MacSpice 3
by Charles D. H. Williams
Introduction
MacSpice simulates and analyses electronic circuits that can range in complexity from a single resistor to an integrated circuit comprising tens-of-thousands of devices. It has users who range in experience from novices to retired integrated circuit designers. It is used at various universities internationally for research and teaching.
MacSpice 3.2 runs natively on Mac computers with 64-bit Intel or Apple silicon processors. It is compatible with, Berkeley Spice 3f5 but incorporates many improvements to Spice 3f5 – from simple bug-fixes to entirely new commands, algorithms and solution strategies. For example: the memory leaks that affected Spice 3f5 have been cured; new algorithms have been developed to facilitate the simulation of large circuits, and to reduce simulation time; MacSpice provides a robust multi-parameter optimizer and facilities for inter-process communication with other applications.
What MacSpice Does
Circuit simulation is a way of building and testing virtual models of electronic devices. It is usually cheaper and quicker to simulate a design than to build a prototype. MacSpice requires a text-file description of the circuit as input. This 'netlist' is a list of components and the nodes they connect to. Users may prepare netlists with a text editor, or derive them from a circuit diagram using a third-party schematic-capture application. MacSpice then builds a numerical model of the circuit and analyses this.
A command interpreter (shell) is used to specify the types of analyses that are required and how the results should be processed, saved or displayed. The high quality of the MacSpice command interpreter makes the automation of tasks straightforward.
Simulation is a tool, not a magic-wand. The quality of the results depends on the accuracy of the netlist and the device models used. Within Spice most devices are ideal – its resistor, for example, has just one property: resistance. A real resistor has parasitic inductance and capacitance; if these have a significant influence on the circuit, they must be added explicitly to the netlist.
Learn to Use MacSpice
MacSpice helps the user by providing error messages, warnings and explanatory notes. Users will, however, need to supplement these with following reference and training and information:
- New Spice User:
- New MacSpice User:
- Experienced MacSpice User:
Trademarks
Intel is a registered trademark of Intel Corporation. Mac and the Mac logo are trademarks of Apple Computer, Inc., registered in the U.S. and other countries. PowerPC is a trademark of International Business Machines Corporation.