Cad Tools For Vlsi Design And Simulation

The VLSI group is active in developing Computer Aided Design tools and flow to help to analyse and designing complex circuits based on both Ultra Deep Submicron and emerging beyond CMOS technologies. In the following, a short introduction to TAMTAMS, ToPoliNano, ToMoDuCK, and MoSQUiTo is given. Follow then the links to get more detailed information on each of them as well as to download the available files.

ToPoliNano and MagCAD

Website: https://topolinano.polito.it/

ToPoliNano (TOrino POLItecnico NANOtechnology) is a multi-platform CAD framework developed by the VLSI group of Politecnico di Torino. The project has grown around the idea of creating a flexible tool able to design, simulate and test circuits based on emerging nanotechnologies.

ToPoliNano (TPN) is a synthesis and simulation tool for emerging technologies. Starting from a VHDL description, automatic place and route algorithms are able to generate a circuit based on the selected technology. After that, a simulation can be performed providing input stimuli through a testbench.

MagCAD is intended as a graphical editor for the TPN framework. Users can design custom circuit through a user-friendly GUI. The designed circuits can be exported as components for later use. Furthermore, a VHDL description of the circuits can be automatically exported by the tool: these VHDL netlists can be simulated with a standard logic simulator, like ModelSIM .

A technological library is also provided to perform simulations.

Both TPN and MagCAD are fully developed in C++ and the Qt Framework has been adopted to operate across Linux, Mac OS and Windows.

Currently, the ToPoliNano framework fully supports in-plane Nano Magnetic Logic (iNML) technology. The two workflows can be mixed thanks to files import/export. Circuits designed with MagCAD can be used as custom components in ToPoliNano. Indeed, the custom circuits can be directly instantiated within the VHDL description.

In addition, automatic-generated layouts generated by ToPoliNano can be re-opened and modified by using MagCAD. Furthermore, users can select among the two different simulation paradigm (TPN embedded simulator or external VHDL simulation after automatic generation).

ToPoliNano supported technologies:

in-plane Nano Magnetic Logic (iNML)

MagCAD supported technologies:

in-plane Nano Magnetic Logic (iNML)
perpendicular Nano Magnetic Logic (pNML)

We are working to add full support for pNML technology and to add support for other emerging technologies. Both tools are distributed under free license and can be downloaded from here.

TAMTAMS (Torino Assesment of Mos Technology and Advanced perforMance of System calculator)

Website: https://tamtams.vlsilab.polito.it/

Ultra Deep Sub-Micron (UDSM) processes, as well as beyond CMOS technology choices, influence circuits performance with a chain of consequences through devices, circuits, and systems that are difficult to predict. Nonetheless, effective design-space exploration enables process optimization and early design organization. TAMTAMS is a web-based tool organized as an open, flexible and simple structure, which allows predicting system-level features starting from technology variables. It is modular and based on a clear dependency tree of modules, each related to a model of specific quantities (e.g. device currents, circuit delay, interconnects noise, ….) presented in up-to-date papers in the literature. Models can be compared and sensitivity to parameters observed. For the device engineer, as well as for the circuit and systems designer using TAMTAMS gives a fresh point of view on process-to-system predictors. Though still in development, it already shows flexibility and allows a traceable path of a technology parameter on its way to the system level.

ToMoDuCK (Torino Molecular conDuction quiCK simulator)

The scaling down of CMOS technology is approaching to its physical and technological limits. This makes it essential to explore novel ideas and alternative technologies for the continued miniaturization of electronic devices and electronic circuits. Molecular devices are a good approach for highly dense and low power future computing applications. However, the detailed physical and chemical based description of current as a function of voltage is computationally complex. The complexity increases with the number of devices combined in interconnected functional structure. Unlike molecular electronics, CMOS technology allows a circuit designer to efficiently simulate complex circuits due to the availability of hierarchy of interconnect and device models of varying accuracies. Thus, in order to explore the potentials of molecular electronic devices as an alternative technology, efficient simulation methodologies are needed, especially when circuits of reasonable complexity have to be analyzed.
TOMODUCK then has two main goals: 1) To improves the state of the art in term of computational time compared to Atomistix ToolKit (ATK) and 2) To maintain a near to optimal accuracy, improved with respect to other modeling approaches. As a by-product, we demonstrate throughout the paper how the proposed model can be valuable in guiding and analyzing the physics of molecular transistors, as a precursor of a wide variety of complex molecular electronic applications.