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Using NISM Control Loop Stability Analysis in PSpice (Video)

Video demonstration showing how to implement NISM (Normalized Impedance Stability Modeling) control loop stability analysis techniques in PSpice. This practical tutorial walks through the setup and execution of stability analysis using PSpice simulation tools.
How to Quantify Flat Impedance and Control Loop Stability with PSpice (Video)

YouTube video tutorial explaining how to quantify flat impedance characteristics and perform control loop stability analysis using PSpice. Learn practical techniques for measuring and analyzing impedance behavior in power supply designs.
Introduciton to NISM for PSpice (PowerPoint)

Comprehensive PowerPoint presentation introducing NISM (Normalized Impedance Stability Modeling) concepts and implementation in PSpice. This educational resource covers fundamental principles and practical applications for control loop stability analysis.
Solving SPICE Convergence Problems

This application note covers a series of structured solutions to solve common SPICE convergence problems. The guide provides step-by-step instructions to solve stubborn DC, DC Sweep, and Transient convergence issues. Discussions of common mistakes and the setting of OPTIONS parameters are covered.
SPICE Models Need Correlation to Measurements

Many SPICE models are available online that were created by IC and semiconductor manufacturers. Unfortunately, availability doesn't necessarily equal usability. The majority of these models have no documentation or detailed description of the model's capabilities. More importantly, the limitations aren't discussed. This can leave you wondering what the model is and isn't good for and under which operating conditions it is valid. This presentation discusses the limitations of 'free' SPICE models found online.
Lessons Learned from SPICE

Space Power Workshop Presentation, May 8, 2014. Accurate analysis relies to a large degree on accurate SPICE models and modeling capabilities. This presentation highlights many of the issues surrounding IC vendor and EDA software vendor supplied SPICE models. Several examples of poor vendor supplied models and modeling pitfalls are included.
SPICE Conversions - HSPICE, PSpice, LTspice, IsSpice

A collection of syntax conversions (mainly If-Then-Else statements and switches) between HSPICE, PSpice, LTspice, and IsSpice.
AEi Systems' Component Test and Model Summary

This document contains SPICE model correlations that include bench tests compared with SPICE simulation results for magnetics (88uH inductor, seven output flyback power transformer), passive and active components (tantalum capacitors, 2N6059 BJT, IRHNM57110 FET), and various regulators (LM120/LM140). This report gives a good indication of AEi Systems' ability to accurately model components and ICs.
PSpice Modeling For WCCA

Simulation and analysis of analog circuits is normally addressed using three basic tools: a SPICE simulator, a mathematical analysis package, and Microsoft Excel. This article discuses some of the pitfalls with using PSpice and how to correct common convergence problems.
Definitive Handbook of Transistor Modeling

Techniques and Examples for modeling BJTs and Diodes. Includes Parameter definition and impact on data sheet curves.
SPICE Model Supports LDO Regulator Designs

SPICE models of power MOSFETs may prove inadequate in applications such as low dropout regulator designs. This article identifies shortcomings and defines an improved SPICE model. The new model is used to simulate results, which are then compared with measurements made from a prototype built for that purpose.
An Improved SPICE Capacitor Model

In the world of power conversion, not all capacitors are created equal. In many circuits, the characteristics of the capacitors dominate the performance of the circuit.
An Improved Mosfet Spice Model

During a recent design of a Low Dropout Voltage Regulator (LDO), using a power Mosfet as the series pass element, it became clear that there is a basic inadequacy in many of the Mosfet SPICE models that are provided by the Mosfet manufacturers and included in the SPICE simulator libraries. This paper highlights these inadequacies and also defines an improved model. This new model is used to simulate results, which are then compared with measurements made from a prototype built for that purpose.
SPICE Compatible Core Model

A magnetic core model has three major elements: permeability, hysteresis, and core loss. Unfortunately, both the permeability and the core loss are nonlinear functions. The models in this paper properly represent the non-linear permeability and the hysteresis.
SPICE Accurately Models Zeners

Zeners seem simple, but engineers generally don't know how to characterize and properly use them. Indeed, Zener characteristics change dramatically depending on operating conditions. This article details the development of a subcircuit based Zener model.
Extracting SPICE parameters from a diode using two M3500A

We do all have multimeters, so here is my attempt at modeling a diode using two Picotest M3510A meters.
Comparing SPICE to the Bench

One of the most important aspects of circuit analysis and simulation is the resulting accuracy of the mathematical circuit representation. AEi Systems' prides itself on the time proven accuracy of our SPICE models.
Model Speeds Simulation of Complex Controller

A novel approach to SPICE modeling of a two-phase synchronous step-down controller shortens startup simulation runtime from hours to minutes. Developing a SPICE model for National Semiconductor's LM2642 presents some significant challenges. This device, a two-phase, two-output synchronous step-down controller, is complex and contains a sophisticated soft-start, as well as several control loops, multiple channels and an internal clocking scheme that forces the SPICE time step to remain in the nanosecond region.
Non-Linear Saturable Kool Mu Core Model

Iron Powder cores have been well suited for applications such as switching regulator inductors, in-line noise filters, and flyback converter transformers, where high flux density capacity is the key characteristic in the magnetic core performance. This article details the development of a nonlinear core model.
Minerr function aids SPICE modeling

Almost any SPICE package employs model statements to describe elements it considers primitives. Yet generating a SPICE model for even a simple device becomes quite complex due to the number of variables that describe a typical component. However, you can simplify the process by tapping into the functionality of a general-purpose scientific analysis package like Mathcad.