ngspice-users

[Ngspice-users] How to make squarewave sweep

[Hannu V. <vu...@ms...>]

Hi!

My google-fu might not be perfect but I couldn't find any example how to sweep my connection with squarewave.

And I'm looking for 1ms on 1ms off 100 us on 100 us off 10 us on 10 us off kind of sweep.
I think I want transient analysis and somehow manipulate the vpulse parameters.

Best regards,
Hannu Vuolasaho
 		 	   		  

Re: [Ngspice-users] How to make squarewave sweep

[Robert L. <Rob...@t-...>]

Hello Hannu,

  I've appended something which might give
    you an idea starting point how to tackle this.

  You will need a "while" or similar loop in a
    ".control" section.
  Within the loop you will need an
    "alter" to change the v PULSE instance,
    and a "tran" to run simulation with this new
    v pulse source.
  Then you will need to collect somehow the
    data which you are after, or plot them altogether
    with something like
       plot tran1.v(n1) tran2.v(n1) ..

  The first attached piece just shows you a bit of syntax
    to do the "alter".
  The second attached piece shows you a "foreach" loop
    and a way to collect the plot names, and how to
    plot them all in one. This one runs "dc" instead
    of your "tran". (For the name concatenation you
      will need a sufficiently new ngspice)

Regards,
 Robert

altering the second parameter of a `pulse' VSRC device
* (compile (concat "w32/src/ngspice " buffer-file-name) t)

vaph1 aph1 0 pulse 0v 0.042ns .50ns .01ns  .01ns .99ns 2ns

.control

show vaph1
let pulse_v1 = @vaph1[pulse]

* print status quo
print pulse_v1 @vaph1[pulse]

* alter the second vaph1 pulse parameter
let pulse_v1[1] = 0.43ns

alter @vaph1[pulse] pulse_v1

* verify
show vaph1
print pulse_v1 @vaph1[pulse]

.endc

-----

* (exec-spice "ngspice %s" t)

i1  0 1  dc 100u
d1  1 0  dplain

.model dplain   d(is=1.0f)

.control

set them = ( )
set signals = ( )

foreach is 0.1f, 1f, 10f

  altermod dplain is $is
  dc i1 200u 1000u 200u

  set them = ( $them $curplot )
  set signals = ( $signals {$curplot}.v(1) )

  echo "curplot = $curplot"
  echo "curplottitle = $curplottitle"
  echo "curplotname = $curplotname"
  set curplottitle = "p_title is=$is"
  set curplotname = "p_name is=$is"

  * on unix, curplottitle will be in the windowmanagers frame
  *   which is around the plot window
  plot v(1)
end

* plot them all together
echo "signals = $signals"
plot $signals

* plot one,
setplot $them[1]
plot v(1)

.endc

Hannu Vuolasaho <vu...@ms...> writes:

> Hi!
>
> My google-fu might not be perfect but I couldn't find any example how
> to sweep my connection with squarewave.
>
> And I'm looking for 1ms on 1ms off 100 us on 100 us off 10 us on 10 us
> off kind of sweep.
> I think I want transient analysis and somehow manipulate the vpulse parameters.
>
> Best regards,
> Hannu Vuolasaho

Re: [Ngspice-users] How to make squarewave sweep

[Andy F. <and...@si...>]

You could try using the XSPICE Controlled Squarewave Oscillator:

http://ngspice.sourceforge.net/docs/ngspice-manual.pdf#subsection.12.2.22

or you might like to play with this idea I was tinkering with:

https://easyeda.com/andyfierman/Basic_behavioural_VCO_based_on_integrator_and_modulo_divider_function-omgysK2ke

Cheers,

         Andy.

signality.co.uk

On 20 September 2015 at 14:23, Hannu Vuolasaho <vu...@ms...> wrote:

> Hi!
>
> My google-fu might not be perfect but I couldn't find any example how to
> sweep my connection with squarewave.
>
> And I'm looking for 1ms on 1ms off 100 us on 100 us off 10 us on 10 us off
> kind of sweep.
> I think I want transient analysis and somehow manipulate the vpulse
> parameters.
>
> Best regards,
> Hannu Vuolasaho
>
>
> ------------------------------------------------------------------------------
> _______________________________________________
> Ngspice-users mailing list
> Ngs...@li...
> https://lists.sourceforge.net/lists/listinfo/ngspice-users
>

Re: [Ngspice-users] How to make squarewave sweep

[Hannu V. <vu...@ms...>]

Thanks guys.

