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BJT Characteristics

Description

This experiment is designed to plot the output characteristics of a generic BJT. The given BJT is connected in thecommon emitter configuration. The plot is of the output current against the voltage for the various values of inputcurrent. In other words, it is the plot of IC against VCE for different IB. For a constant IB the current increases as thevoltage increases till it reaches saturation. The characteristics are made up of three regions: cutoff, active andsaturation regions. At saturation, the VCE is almost zero and very high current flows. At cutoff, the output currentwill be zero. At the active region, the IC increases linearly with the VCE.

Procedure:

1. Connect the circuit as shown.The values of the DCsources don’t matter as they will be changed throughout theexperiment.

2. Click on Run and select the “DC with Sweep”. We are going to sweep two parameters. DCSource0 from 0 to 2V,Medium Accuracy. DCSource1 is configured as a current source. (This can be selected on the DC source by clickingon the “Voltage/Current” button). IB is supplied by DCSource1 and it is varied from 0 to 40 μA. And the VCE isvaried from 0 to 2 V by varying DCSource0.

3. Run the simulation and observe results on the plotter.

Conclusion

As VCE is varied the ammeter reading varies and becomes steady. The plots for each IB value are shown – as variedfrom 0 to 40 μA. The operating regions are as shown in the plot.

BJT CHARACTERISTICS BJT BASICS

AimAim is to plot the characteristics of a BJT

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