### Circuit simulator for Jupiter ACE

Full title | SPICE |

Year of release | 2016 |

Publisher | Prof. DR. Samir Ribić at University of Sarajevo |

Producer / Author(s) | Prof. DR. Samir Ribić at University of Sarajevo |

Memory | 51K |

Type | Utility |

Cost : | PD |

Download | Spice
[CRC32 503A0CF8] Distribution Permission Allowed | Group 1 |

### Loading Instructions

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### Instructions

SPICE

SPICE is a general-purpose circuit simulation program for nonlinear dc, nonlinear transient, and linear ac analyses. As
an early public domain software program with source code available, SPICE was widely distributed and used. Its
ubiquity became such that "to SPICE a circuit" remains synonymous with circuit simulation. SPICE source code was
from the beginning distributed by UC Berkeley for a nominal charge (to cover the cost of magnetic tape). It was in
widespread use on VMS and Unix mainframes, and later on PC computers in education, industry and military.

SPECI-SPICE

Although SPICE has roots in 1973, it was not available on personal computers until commercial PSPICE in 1984 for
IBM PC. The home computers from 8 bit computer era (CP/M, Apple II, ZX Spectrum, C64 ...), but also some early 16
bit computers (IBM PC with less than 512K, Commodore Amiga 1000, Texas Instruments TI89) were considered too
weak to host SPICE. The free version was not available for PC computers until 386 age. Also, its source code written in
Fortran and converted to C is not easy to understand.

Phenomena of emulators and cross developmment tools revived the interest on old home computers, so why not
implement electric circuit simulator like SPICE on them, too? There will be some restrictions, but it is said that 10% of
program code does 90% of job. With some model simplifications, restriction to node naming, and omiting some
analyses like temperature, Fourier, noise and TF, we can implement most of SPICE functionality in a very limited 8 bit
computers memory.

SPECI-SPICE is implementation of SPICE2 subset for 8 bit Z80 computers. It supports all 16 devices available in
SPICE2 and four major analyses (OP, DC, AC and TRAN). As it is written in standard C, it can be also recompiled to
Unix, MS Windows and MS DOS systems.

SPECI-SPICE is a general-purpose circuit simulation program for nonlinear dc, nonlinear transient, and linear ac
analyses. Circuits may contain resistors, capacitors, inductors, mutual inductors, independent voltage and
current sources, four types of dependent sources, and the four most common semiconductor devices: diodes, BJT’s,
JFET’s, and MOSFET’s.

SPECI-SPICE has built-in models for the semiconductor devices, and the user need specify only the pertinent model
parameter values. The model for the BJT Ebers-Moll model. The diode model can be used for either junction diodes or
Schottky barrier diodes. The JFET model is based on the FET model of Shichman and Hodges. MOSFET is described
by a square-law I-V characteristic

TYPES OF ANALYSIS

DC Analysis

The dc analysis portion of SPECI-SPICE determines the dc operating point of the circuit with inductors shorted and
capacitors opened. A dc analysis is automatically performed prior to a transient analysis to determine the transient
initial conditions, and prior to an ac small-signal analysis to determine the linearized, small-signal models for non-linear
devices

AC Small-Signal Analysis

The ac small-signal portion of SPECI-SPICE computes the ac output variables as a function of frequency. The pro
gram first computes the dc operating point of the circuit and determines linearized, small-signal models for all of the
nonlinear devices in the circuit. The resultant linear circuit is then analyzed over a user-specified range of frequencies.
The desired output of an ac small- signal analysis is usually a transfer function (voltage gain, transimpedance, etc

Transient Analysis

The transient analysis portion of SPECI-SPICE computes the transient output variables as a function of time over a
user-specified time interval. The initial conditions are automatically determined by a dc analysis. All sources which are
not time dependent (for example, power supplies) are set to their dc value.

Full instructions can be found in the PDF and further information here