lecture 8- introduction to cad lecture 8- introduction to cad dr. mohamed refky amin electronics and...

Lecture 8- Introduction to CAD

Dr. Mohamed Refky Amin

Electronics and Electrical Communications Engineering Department (EECE)

Cairo University

elc.n112.eng@gmail.com

http://scholar.cu.edu.eg/refky/

Outline of this Lecture

• Previously on ELCN321

• Computer Aided Design

• L-Edit

• Layout of an inverter

Dr. Mohamed Refky

Previously on ELCN321

Dr. Mohamed Refky

Layout Design Rules

Previously on ELCN321

Dr. Mohamed Refky

Layout Design Rules

Previously on ELCN321

Dr. Mohamed Refky

Layout Design Rules

Previously on ELCN321

Stick diagrams are easy and fast way for the designers to plan

cells and estimate area before committing to a full layout.

Dr. Mohamed Refky

Stick Diagrams

Computer Aided Design

Computer aided design (CAD) is the use of computer systems (or

workstations) to aid in the creation, modification, analysis, or

optimization of a design.

CAD software is used to increase the productivity of the designer

and improve the quality of design

Electronic design automation (EDA) is a category of CAD tools

for designing electronic systems such as integrated circuits and

printed circuit boards. Since a modern semiconductor chip can

have billions of components, EDA tools are essential for their

design.

Dr. Mohamed Refky

Definition

Computer Aided Design

Since a modern semiconductor chip can have billions of

components, EDA tools are essential for their design.

Example of the CAD companies are: Cadence, Mentor Graphics

Synopsis, and Tanner.

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Definition

L-Edit

L-Edit is an integrated circuit layout toolfrom Tanner used to draw twodimensional geometry of the masks usedto fabricate an integrated circuit.

Different layers are represented bydifferent colors and patterns.

Manufacturing constraints can be definedin L-Edit as design rules.

L-Edit files are saved as file_name.tdb(Tanner Database).

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Definition

L-Edit

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L-Edit Modules

L-Edit

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L-Edit Main WindowMenu Bar

Toolbars

Layer

Palette

Mouse

Buttons

Drawing

windows

L-Edit

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L-Edit Toolbars

New

Save

OpenPrint

Cut

Copy

Paste

Undo

Redo

Find

Zoom

Hierarchy

Level

Open

Cell

Copy

Cell

User

Guide

Duplicate

Rotate

Horizontal

Flip

Vertical Flip

Nibble

Horizontal

Slice

Vertical

Slice

Merge

Group

Ungroup

DRC

Extract

L-Edit

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L-Edit Toolbars

Select

Polygon

(90o)

Rectangular

BoxPolygon

(45o)

Polygon

(all angle)

Wire Width

Wire

(90o)

Wire

(45o)

Wire

(all angle) Circle

Arc

Torus

Port

Ruler

(90o)

Ruler

(45o)

Ruler

(all angle)

Instance

L-Edit

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Setting Technology File

C:\Documents and Settings\Owner\My Documents\Tanner EDA\Tanner

Toolsv15.0\Process\MOSIS_Scalable_HP_500nm\MOSIS_Scalable_HP_500nmTec

h\mhp_n05.tdb

L-Edit

Dr. Mohamed Refky

L-Edit

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L-Edit

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Setting Grid

L-Edit

To set grid, follow the following

steps:

Under Mouse grid: set “Mouse

snap grid” to 0.5 Lambda

Dr. Mohamed Refky

Setting Grid

L-Edit

Draw the layout of a minimum size CMOS inverter

Dr. Mohamed Refky

Example