BeSpice Wave is a perfect waveform viewer for ngspice as it supports it’s raw binary and ascii waveform format.
Ngspice is an open source spice simulator that is directly based on the legendary Berkley spice simulator. A raw waveform file is generated if the “–rawfile=FILE” command line option is specified when launching ngspice. This raw waveform file can be read be BeSpice Wave. All curves are listed in the browser window and can be plotted by dragging one or several of them to a page of the waveform viewer.
The raw file format that is used by ngspice can also be generated by other spice simulators. This includes open source simulators such as XYCE but also many commercial simulators. Check the documentation of your preferred spice simulator for the details.
Our free BeSpice Wave version can be downloaded from our downloads page. It has limited functionality but works perfectly for waveform files generated by ngspice.