The simulator was developed at the University of California, Berkeley, and was first released in 1972. Many scientists at Berkeley and other institutions contributed to the development and improvement in subsequent versions of SPICE. In 1975, Nagel described the next major release of SPICE, called SPICE2. The core of the program still remained intact, even after many improvements and additions. These included improved device models, numerical techniques, and user interfaces. The last major release, SPICE3, came in 1985 with a conversion of the source code from FORTRAN to the C programming language. The Berkeley version of SPICE is a public domain program, but since the late 1970s a number of companies have released commercial versions of SPICE, providing further improvements in user support, in user interfaces, and, in certain cases, also in models and in simulation convergence.
AIM-Spice is a new version of SPICE running under the Microsoft Windows and Linux operating systems. AIM-Spice for Windows is capable of displaying graphically the results of a simulation in progress, a feature that allows the operator to terminate a run based on an instant information on intermediate simulation results. The development of AIM-Spice was motivated by the need of a more user friendly interface, and as a vehicle for the new set of advanced device models for circuit simulation developed by our group.
AIM-Spice Features
*AIM-Spice runs on the Microsoft Windows and Linux operating systems.
*Uses the Berkeley SPICE version 3.E1 as the kernel.
*Displays simulation results in progress by plotting graphically circuit variables during a run.
*Includes advanced new models for a number of semiconductor devices.
*Includes a graphical post processor, AIM-Postprocessor.
Simulation Control
In AIM-Spice for Windows the operator has complete control during a simulation. Before a simulation starts, the circuit variables to be monitored during the run are selected, and AIM-Spice will display graphically the progress of these variables during the simulation. The figure below shows a typical snapshot of an AIM-Spice simulation in progress.
New Semiconductor Device Models
New advanced models for the following semiconductor devices are implemented in AIM-Spice:
* Heterostructure Diode
* Heterojunction Bipolar Transistor (HBT)
* MOSFETs. The following MOSFET models are included:
o Level 1,2, 3 and 6 from Berkeley
o BSIM1
o BSIM2
o BSIM3v2
o BSIM3v3.1
o BSIM3v3.2
o BSIM3 SOI
o BSIM4 versions 1.0, 2.0, 2.1, 3.0, 4.0, 5.0 and 6.0.
* GaAs MESFETs and HFETs.
* Amorphous Silicon Thin Film Transistors (a-Si TFTs)
* Polysilicon Thin Film Transistors (poly-Si TFTs)
The FET models are all based on versions of the unified charge control model (UCCM), which describes the channel charge in Field Effect Transistors (FETs) in the above and below threshold regimes, using one analytical expression.
Extensions to Berkely SPICE:
* Temperature sweep analysis
* Support for libraries
* Libraries containing thousands of devices
* Support for parameters in the netlist
* Support for parameters in subcircuit calls
* Polynomial dependent sources (POLY sources)
* Global nodes
* BSIM3 versions 2 and 3 ((MOSFET levels 13 and 14)
BSIM4 versions 1.0, 2.0, 2.1, 3.0 and 4.0.
* Support for extended commands:
.connect
.defwave
.global
.lib
.param
.plot
* Enhanced commenting features (comment blocks and comments within continuation lines)
AIM-Postprocessor
A graphic postprocessor is included in the AIM-Spice simulator package. This application, like AIM-Spice, runs under the Microsoft Windows environment.
Although AIM-Spice has facilities to plot circuit variables graphically, AIM-Postprocessor has a much more powerful plotting engine including the following features:
* Plotting of sums and differences, derivatives, integrals, and mathematical functions of circuit variables and creating hard copies.
* FFT (Fast Fourier Transform)
* Cursors to select numerical values and to calculate differences between variables.
* Import of experimental data.
* Hard copies
