LTspice can be utilized to perform statistical tolerance analysis for complex circuits. To show the efficacy of the method, this article presents a voltage regulation example circuit modeled in LTspice, demonstrating Monte Carlo and Gaussian distribution techniques for the internal voltage reference and feedback resistors. The results of this simulation are compared to a worst-case analysis simulation.
Included are four appendices: Appendix A provides insights on the distribution of trimmed voltage references. Appendix B offers an analysis of the Gaussian distribution in LTspice. Appendix C provides a graphical view of the Monte Carlo distribution as defined by LTspice. Appendix D lays out instructions for editing LTspice schematics and extracting the simulated data.