Using Transformers in LTspice/Switcher CAD III - Analog Devices
Download the latest version of LTspice (the successor to SwitcherCAD III) directly from the Analog Devices Download Page. switchercad iii download
If you specifically need an older version for compatibility with older operating systems (like Windows XP), version "IV" is sometimes archived, though it is no longer updated. Using Transformers in LTspice/Switcher CAD III - Analog
Compute how a circuit behaves immediately after power-up by simulating the variable TIME . version "IV" is sometimes archived