Rakhiwarriar: Created page with ''''Title of the Script:''' DC sweep analysis in ngspice '''Author:''' '''Abhishek''' '''Keywords: '''video tutorial,''' '''ngspice. {| style="border-spacing:0;" | style="bor…'

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Created page with ''''Title of the Script:''' DC sweep analysis in ngspice '''Author:''' '''Abhishek''' '''Keywords: '''video tutorial,''' '''ngspice. {| style="border-spacing:0;" | style="bor…'

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'''Title of the Script:''' DC sweep analysis in ngspice

'''Author:''' '''Abhishek'''

'''Keywords: '''video tutorial,''' '''ngspice.

{| style="border-spacing:0;"
| style="border-top:0.1pt solid #000000;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>'''Visual Cues'''</center>
| style="border:0.1pt solid #000000;padding:0cm;"| <center>'''Narration'''</center>

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Slide 1</center>
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| Welcome to this '''spoken''' '''tutorial''' on “'''DC sweep analysis in Ngspice'''”

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Slide 2</center>
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| In this tutorial we will learn,

To perform,

'''DC sweep analysi'''s and

'''Nested DC sweep analysis.'''

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Slide 3</center>
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| Basic knowledge of '''electronic''' '''circuits''' is a prerequisite for this tutorial.

Basic knowledge of '''Ubuntu''' '''Linux''' and '''shell''' '''commands''' is also required.

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Slide 4</center>
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| '''Ubuntu''' 12.04 is the '''operating''' '''system''' used with '''ngspice''' '''version''' 23 installed.

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Slide 5</center>

<center>(hover '''mouse''' over '''circuit''' '''diagram)'''</center>

<center>(show '''nodes''' 1,2,3)</center>
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| We will use the example '''circuit''' shown.

The '''circuit''' consists of three prominent '''nodes''' '''“1”, “2” and “3”. '''

In addition, a fourth '''node''' called as '''reference OR datum node''' must be marked as node '''“0”.''' This is mandatory for any '''circuit.'''

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Demonstration</center>

<center>Go to '''gedit''' '''window''' with '''example.cir''' '''file,''' which is already open</center>

<center>hover '''mouse''' over '''components''' and '''node''' information</center>

<center>hover '''mouse''' over '''.dc'''</center>

| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| Let us open the '''ngspice''' '''netlist''' '''file''' '''example.cir''' corresponding to the '''circuit''' '''schematic''' shown before, in a '''text''' '''editor'''.

I have already opened this in '''gedit text editor'''.

Note that '''netlist''' '''file''' is saved with '''.cir''' '''extension'''

We can see all the '''components''' like '''voltage''' '''source,''' '''resistors''' and information about '''nodes''' connecting them together.

'''dc''' '''command''' included in '''netlist''' '''file''' is used to perform '''dc sweep analysis'''.

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Go to slide no 6</center>
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| General form to use '''dc''' '''command''' is as shown,

'''dot dc SRCNAM VSTART VSTOP VINCR'''

where,

'''SRCNAM''' is name of '''independent''' '''voltage''' or '''current''' '''source.'''

'''VSTART, VSTOP and VINCR''' are the starting, final and increment values respectively for the '''source.'''

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Go to the '''text''' '''editor''' '''(i.e)example.cir'''</center>

<center>Hover '''mouse''' over '''.dc''' '''command''' '''statement'''</center>

| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| As you see we are sweeping '''voltage''' '''source''' V1 for a single value of 24 '''VOLTS''' with step increment of 1.

Now we will '''simulate''' this '''circuit,''' and find out '''voltage''' values at different '''nodes.'''

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"|
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| let us open '''ngspice''' through '''terminal.'''

Press '''Control Alt T''' together.

This will open the '''Terminal''' '''window.'''

Now I go to the '''folder''' where the '''netlist''' '''file,''' '''example.cir,''' is '''saved.'''

I do this as follows:

'''cd downloads path to the folder '''and press '''Enter.'''

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>'''Type''' the '''commands''' as mentioned</center>
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| Now let us '''simulate''' the '''ngspice''' '''file.'''

Let us see how this can be done.

On '''terminal,'''

Type '''ngspice '''space''' example.cir''' and press '''Enter.'''

Value of '''voltage''' v1 is 24 '''volts.''' Value of '''voltage''' v2 is 9.746 '''volts.'''

Other '''node''' '''voltages''' are also displayed.

