This paper introduces an improved way of modeling switched systems like Switched-Mode-Power-Supplies (SMPS), Charge-Pumps or Brushless motor drivers using pure SystemVerilog description compatible with any event-driven simulator. The gathering of all conduction phases into a unique novel state-space model representation associated to a mapping table is proposed. A new simplified emulation of high-impedance phases - that greatly reduces the needed number of simulation points - is introduced and merged with the proposed unified representation. A general SystemVerilog modeling scheme is then derived and state-space system evaluation using a Forward-Euler method is discussed. The proposed modeling is then derived for a H-bridge buck-boost structure where all conduction phases are gathered into a single matrix which is simulated as a SystemVerilog model.

This paper presents an efficient approach to carry out Switch-Mode Power Supply (SMPS) converters at-speed verifications by means of SystemVerilog (SV) Real Number Modeling (RNM). Compared to Verilog-AMS, which is typically used for modeling, SV allows to simulate into a digital environment. So, wider coverage into the interaction between the digital control unit and the analog blocks can be obtained. The analog circuits can be modeled through the description of their high-level behavior or by means of their state-space representation. This flow has been applied to a DC-DC peak-current mode controlled buck converter, and it has been evaluated through the comparison between transistor-level SPICE and SV closed-loop simulations. The implemented model shows a high level of accuracy and reduced simulation time, thus allowing for an increase in the digital verification effectiveness.

In this paper, we present a novel and unified small-signal modeling technique for Pulse-Width Modulated (PWM) DC-DC Buck converters with Ripple-Based Constant On-Time (RBCOT) control. In fact, despite the spread of RBCOT-based converters in several applications requiring tight dynamic performances and a low architectural complexity, their description through small-signal models is not always as reliable as that of fixed-frequency PWM control architectures, and a general and exact modeling framework is not well established. The proposed methodology is grounded on the DC-DC converter state-space representation and thus, differently from other modeling techniques, it permits to fully characterize the dynamic behavior of generic RBCOT converter topologies with arbitrary complex power stage and ripple injection networks. As a case study, we derive the small-signal model for a Buck converter embedding a widely used ripple injection network in industrial applications. The validity of the theoretical results is confirmed through direct comparison with SIMetrix/SIMPLIS simulations and experimental measurements in practical application scenarios, confirming the accuracy of the model even well beyond the converter switching frequency.

We investigate here both from a theoretical and practical point of view the problem of optimizing EMI reduction by means of spread spectrum clocking when lower harmonics need to be analyzed with a smaller RBW, and higher harmonics with a larger one. This situation is indeed a trade-off, where a designer can trade performance in terms of EMI reduction for lower harmonics with that achieved for higher harmonics. Two approaches are considered and analyzed. The first trade-off, denoted as Single Triangular Modulation, consists in the standard and commonly adopted triangular based spreading, where the role of the parameters is investigated with the aim of optimizing EMI reduction both in the lower part and the upper part of the spectrum. The second one, denoted as Double Triangular Modulation, is inspired by a recent Application Note and it is much more complex from an implementation point of view, being based on two simultaneous triangular modulations with different parameters. The comparison shows very similar performance, so that the adoption of the more complex approach results questionable.

In this paper we provide an improved small-signal equivalent circuit model of a synchronous Buck converter which operates in Continuous Conduction Mode (CCM) and includes an alternative Zero Voltage Switching (ZVS) mechanism for the low-side power MOSFET that rely on the MOSFETs output capacitance. The addressed analysis improves the state of the art in DC/DC small-signal modeling as it is capable to predict unexpected effects on the dynamical system response such as the dependency on input voltage introduced by parasitics. Therefore, a complete design tool which permits to evaluate the impact of the MOSFETs output capacitance and the ZVS network on the converter dynamics is proposed. The derived equivalent circuit model which includes an additional feedforward path and a feedback loop is analyzed and the main open-loop transfer functions (control-to-output, line-to-output, output impedance) are analytically assessed. A verification has been carried out through SIMPLIS circuital simulations, corroborating the validity of the whole evaluation process.

In this work, the implementation of a compact electro-thermal model of a trench gate field-stop IGBT device is presented. The primary target is to address system-level mixed signal multi-domain simulation where the simulation time is a key factor for the usefulness of results. The methodology adopted provides a model suitable for use on both SPICE-only simulators, where thermal behavior is mapped to electrical quantities, and on a multi-domain environment, where heterogeneous physical domains are managed by a simulation engine. A comparison with real device characteristics is presented to show model accuracy and finally a simulation of an inverter circuit is investigated to highlight achievable performances.