Hello, until now I’ve been a loyal LTSpice user, but may switch to QSpice, in view of some new interesting features and also that Mr. Engelhardt is pulling the strings 
However, I see no support for IGBTs. None appears in Onsemi’s list of models. You cannot bueild IGBT models on your own either. Plus, LTSpice’s IGBT version of the Z component, seems to have been discontinued.
So my question is, do you (=Qorvo, Qspice) plan to include IGBT support in the near future?
IGBT support is important for me.
Thank you and regards, Unai.
This question arises out of curiosity about how you are currently working on IGBTs in LTspice.
The Z-device NIGBT in LTspice is based on the original work by Robert Ritchie of Analog Devices, potentially involving considerations for intellectual properties. However, in general, very few devices use this model.
The prevailing approach is that IGBTs are complex devices and are typically modeled as subcircuits. The native model of IGBT cannot be found in SPICE-based simulators like Pspice, NGspice, Hspice, etc. This raises the question: what does “IGBT support” entail? Typically, manufacturers provide subcircuit netlists that can be used as subcircuit devices in SPICE.
Hello KSKelvin!
Let me rephrase my overall doubt/question as three specific questions:
- Does QSpice plan to implement NIGBT “dynamics” (as a .model card for the Z element), as Mr. Engelhardt did with the VDMOS model in LTSpice, which has been ported to QSpice?
- If yes: then, does QSpice plan to add IGBT model creation capabilities to the model creating tool?
- Anyway, does QSpice plan to include support for Onsemi’s IGBTs? (indeed you might support them via the .subckt card. i.e. not necessarily via a .model card).
I came up with these doubts when reading a recent article in Bodo’s Power Magazine (Nov. 2025 issue), by Qorvo’s S. Mahan, showcasing QSpice’s model creation tool (BTW an excellent tool; congratulations 
). Then, I remembered Mr. Engelhardt saying in a video something like “the main reason you switch to a new simulator is to do things you cannot do with your current favorite simulator”. I apologize because I don’t remember the exact source or words, but I do remember what the message was.
So, I said to myself, maybe the guys at Qorvo are willing to take on the issue of IGBT modelling. Maybe the deal Qorvo made with Onsemi helps…
Thank you and kind regards
LTspice had a built-in IGBT transistor model similar to the model in Pspice. I even made it for one transistor. I also upgraded the Pspice model because in the initial state they did not model the characteristics in LTspice well. I’ve also seen bad reviews about these models. I don’t know if there is a built-in IGBT model in the new versions of LTspice. I have a lot of models in the form of subcircuits and I don’t see any special need for an integrated IGBT transistor model.
There is a history involving Qspice with Onsemi JFET and SiC devices. Onsemi acquired the SiC JFET business from Qorvo in early 2025, leading to the transfer of those models from the Qorvo directory to the Onsemi directory in the Qspice symbol library.
For the model generator, Qspice includes MOSFET, Diode, and JFET model generators. There was a question as to why BJT is not included. Mike explained that in most cases, the manufacturer datasheets of BJTs do not contain enough information for model generation, but I cannot recall where I heard this.
IGBT is a device that combines MOSFET and BJT technology. Perhaps such a challenge will persist. It is interesting to note that in SPICE history, there seems to be no successful IGBT device model. While we have seen different levels of MOS and BJT models, IGBT models are lacking. I have always had the impression that since IGBTs are a combination of MOSFETs and BJTs, the model should make more sense as a subcircuit, incorporating both types of devices.