New MOSFET Schematic Symbols

Oct 17 2013, 4:30 PM PDT · 4 comments »

We've always had a single style of schematic symbol for MOSFETs within CircuitLab schematics, but we now have several options available. These three styles are "CMOS" (the original style), "ENH" for Enhancement-mode MOSFETs, and "ENH_BD" which adds a body diode to the symbol.

Here's a sample:

If you get mixed up while building your schematic, just mouse-over any terminal and CircuitLab will tell you if it's the drain or source!

New Plotting Features! - Cursor Lines and Math on Plots

Oct 09 2013, 2:00 PM PDT · 0 comments »

We're happy to announce a set of new features in our plotting engine! The new features include vertical and horizontal cursors and math functions that can be applied to the traces on your CircuitLab plots. Take a look at the video demo.

Circuit Parameters to Make Schematics Smarter

Oct 01 2013, 12:25 PM PDT · 3 comments »

CircuitLab now supports parameterized circuits, allowing you to define variables and have one or more circuit elements depend on those values. To add a parameter, find the "Parameter Element" in the toolbox, and set a name equal to a value. For example, "Rsrc" = "500" to create a variable with name Rsrc and value 500. You can subsequently reference the name Rsrc in any circuit elements you wish, and before running the simulation, the CircuitLab engine will compute and replace the parameter for you.

These sheet-wide parameters can include calculations, and can even reference each other. In effect, we've built a programming language layer to give you more control of your simulations!

This powerful feature can be used to drive simulations, sweeping multiple related values simultaneously, and can even calculate useful component values for you.

For a simple example, see a parameterized op-amp non-inverting amplifier, which calculates its own resistor divider values:

Open and run the simulations to see the gain-bandwidth tradeoff and the calculated resistor values!

For a more advanced example, take a look at this RF Matching Network, which calculates the correct inductor and capacitor value to use to perform an impedance match between source and load at 2.45GHz:

Open and run the simulations to see the narrowband power transfer maximum across frequency and the calculated capacitor and inductor values!

We hope you'll enjoy this powerful capability and push your simulations to the next level.

About CircuitLab

CircuitLab is an in-browser schematic capture and circuit simulation software tool to help you rapidly design and analyze analog and digital electronics systems.