Introduction to The Layout Environment

Microwave Office Training

Introduction to The Layout Environment

MWO Layout

Schematic View

Circuit

External World

Need Export Mapping

Schematic Layout View

Two views of the same circuit! - including connectivity (ratslines)

Note: Two different layout environments - This is the most misunderstood concept in layout!

Need Cell Faces or Cell Pins

External World

?GDSII

Artwork Cells

?DXF

"Dumb" Polygons - no notion of connectivity

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Introduction to Layout

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Modeling and Drawing Layers

We need to understand how this works

Parameterized Layout Cell

Model Layers

Drawing Layers

GDS File Layers

Line Type

2

1

User Drawn Shape

Artwork Cell Transistor with associated Artwork Cell

EM Layers

NO SCHEMATIC LINK

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Introduction to Layout

Drawing Layers

Start with Drawing Layers

Parameterized Layout Cell

Model Layers

Drawing Layers

GDS File Layers

Line Type

2

1

User Drawn Shape

Artwork Cell Transistor with associated Artwork Cell

EM Layers

NO SCHEMATIC LINK

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Introduction to Layout

2

Drawing Layers - 2

Drawing Layers The rule is: If you "see" it - it's a drawing layer.

Schematic Layout View

Artwork Cells

2

1

We can control: ? The number of layers and Names ?The order they are drawn ?Color, Line, Fill Pattern

This is setup in the LPF (layout process file). - Can work directly with the file (ASCII) - or work with most of it through the UI (recommended)

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Introduction to Layout

The LPF File

? The Layout Process File

? Units, Layout Resolution,...

Every Project has an LPF File

? Layers: Names, Colors, Patterns,...

? Model Mapping Files

? PCells: Transmission Lines, Via, ...

? User Interface (UI) in the Software

? Easier to work in the UI

? Can do everything but PCell setup

? Can see colors, patterns,...

? Can work directly with file

? Can copy between different projects

? We'll focus on this when looking at lines and vias

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Introduction to Layout

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The LPF File - Units

Under Project Options

Can also set in: Options > Project Options > Global Units

Tip - Don't Change Units After Starting a Project! (Otherwise - all your lengths will be odd numbers.)

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Introduction to Layout

The LPF File - Database and Layout Resolution

? Database Resolution

? All shapes are stored internally in nm ? Can't make shape smaller than this

? For English Units - mils ? Converts using 25.4 microns / mil ? Don't go below 0.01 mils - or will lose precision

? Layout Resolution

? Grid Spacing ? For Snapping, etc.

? Resolution ? Smallest non-zero distance ? Tip - Set to ? the process tolerance

? Export Issues Later

Set in: Options > Layout Options > Layout

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Introduction to Layout

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Example Board Stackup

Let's work with this Library ?FR4 - Epsr = 3.38, tand = .003 @ 1 GHz

?Conductors - Copper, Thickness = 1.4 mil

?Dielectric Layers - 25 mil thick

Via Layers

Dielectric Layers Metal Layers

Microstrip

AWR_Top_Copper

AWR_Via12

AWR_PCB1

Ground and Coplanar Lines

Stripline

AWR_Via23

AWR_PCB2

AWR_Mid_Ground AWR_Mid_Copper

Ground

AWR_Via34

AWR_PCB3 AWR_Bottom_Ground

Tip: Use easy to identify names! (These all have AWR_ in front of them.) Helps when layers are added.

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Introduction to Layout

A New Project with a Library

Step 1: Create a new project - importing the AWR_4Layer_PCB library.

Browse for the file: pcb_template/4layerPCB.ini

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Introduction to Layout

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