can either set the duration of the simulation in nanoseconds or click on default settings if you want. After clicking on the “Run” button a logic analyzer will load which shows the values of the digital signals measured in your circuit. The measuring will be done by labels that can be connected to output or the input. A circuit will look something like this:

A digital circuit

And your analyzer output will look something like this:

The logic analyzer

This analyzer shows all the plots that are measured. The logic levels are measured and along with that the scale is also displayed which can be varied.

Look out for flip flops and digital ICs in the near future. So go on have a try. Go digital DoCircuits style!

Light them up !


We are excited to tell you that we have added another complex visual animations to our LED component. We support 4 LED colors – and you can actually see them working as you can see in your real circuits.

Here’s a simple experiment you can try

LED Circuit Simulation

As the input changes, you can actually see the LED flashing for a few cycles. This circuits is easy to hook up – click on the picture to go the the public page of the circuit and launch it. or click here. Run the circuit, and close the plotter to see the LED’s flashing. If you want to run more cycles, go ahead and play with the Total time.

Have fun. Please leave your feedback and share your best LED circuits with us.

Your very own assistant to Do Circuits!

Hey everybody!! We at DoCircuits are bent on proving wrong all those that feel that electronics is boring and only for the nerds. As a result we will keep adding new features to make learning electronics easy and intuitive. Well how many of you had that feeling “What do I do after I land up on the Circuit Editor” ? “Or what am I to do next in this thing after dragging some components?” while Doing Circuits. You would have felt “do I have to read the Help section to know thoroughly what to do next?”

Well you will have something to guide you on how to build, run and share circuits from now on. We have introduced a feature called Workflow. Now every time you open our virtual lab a small window appears on right hand side of the screen.


The workflow window

There are three parts to it: build, run and analyze. And under each section you will find a set of instructions in red. Just follow what is given in them in order. As you complete the step the instruction turns green. Then you can go to the next step.


After completing a task

Complete each step until the plotter opens up showing the waveform plots. To know what to do next after plotting, close the plotter and see the workflow again.


After completing the workflow you will get some options on what to do next

You will have some options from which you can choose – like saving the circuit or sharing it – or to start building a new circuit.

Now those who found Doing Circuits slightly discomforting or new, now have a feature to assist them. Try it and give your comments!