An Introduction To EDA Tools (Part 2)

BY Manu Prasad



Proteus ISIS is one of the best simulation software in the world for designing with electronic components including microcontrollers (MCUs). It is a handy tool to test programs and embedded designs. It is a virtual system modelling (VSM) that combines circuit simulation, animated components and microprocessor models to co-simulate complete MCU based designs.

This program allows you to interact with the design using on-screen indicators, LED and LCD displays, and even switches and buttons. One of the main components of Proteus is Circuit Simulation, using which you can simulate programming of the MCU. After simulating your circuit using Proteus software, you can directly make PCB design with it. It is an all-in-one package for designers and hobbyists.

To learn Proteus, you can get plenty of tutorials and video; the more you work on it, the better you become. In this section, we describe Proteus 8 Professional version for simulation. Follow the steps given below:

1. Open Proteus by double-clicking the icon on the desktop or navigating to the installed folder (normally the path is C:\Program Files (x86)\Labcenter Electronics\Proteus 8 Professional\BIN\PDS.EXE). Initially, a Home window will be displayed, which shows recent projects, getting-started tutorials, help, latest news and more.
2. To create a new project, go to File→New Project (Fig. 19). It will lead you to New Project Wizard, which helps to create a new project. Give sufficient details like schematic design, PCB layout and firmware. Select default value if you do not know the specifics, or create it later.

Fig. 19: Creating a project in Proteus

3. Finishing the wizard will create a default schematic design just like other EDA tools. Place the components on the schematic window. Placing can be done by selecting Pick Parts From Libraries option in Library menu or by using shortcut key P on the keyboard. This will open Pick Device window.
4. From Pick Device window, either search using the keyword or select the component category-wise (Fig. 20). Proteus supports a large variety of electronic components. Selecting each component shows a schematic and PCB preview with other details. Clicking OK will select the device and an image of that device will be shown when the mouse cursor moves over the schematic window. To place device, move the cursor where you want to and click over the schematic. Use Esc key to release selected device.

Fig. 20: Pick Devices window

5. After placing components over the schematic, connect their terminals by clicking-and-dragging technique. Moving the mouse cursor to the terminals will automatically show a pen symbol for drawing the connecting wires. In the left-most corner, multiple modes are present for other activities like component mode, wire label mode, buses mode, sub-circuit mode and more. You can select power supply, ground, input, output, etc from terminal mode. Probe mode is available for using test points, and an oscilloscope is available in instrument section for observing circuit outputs (Fig. 21).

Fig. 21: Schematic window

6. Ensure all connections are made and save the project before simulation. To run the circuit, go to Debug→Run Simulation or simply press F12. If you connect an oscilloscope to the circuit while running the simulation, a new digital oscilloscope window will pop up and show the waveforms (Fig. 22).

Fig. 22: Oscilloscope output

7. After successful simulation of the circuit, move to the PCB layout. Before going to the PCB design, ensure that all components have their own footprint. Like all other EDA tools, Proteus also has a different tool for PCB design, which is an integrated ARES PCB designing suite. Select Netlist option to ARES from Tools menu; it will open a new PCB layout design window.
8. Create a board edge. Select 2D Graphics Box Mode in the left corner and select Board Edge from the dropdown list in the left-most corner (Fig. 23).

Fig. 23: Selecting Board Edge option

9. On the workspace, draw a box of sufficient size in which you can place all the components. The circuit should be inside the yellow box; if circuit is complex, you can change the size of the box later.
10. Place each component outside the yellow box by right-clicking option Place→Component (Fig. 24).

Fig. 24: Placing the components

11. After adding all components to the workspace, arrange the positions of the components properly in the workspace.
12. Next step is tracking, which establishes the connection between components. Connection representation is in green line; yellow line shows direction. After setting track width, click on one end of the component with pen and follow the green line. When two components are successfully connected, the green line will automatically disappear. Multiple PCB layers are also possible in Proteus.
13. In Tool menu, options like auto router and auto placer can also be used by beginners, but manual routing and placing is recommended for better results.
14. To see a 3D image of the final circuit, click on Option 3D Visualization. The PCB layout can be printed from Print Layout option in Output menu.

Manu Prasad is M.Tech in VLSI and embedded systems and is currently working as assistant professor at AWH Engineering College. His interests include VLSI, EDA tools, MATLAB, Latex and so on.