That’s the reason for the vast versions of SPICE available now decades after the original was released, not all of which are as open or free as we might like. Qucs is a GPL circuit simulator.

With this software, you can set ranges for various circuit components ... However, we appreciate the free release of this powerful simulator that can give LTSpice a run for its money.

“PICLS Lite is an incredibly simple to use free thermal simulation tool for electronic circuit boards, produced by the team behind leading electronics thermal simulation software, Cradle CFD. It ...