Typical SPICE-based simulator is intended for an accurate analysis of a "real" circuit. It uses quite complex models of "real" components, most of which are provided by parts manufacturers. Standard SPICE algorithm has a lot of limitations. Convergence problems may occur even for very simple circuits. For some types of circuits (especially switching), wrong result can be easily obtained, just due to numerical methods used in SPICE.
Unlike SPICE, NL5 does not have complex and "accurate" models of non-linear components. Instead, it uses very simple models as much as possible: "ideal" switches and diodes, amplifiers with infinite gain, etc. Some non-linear behaviour can be modelled with piece-wise linear approximation, however most of the time it is not needed at all. Using simple components results in fast and reliable simulation, with almost no convergence problems.
There are some common features in NL5, PSIM, and Simplis. For example, a switch can open/close at one simulation step, without detailed calculation of the entire switching process ("instantaneous switching"). Other than that, NL5 is very different in terms of its idea, implementation, performance, and features.
A major difference is that NL5 does have "true" ideal switches and diodes, with zero impedance when closed, and infinite impedance when open. PSIM and Simplis always require some small and large impedance to be set.
After installing Microsoft® Security Updates 925902 and 928843 (MS07-017 and MS07-008, issued on February 13 and April 3, 2007), some programs, including NL5, don't start and will display the following error message. To fix the problem, Microsoft® has issued a patch for this update. We apologise for any inconvenience that these vitiated MS® Security Updates may have caused.
A license file is located in the same directory as executable nl5.exe;
A name of the license file is exectly nl5.nll. You might need to turn off an option "Hide extensions for known file types" in Windows Explorer, to make sure there is no any other extension in the file name (for example, "txt");
If you receive a license file as an attachment in the email, simply copy the attachment in the NL5 directory. Do not copy the text from the license file manually!
NL5 License Server is a Windows application, and cannot run as s service. However, along with a Network License file nl5.nll, you will receive a service application NL5LicenseService.exe. Contact your IT department for proper service installation. Please note that service application does have all required license information built into it, so you do not need license file nl5.nll while using the service.