LT Spice Subcircuit Problems

Discussion in 'General Electronics Chat' started by newbie217, Sep 29, 2011.

  1. newbie217

    Thread Starter Active Member

    Apr 12, 2009

    I've read the FAQ, but still can't get a LM555 subcircuit to run properly.

    I've copied the symbol to folder:
    C:\Program Files\LTC\LTspiceIV\lib\sym\mylib\LM555.asy

    If I copy the subcircuit into the folder:
    C:\Program Files\LTC\LTspiceIV\lib\sub\LM555.sub

    LTSPICE can find the subcircuit and execute properly.

    If I relocate the subcircuit to folder:
    C:\Program Files\LTC\LTspiceIV\lib\sub\mylib\LM555.sub

    The subcircuit can no longer be found. I've made sure to include the Spice line:

    .lib "C:\Program Files\LTC\LTspiceIV\lib\sub\mylib\LM555.sub"

    I also tried saving the LM555.sub into file LM555.lib, but no luck either.

    What am I doing wrong?
  2. SgtWookie


    Jul 17, 2007
    You did it right, here:
    You'll save yourself a lot of trouble if you just keep your .sub and .lib files in the C:\Program Files\LTC\LTspiceIV\lib\sub directory. The .asy files you can put in various subdirectories, but I suggest pretty much sticking with the established directory structure - otherwise, if you're swapping .asc files around with other people for troubleshooting or whatever, you can wind up having problems loading the symbols.
    newbie217 likes this.