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Show slide 7</center>
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| Next we will see how to do '''nested dc sweep analysis.'''

Generalized form for this is as shown.

'''Dot DC SRCNAM VSTART VSTOP VINCR SRC2 START2 STOP2 INCR2'''

where,

'''SRCNAM''' is the primary '''sweep''' '''variable''' and '''SRC2''' is the secondary '''sweep''' '''variable.'''

Secondary '''sweep''' '''variable''' forms the outer loop.

That is for every increment of secondary '''sweep variable,''' the first '''sweep variable''' is stepped through its entire range of values.

It will be more clear with the example '''circuit''' we will '''simulate.'''

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| Slide 8

Hover '''cursor''' over '''vin.'''

Hover '''cursor''' over '''Rload'''
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| We will use '''Bipolar junction transistor '''based '''circuit''' in '''common base''' configuration.

Primary '''sweep variable''' is '''voltage''' '''Vin''' connected between '''emitter''' and '''base''' '''terminals.'''

Secondary '''sweep''' '''variable''' will be the '''load''' '''resistor''' '''Rload.'''

We will '''plot''' '''output voltage '''versus '''input voltage '''for different values of the '''load resistor'''.

The output voltage is the voltage across Rload and the input voltage is '''Vin'''

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| Open the '''file example-nested.cir''' already open in '''gedit'''

| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| Following is the '''netlist''' corresponding to the '''common base transistor circuit.'''

'''NPN''' is the '''default''' '''model''' used for '''transistor,''' '''mod1''', in the '''circuit.'''

As you can see Vin is varied from 0.2 '''volts''' to 2 '''volts''' with step increment of 0.02 '''volts.'''

'''Rload''' is varied from '''5kiloohms''' to 10 '''kiloohms''' with step increment of '''2kiloohms'''

For different values of '''Rload, Vin''' is swept through the complete range of 0.2 to 2.

Graphs of '''output''' '''voltage''' versus '''input''' '''voltage''' is plotted in each case.

'''Plot v of 3,4''' plots the '''voltage''' '''drop''' between the '''nodes''' 3 and 4, that is the '''voltage''' across '''Rload.'''

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Go to the '''terminal''' '''window.'''</center>

<center>On the '''terminal''' type </center>

<center>'''source example-nested.cir''' and press '''Enter.'''</center>

| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| Now we will '''simulate''' this '''circuit''' and see the results.

On the '''terminal''' type '''source space example nested.cir '''and press '''Enter.'''

This will '''run''' the '''simulation.'''

'''source''' '''command''' is used to '''simulate''' the '''netlist''' from within the '''ngspice'''

'''simulator''' '''environment'''

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>On '''terminal''' type, '''quit.''' Press '''enter.'''</center>
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| As you can see graph of '''output voltag'''e versus '''input voltage''' is plotted for different values of '''load''' '''resistor.'''

Quit the '''ngspice''' '''simulator''' by typing '''quit''' and press '''enter.'''

Here we come to the end of this '''tutorial'''

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Slide 6</center>
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| In this tutorial we learnt,

To perform,

DC sweep analysis of a given circuit.

Nested DC sweep analysis of a given circuit.

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Slide 7</center>

| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| Watch the video available at the following link

* It summarizes the Spoken Tutorial project

* If you do not have good bandwidth, you can download and watch it

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Slide 8 </center>
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| The Spoken Tutorial Project Team

* Conducts workshops using spoken tutorials

* Gives certificates for those who pass an online test

* For more details, please write to contact at spoken hyphen tutorial dot org

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"| <center>Slide 9</center>
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| Spoken Tutorial Project is a part of the Talk to a Teacher project

* It is supported by the National Mission on Education through ICT, MHRD, Government of India

* More information on this Mission is available at

* spoken hyphen tutorial dot org slash NMEICT hyphen Intro

|-
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:none;padding:0cm;"|
| style="border-top:none;border-bottom:0.1pt solid #000000;border-left:0.1pt solid #000000;border-right:0.1pt solid #000000;padding:0cm;"| Thank you for joining.

Hope you found this tutorial useful.

This is Anuradha Amrutkar signing off.

|}

Ngspice/C2/DC-Sweep-Analysis/English - Revision history

Rakhiwarriar: Created page with ''''Title of the Script:''' DC sweep analysis in ngspice '''Author:''' '''Abhishek''' '''Keywords: '''video tutorial,''' '''ngspice. {| style="border-spacing:0;" | style="bor…'