How to fix ngspice simulation of Cree XLAMP CXB1507
The .model card has this syntax: .model &lt;model_name&gt; &lt;type&gt; &lt;parameters&gt;. In this case, the model is CXB1507, the type is a diode (d), and the parameters are the list that follows. 36V is not part of the syntax, so it's discarded, or gives an error. It's safe to remove that since it looks like it's meant to be a tag-like notation. Or you can add an underscore between the model and the offending characters, and it will count as a single model line: CXB1507_36V (don't forget to rename the diode using that .model, too).