gbLayout - MCM Edition

This page provides the latest online Help information for the MCM-specific featoures of gbLayout. Information on the basic operation of gbLayout is not covered on this page.

Overview	Toolbar	Parts Library	MCM Design Features
Results TextBox	Materials Library	Data Dialog

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Overview

Once a parts list has been entered, and a layout generated a user need only press the "3D" button on the top toolbar to see a 3D image of the layout. Then, to see the MCM just press the "MCM" button, which is one of 3 buttons provided to work with MCMs. Here's an image of just the 3 MCM buttons found on the lower toolbar (3D mode).

Pressing the "MCM" button will generate a 3D design, using the current 3D design properties.

Here is an image of gbLayout, with the 3D image of an MCM displayed.

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MCM Design Features

The image below show the basic design features of an MCM, including the terminology used throughout these Help pages.

gbLayout supports the following MCM design variations:

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Toolbar

There are 3 buttons on the gbLayout 3D toolbar which provide the MCM-specific features:

Here's a description of what each button does.

Display MCM	Show the 3D image of the MCM
Display Material Library	Open the materials library file (using Notepad)
Display MCM Properties Dialog	Open a dialog containing all MCM properties

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Parts Library

The parts library used by gbLayout is simply a text file ("parts.txt"), with one line per part containing the following the following information. Separate part properties with a comma.

Here's a description of the properties for each part in the library.

Description	text description, used for finding a part within the part library (20 character limit)
x	left-right width of the part
y	top-bottom dimension of the part
z	thickness of the part (extending out of the screen)
xKeepout	area unavailable for parts placement on both left and right sides of the part
yKeepout	area unavailable for parts placement at the top and bottom of the part
Color	Color used to display the part (color name or hexadecimal format)
Power	Power dissipation
I/O	Number of electrical contacts on the part's surface
Thermal Conductivity	W/C-in
Density	gm/in3

To edit the parts library, click on the "Parts Library" label to open the file in Notepad. Make any changes/additions required and then save the file.

Lines which begin with an apostrophe are ignored.

You must restart gbLayout for the changes to be reflected in the Parts Library list of gbLayout.

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Results

One the MCM is displayed, and anytime changes are made to its properties, the "Results" textbox will contain information about the information design, including the results of weight and thermal analysis of the MCM.

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Material Library

A default file called "materials.txt" is created by gbLayout. It contains a list of materials and their properites. The file may be edited by the user to add or remove parts.

The file contains one line per material. Each line contains a description, thermal density (W/C-in), and density (gm/in3). Separate each property with a comma.

Lines starting with an apostrophe are ignored.

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MCM Design Dialog

There are approximately 50 design properties a user may set to define the design of an MCM within gbLayout. All are set from the MCM Design Dialog, which can be displayed using the "Setup" button on the 3D toolbar.

The following diagram shows where the properites are used in the design of the MCM.

Here's a listing of all MCM properties:

Package Type

Interconnect	Dropdown - selection limited to "Intergrated" or "Drop-In"
Interface	Dropdown - seleciton limited to "Leads", "Pads", or "BGA"

Package Outline

Minimum Size	Specifies maximum width (x dimension) of MCM design
Fixed Size	Specifies exact height/width for MCM design
Minimum I/O	Specifies that the MCM must contain at least this many I/O

Package Elements

Base Thickness	Thickness of package base
Seal Ring Width	Width of seal ring
Seal Ring Keepout	Space on either side of the seal ring
Assembly Keepout	Space on the inside of the seal ring and outside of the substrate
Dropin Keepout	Space surrounding the substrate
Lead Ledge Width	Space around perimiter of package for lead attachement
Package Material	Material from which the package is made
Seal Ring Material	Material from which the seal ring is made

Substrate/Interconnect

Substrate Thickness	Thickness of the drop-in substrate
Substrate Material	Material from which the substrate is made
Interconnect Thickness	Thickness of the multilayer interconnect
Interconnect Material	Material from which the interconnect is made

Lid

Thickness	Thickness of the lid
Keepout	Gap between the tallest part and the bottom of the lid
Material	Material from which the lid is made
Display Lid	Directs gbLayout to display/hide the lid in the 3D image

Leads

Pitch	Lead-to-lead distance
Length	Length of lead extending beyond the package
Width	Width of an individual lead
Thickness	Thickness of an individual led
	Material from which the leads are made

Perimeter Pads

Pitch	Pad-to-pad distance
Length	Length of perimeter pad
Width	Width of perimeter pad
Thickness	Thickness of perimeter pad

Solder Balls

Pitch	BGA pad-to-pad distance
Size	Dimensions of solder balls (square)
Thickness	Thickness of solder placed on BGA pads

Thermal Model

Part Attach Thickness	Thickness of material used to attach part to interconnect
Package Attach Thickness	Thickness of material used to attach package to a PWB
Substrate Attach Thickness	Thickness of material used to attach substrate to package
Part Attach Material	Material used to attach part to interconnect
Substrate Attach Material	Material used to attach substrate to package
Package Attach Material	Material used to attach package to PWB

Colors

Package	Color of package in 3D image
Substrate	Color of substrate in 3D image
Seal Ring Support	Color of sear ring support in 3D image
Seal Ring	Color of seal ring in 3D image
Lid	Color of lid in 3D image
Leads	Color of leads in 3D image
Pads	Color of perimeter pads in 3D image
Solder Balls	Color of soldler balls in 3D image