Spice Help Please.

Status
Not open for further replies.
Hi Again kinarfi,

Your .asc file didn't resolve to a functional circuit as a download, but I did get the jist of your request. I constructed a very simplified circuit, and have attached it below as an example of how to step the frequency of a source.

Note the structure of the .step spice command utilizing the parameter and LIST functions along with the return to original state (lower than original state works too).

EDIT: Or one can string it out to a limit using the proper/desired increments as shown in the second thumb.

I hope this helps.

Cheers,
Merv
 

Attachments

  • Freq Stepping Demo.jpg
    254.5 KB · Views: 404
  • Freq Stepping Demo 2.jpg
    253.4 KB · Views: 727
Last edited:
I have been building an engine speed controller and I have had to build it in pieces for spice, when I run the two pieces by them selves, they work great, but when I join them, I get a time step error. Can someone give me some help. The attached .asc works until I connect the wires to the left. I still need to add op-amp and FETs to drive some valves to the design, but I'm hung up with the error.
Thanks,
kinarfi
 

Attachments

  • untitled3.png
    25.3 KB · Views: 382
  • untitled2.png
    8.7 KB · Views: 371
  • Draft3.asc
    9.5 KB · Views: 421
Last edited:
Took a look at the yahoo's spice group and the first line said something about fet switches and op-amps and to much capacitance of the fet and that it causes oscillation and suggested the cure was to series a 10 or 100 ohm resistor, tried it and it cured my problem also.
 
Status
Not open for further replies.
Cookies are required to use this site. You must accept them to continue using the site. Learn more…