Have you ever tried to install LTspice, but failed in the middle of typing while looking at a reference book or failed to get the desired result due to an error?　

To solve this problem, I'll show you how to perform a DC Sweep analysis using a simulation file that comes with you in a folder called Educational.

 

Educational folder

We will utilize the files provided in the Educational folder.

Open the DC Sweep analysis file

You can open the Educational folder in the following order : My Documents> LTspiceXVII> examples> Educational.

This time, open the file called "curvetrace. asc" from within the Educational folder.

This opened the circuit diagram of the bipolar transistor 2n222 shown in Figure.1.

Using this file, we confirm DC-Swep.

DC-Swep changes the value of DC to simulate the properties of the device.

Voltage value when the resistance value is changed

 

Configuring a DC Sweep Analysis

The DC Sweep analysis is configured as follows :

The red underline in ① indicates the setting of the voltage V1 between the collector and the emitter.

This means that V1 is swept in 10mV steps from 0V to 15V.

Right-clicking over the text opens the Edit Simulation Command (Figure 2).

If you select 1st Source, you can see the V1 settings.

The blue underbar in ② is the setting of the current I1 to flow to the base.

This means that I1 is changed from 20uA to 100uA in the 20uA steps.。

If you select the second Source of the Edit Simulation Command, you can see the I1 settings.

 

 

Check the I-V curve of transistor 2n222

When RUN is executed, the I-V curve shown in Figure. 3 is obtained.

You can check the I-V characteristics of another transistor by slightly modifying this file.

Also, change the current source I1 to a voltage source to check the I-V characteristics of the FET.

In the Educational folder, you will find examples of simulations other than the DC Sweep analysis presented here. I hope you will use it effectively.

 

LTspice download

LTspice can be downloaded through below URL link.

https://www.analog.com/jp/design-center/design-tools-and-calculators/ltspice-simulator.html