Circuit Design - Simulation

PartSim is a free and easy to use circuit simulator that runs in your web browser. The PartSim software (full name Online Circuit Simulator with SPICE / Partsim) is written based on the popular SPICE utility, an open source electronic circuit simulator developed by the University of California. But unlike it, this development environment is adapted to the elemental base of electronic components with specific characteristics, which are supplied by the well-known distributor of radio components - Digi-Key Corporation.

SimulIDE is a simple real time electronic circuit simulator. It's intended for general purpose electronics and microcontroller simulation, supporting PIC, AVR and Arduino. PIC simulation is provided by gpsim and avr simulation by simavr. This is not an accurate simulator for circuit analisis, it aims to be the fast, simple and easy to use, so this means simple and not very accurate electronic models and limited features. Intended for hobbist or students to learn and experiment with simple circuits. SimulIDE also features a code Editor and Debugger for GcBasic, Arduino, PIC asm and AVR asm. Editor/Debugger is still in it's firsts stages of development, with basic functionalities, but it is possible to write, compile and basic debugging with breakpoints, watch registers and global variables.

Power Stage DesignerTM is a JAVA based tool that helps engineers accelerate their power-supply designs by calculating voltages and currents of 20 topologies according to the user’s inputs. Additionally, Power Stage Designer contains a Bode plotting tool and a toolbox with various functions to make power supply design easier. Because all calculations are executed in real time, this is the quickest tool to start a new power supply design.

An educational tool for designing and simulating digital logic circuits, featuring a simple-to-learn interface, hierarchical circuits, wire bundles, and a large component library. As a Java application, it can run on many platforms.

Do schematic capture, Spice simulation, PCB Layout online for free, then order high quality PCBs. EasyEDA: the one stop design shop for your electronics projects.