Multisim

Multisim is a circuit simulation software for both digital and analogue system. Through this virtual simulation, it ease the designer in designing as the designer can add and remove devices at any time.

Figure 1 shows the interface of Multisim. The highlighted red box is where the devices are located. With the Multisim V11.0, a lot more devices simulation are supported which includes PLC, and also some PIC16F microcontrollers.



Figure 1: Multisim Interface


Having devices is not sufficient to get data. Thus, Multisim includes various virtual instruments such as oscilloscope, multimeter and spectrum analyzer. Some of these instruments are based on instrument manufacturers such as Agilent and Textronix. Figure 2 shows the various instrument toolbar located at the right.



Figure 2: Instrument toolbar


Below is an example of a Bar Graph Display of AC signal. The AC signal will be produced by the signal generator and the signal wil be measured by an oscilloscope. Additionally, the amplitude of the signal will determine the display of the Bar graph. Devices and virtual instrument can be easily selected from the device toolbar and the instrument. The devices and instrment which are selected is put into the layout and connected.



Figure 3: Simple circuit example


Based on Figure 4, the oscilloscope which is used is from agilent. Besides that, the model also have the same layout of the original model.



Figure 4: Simulation of the circuit on oscilloscope


The signal generator which is used here is also from agilent which has the same layout as the original hardware.



Figure 5: Signal generator


Figure 6 shows the simulation. During simulation, you can manipulate the virtual instruments and view the results similar to what is shown on the oscilloscope and other output devices on the layout.



Figure 6: Result of the signal generator in oscilloscope

Conclusion

With this simulation software, circuit design and testing can be simplified as real hardware is not required. And the analysis can be done remotely with other engineers and designers for their recommendations and opinions.