Unfortunately I'm not that fluent with spice. Controlled square wave oscillator looks something,
I could use. However reading through the manual sections I couldn't figure out it thoroughly.

If I understood correctly manual, I could put simple RC filter to ControlVin and get 
capacitor charging ramp to frequency from pulsesOut? or pwl source.

ain ControlVin PulsesOut pulse1
.model pulse1 square(cntl_array = [ 0 10]
+                    freq_array=[10 10000] out_low = 0.0
+                    out_high = 5 duty_cycle = 0.5
+                    rise_time = 1e-6 fall_time = 2e-6)

With ControlVin I get the frequency.

Am I totally wrong?

Hannu Vuolasaho
________________________________
> From: and...@si... 
> Date: Sun, 20 Sep 2015 19:00:19 +0100 
> To: ngs...@li... 
> Subject: Re: [Ngspice-users] How to make squarewave sweep 
>  
> You could try using the XSPICE Controlled Squarewave Oscillator: 
>  
> http://ngspice.sourceforge.net/docs/ngspice-manual.pdf#subsection.12.2.22 
>  
> or you might like to play with this idea I was tinkering with: 
>  
> https://easyeda.com/andyfierman/Basic_behavioural_VCO_based_on_integrator_and_modulo_divider_function-omgysK2ke 
>  
> Cheers, 
>  
>           Andy. 
>  
> signality.co.uk<http://signality.co.uk> 
>  
> On 20 September 2015 at 14:23, Hannu Vuolasaho  
> <vu...@ms...<mailto:vu...@ms...>> wrote: 
> Hi! 
>  
> My google-fu might not be perfect but I couldn't find any example how  
> to sweep my connection with squarewave. 
>  
> And I'm looking for 1ms on 1ms off 100 us on 100 us off 10 us on 10 us  
> off kind of sweep. 
> I think I want transient analysis and somehow manipulate the vpulse  
> parameters. 
>  
> Best regards, 
> Hannu Vuolasaho 
>  
> ------------------------------------------------------------------------------ 
> _______________________________________________ 
> Ngspice-users mailing list 
> Ngs...@li...<mailto:Ngs...@li...> 
> https://lists.sourceforge.net/lists/listinfo/ngspice-users 
>  
>  
> ------------------------------------------------------------------------------ 
> _______________________________________________ Ngspice-users mailing  
> list Ngs...@li...  
> https://lists.sourceforge.net/lists/listinfo/ngspice-users 
 		 	   		  

Re: [Ngspice-users] How to make squarewave sweep

[John D. <jp...@no...>]

On Sep 20, 2015, at 12:46 PM, Hannu Vuolasaho <vu...@ms...> wrote:

> or pwl source.

That’s what I do for complicated stimuli. I write a little program in some scripting language to emit a PWL source.

John Doty              Noqsi Aerospace, Ltd.
http://www.noqsi.com/
jp...@no...

Re: [Ngspice-users] How to make squarewave sweep

[Tom <mad...@go...>]

On 20/09/15 14:23, Hannu Vuolasaho wrote:
> Hi!
>
> My google-fu might not be perfect but I couldn't find any example how to sweep my connection with squarewave.
>
> And I'm looking for 1ms on 1ms off 100 us on 100 us off 10 us on 10 us off kind of sweep.
> I think I want transient analysis and somehow manipulate the vpulse parameters.
>
> Best regards,
> Hannu Vuolasaho
>   		 	   		
> ------------------------------------------------------------------------------
> _______________________________________________
> Ngspice-users mailing list
> Ngs...@li...
> https://lists.sourceforge.net/lists/listinfo/ngspice-users
>
If its not too big PWL would do.
I sometimes write external macros to produce the input I want if they 
are long.
Tom