Hello,

I am learning about BJT working principle by following Chapter 4 of the Semiconductors vol. The explanation is very thorough and easy to follow. But when it mentions SPICE simulation with a netlist, for example, below, it does not provide information or link on how to run the simulation.

bipolar transistor simulation
i1 0 1 dc 20u
q1 2 1 0 mod1
vammeter 3 2 dc 0
v1 3 0 dc

.model mod1 npn
.dc v1 0 2 0.05
.plot dc i (vammeter)
.end

Can someone show me what the provided netlist can be done to demonstrate the explanation of the article.

Regards,
Dan

 

Hi dtus,
Welcome to AAC.
Have you installed in your PC either PSPICE or LTSpice.?
E

 

Hi dtus,
Welcome to AAC.
Have you installed in your PC either PSPICE or LTSpice.?
E

Yes, I have.

 

Yes, I have.

And I have drawn the schematic as shown on the article.

 

Hi,
Using LTSpice you would enter these values into the DC sweep analysis menu.
Also, a Common node symbol is required on the circuit

i1 0 1 dc 20u
v1 3 0 dc

.model mod1 npn
.dc v1 0 2 0.05

E

 

And I have drawn the schematic as shown on the article.
View attachment 324101

 

Hi,
Is your simulator PSPICE or LTSpice?
E

 

Hi,
This image shows the LTSpice version Netlist.
E

 

hi dtus,
Reading the text on that Article link, I have closely created what the writer stated.?
I have used the ' View Netlist' menu option.
E

 

Hi,
Using LTSpice you would enter these values into the DC sweep analysis menu.
Also, a Common node symbol is required on the circuit

i1 0 1 dc 20u
v1 3 0 dc

.model mod1 npn
.dc v1 0 2 0.05

E
View attachment 324102

I have tried defining the characteristics of Vammeter and I1 in their own lines as shown below (in the large dash box area) but could not run. To this, Spice shows an error of multiple instances ...

Assigning their characteristics via the DC sweep configuration window I could run the simulation but wondering which is the correct way to define characteristics of 2nd source (Vammeter) and 3rd source (I1)?

 

Hi,
Is your simulator PSPICE or LTSpice?
E

It is LTSpice.

 

Hi,
When the parameters are entered in the DC analysis menu then you cannot repeat them on the circuit diagram.
Try to run this asc file.

E

 

Hi,
This image shows the LTSpice version Netlist.
E
View attachment 324105

Thank you for taking the time to generate the simulation content.

I tried resembling your result and found that by probing on the I(vammeter), Spice generates 2 wave forms: one the grayish simply glides across the I1 0 20u 1u. What does another (the red) with constant 0A represent?

 

Hi dtus,
Please post your asc file and I will run it and reply.
E

Update: the Red line is when V1 is 0Volts, change V1 from 0 to 3 to 1 to 3

 

Hi dtus,
Please post your asc file and I will run it and reply.
E

Update: the Red line is when V1 is 0Volts, change V1 from 0 to 3 to 1 to 3
View attachment 324114

Please find the .asc file attached.

 

hi,
Check out this image.
As I said the Red line is when V1 is 0v in the DC analysis.
E

 

I see. Thank you very much for explaining all this.