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SPICE Model <What is SPICE?>

SPICE is open-source software that simulates the operating conditions of analog circuits. It is short for 'Simulation Program with Integrated Circuit Emphasis'.

History of SPICE

Developed by the University of California, Berkeley in 1973, SPICE has undergone changes as shown in the table below to reach its current format.

The first version, SPICE1, was coded in FORTRAN.

The most popular SPICE simulator is based on SPICE2G.6 and is written in C.

Year SPICE Version Language
1985 SPICE 3 C

FORTRAN is a procedural programming language developed for scientific computing.

It facilitates optimization of parallel computing operations to achieve faster processing speeds.

During this time, programs were executed on large-scale computers (mainframes).

What Can You Do With SPICE?

More specifically, it is a general-purpose circuit simulation program that provides linear AC analysis, non-linear transient analysis, and nonlinear DC analysis.

Analysis is performed by solving combinations of theoretical and experimental (device model) equations representing the behavior of elements based on Kirkhoff's current and voltage laws, utilizing modified nodal point analysis.

Device Model

A device model is an analytical expression that was developed based on theoretical and experimental study.

Elements and devices can be simulated:

  • Passive components (i.e. resistors, capacitors, inductors)
  • Active devices (e.g. diodes, bipolar transistors, MOSFETs)
  • Transmission lines
  • Power sources

Analysis methods:

  • Transient
  • DC
  • Small-signal AC
  • Noise

Until SPICE, IC design was carried out entirely by hand.

However, the switch to electronic circuit design following the advent of computers, combined with an increase in the number of elements that can be incorporated into ICs, laid the foundation for SPICE.

This was made possible due to advancements in production technology.

Incidentally, PSpice® from Cadence Design Systems is the first simulator that can be run on a PC, making the transition from requiring a mainframe.

Although initially designed as a simulator for electronic circuits, it has now become an essential tool for board design that transmits electrical signals and requires analog elements utilizing high-speed CPU operation.

  • Electronic Board Design (PSpice)
  • PCB Design/Validation (IBIS)

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