Altium Designer vs LTspice

Altium Designer has no write-up on Specifiction yet; its figures are above.

LTspice is a SPICE simulator, schematic capture tool and waveform viewer for analog circuit simulation. Its graphical schematic interface lets users probe a design, run simulations and inspect results in the built-in viewer. The download includes macromodels for most Analog Devices switching regulators and amplifiers, as well as a device library for general circuit simulation. Users can import third-party SPICE models implemented with .MODEL directives or .SUBCKT blocks. Designs from Signal Chain Designer, Analog Filter Wizard, Analog Photodiode Wizard, Precision ADC Driver Tool and LTpowerCAD can be exported to LTspice for simulation or verification. Tutorials address schematic creation, transient and AC simulation, waveform viewing, transformers, third-party models and noise analysis. The EngineerZone forum is available for questions and discussion. Analog Devices presents LTspice as an engineering design tool, with demo circuits and model libraries for designers. It is listed for Linux, macOS and Windows; the free plan specifies Windows and macOS downloads. A verified forum answer from an Analog Devices employee says telemetry is sent only if users opt in, and that the setting can be changed.