SPICE Simulators and SPICE Models


Points of this article

・Free SPICE simulator versions are provided by simulator vendors, and can be downloaded and used.

・In order to simulate circuits using ICs or other components, SPICE models for the components, which provide parameter information for the devices, are necessary.

・Many SPICE models are provided by different manufacturers for downloading from websites.

This article introduces sources for downloading SPICE-based simulators and SPICE models. It is after all best to actually run a simulator in order to come to understand it. The simulators run on general-use PCs and OSes; please give one a try.

Free SPICE Simulators

The following are vendors who provide free simulator packages, and the downloading sites. In some cases registration is required.

Name Vendor Download Site
OrCAD Cadence Design Systems Download (free)
LTSpice Analog Devices (former LTC) Download (free)
SIMetrix SIMetrix Technologies Download (free)

※The above company and product names and the like are generally trademarks or registered trademarks of their respective companies.

SPICE Models

In order to execute a simulation, the simulator software, and SPICE models (macro models) that provide parameters for the devices and elements, are necessary. SPICE models of general-use transistors, resistors, capacitors and other basic components may be included with the simulator. SPICE models of specific transistors, ICs and so on are provided on the websites of the manufacturers. Moreover, SPICE models of different manufacturers can be downloaded from the PSpice Community managed by Cadence. Also, circuit examples in which external components required by specific ICs and devices are positioned and optimized are provided by manufacturers, in the guise of evaluation circuits and demo circuits; these can be used to greatly speed up design. Nearly all evaluation circuits and demo circuits are for use with specific simulators, and so it is important to check the simulator for which the circuit is intended.

Below, details for downloading SPICE models and evaluation circuits from the ROHM website and from the PSpice Community are provided.

ROHM Website
From the main page, click on Technical Support, and then click on Design Support/Design Simulation Models.

The following page appears; upon searching on products and product categories and then clicking on the relevant part number, the SPICE model and an evaluation circuit can be downloaded. Evaluation circuits are currently intended for use with SIMetrix.

ROHM currently provides the following SPICE models.

Evaluation circuits can also be downloaded from “Reference Designs”.

Upon finding a reference circuit that matches your design, click on “Reference Document Download”. A PDF file will open; upon clicking on “SIMetrix SPICE Simulation Data File” in the file, the download will begin. The PDF file also shows simulation results. A downloaded evaluation circuit can be modified and customized.

PSpice Community
Access the PSpice Community of Cadence, and click on “Model Library”.

Next, click on “ROHM” from the selection of manufacturers. SPICE models offered by ROHM can then be downloaded.

In the next article, we will explain what is possible using SPICE.

Information on Downloading Technical Documents

Downloadable materials, including lecture materials from ROHM-sponsored seminars and a selection guide for DC-DC converters, are now available.

Download Technical Documents

Downloadable materials, including lecture materials from ROHM-sponsored seminars and a selection guide for DC-DC converters, are now available.