• The scaling of CMOS technology is reaching its limits. New technologies are being

studied to overcome CMOS limitations.

• Among various emerging technologies, Nano Magnetic Logic (NML) is the one that may

represent, in future, a replacement of CMOS for many reasons.

• In NML technology logic `1' and `0' are encoded inside the magnetization vector of

particularly shaped magnets.

• These technologies need a completely different design approach compared to standard

CMOS. The main logic gate for both the magnetic technologies is the Majority Voter (MV)

Research context and motivation

• Perpendicular NML (pNML): the

magnetization vector is perpendicular to

the magnets.

• A global sinusoidal clock signal is

applied to the whole circuit.

• Since the clock is global, the Artificial

Nucleation Center (ANC) is used to

determine information direction

• In-plane NML (iNML): the magnetization

vector lies in the same plane of the

magnets.

• A three phases clock mechanism is

needed to guarantee information

propagation.

• Clock zones width is limited to maximum

five elements to avoid propagation

errors.

Design of CAD Tools for Emerging Technologies

Umberto Garlando

Supervisor: Prof. Maurizio Zamboni

Submitted and published works• Turvani, G., Riente, F., Cairo, F., Vacca, M., Garlando, U., Zamboni, M., and Graziano, M. (2017) Efficient and reliable fault

analysis methodology for nanomagnetic circuits. Int. J. Circ. Theor. Appl., 45: 660–680.

• G.Causapruno, U. Garlando, F. Cairo, M. Zamboni and M. Graziano, "A Reconfigurable Array Architecture for NML," 2016

IEEE Computer Society Annual Symposium on VLSI (ISVLSI), Pittsburgh, PA, 2016, pp. 99-104.

• M.Bollo, G. Santoro, U. Garlando and M. Zamboni, "NANOcom: A Mosaic Approach for nanoelectronic circuits design," 2017

12th International Conference on Design&Technology of Integrated Systems In Nanoscale Era(DTIS), Mallorca, 2017, pp. 1-6.

• A.Ferrara, U. Garlando, L. Gnoli, G. Santoro and M. Zamboni, "3D design of a pNML random access memory," 2017 13th

Conference on Ph.D. Research in Microelectronics and Electronics (PRIME), Giardini Naxos, 2017, pp. 5-8.

• F. Riente, U. Garlando, G. Turvani, M. Vacca, M. Ruo Roch, M. Graziano, MagCAD: A Tool for the Design of 3D Magnetic

Circuits

List of attended classes• 01MNFIU – Parallel and distributed computing (19/07/2017, 5 CFU)

• 01QTGIU – Advanced techniques for highly reliable electronic system design

(04/11/2016, 4 CFU)

• 01QSCIU – Reconfigurable computing (20/07/2017, 4 CFU)

• 01RZHIU – 3D Integration: Challenges and Solutions (01/06/2017, 4 CFU)

• 02RHQRV – Intellectual Property Rights, Technology Transfer and Hi-tech

Entrepreneurship (17/07/2017, 9 CFU)

Novel contributions• MagCAD: a powerful and user friendly editor for circuits based on emerging technologies.

• iNML and pNML technologies are fully supported.

• Completely developed in C++ and multiplatform.

• The design phase consists in a simple drag&drop of the basic elements inside the

drawing windows.

• Advanced features:

1. Snap-to-grid

2. Collision avoidance

3. 3D design

4. Hierarchical design

5. Component export and import

6. Layout as images export (png, svg, jpg and pdf)

• The main feature is the automatic generation of VHDL code based on the circuit layout.

• Technological specific inspection algorithms are used to generate a structural description.

• Interconnections and signals are automatically added by the tool.

• Technological parameter can be modified by the user

• Testbench template provided among the VHDL files.

• Simulations can be performed using a standard VHDL simulator like ModelSim®.

• A technological library with a behavioral description of the basic elements is provided.

Addressed research questions/problems

Adopted methodologies• Study and research of the key aspect of the technology.

• Development of the graphic elements and the GUI.

• Set-up of the technology library for VHDL simulation.

• Write the automatic generation algorithm for VHDL description.

Future work• Include support also for MolecularQCA technology.

• Develop a general algorithm for the simulation of field coupled devices. This algorithm

is a starting point for a fast simulator for magnetic and molecular technology.

• Continue improving MagCAD performance, taking advantage of user feedbacks.

PhD program in

Electrical, Electronics and

Communications Engineering

XXXII Cycle

Logic "1" Logic "0"Logic "1" Logic "0"

Information propagation direction

ANC

MV

AB

C

OUT

A 0 0 0 0 1 1 1 1

B 0 0 1 1 0 0 1 1

C 0 1 0 1 0 1 0 1

OUT 0 0 0 1 0 1 1 1

External SimulatorOutputsMAGCAD

Circuit Design

Technology

Library

Timing

Parameters

VHDL NetlistVHDL

GenerationCircuit Design

VHDL

Generation

• No commercial tools are available in the

market for design and simulation of

circuits based on emerging technologies.

• My research activity tries to overcome this

situation, providing the possibility of fast

prototyping and simulation of digital

circuit based on magnetic technologies.

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