At Sonnet, we've been developing 3D planar high frequency EM software since 1983, and our software has earned a solid reputation as the world's most

Transcription

1 14.52 Rev 1.0

2 At Sonnet, we've been developing 3D planar high frequency EM software since 1983, and our software has earned a solid reputation as the world's most accurate commercial planar EM analysis package for single and multi-layer planar circuits, packages and antennas. Sonnet Software Inc., founded by Dr. James C. Rautio, is a private company, entirely dedicated to the development of commercial EM software. We take great pride in providing quality technical support for our products with timely response--which we believe to be very important for high-end technical software products. Sonnet is based in Syracuse, NY, USA with representatives across the globe.

3 GERBER/ODB++ TRANSLATOR Published: May 2018 Release 16 Sonnet Software, Inc. 126 N. Salina Street Syracuse, NY Phone: (315) Fax: (315) Copyright 1989,1991,1993, Sonnet Software, Inc. All Rights Reserved Registration numbers: TX , TX

4 Copyright Notice Reproduction of this document in whole or in part, without the prior express written authorization of Sonnet Software, Inc. is prohibited. Documentation and all authorized copies of documentation must remain solely in the possession of the customer at all times, and must remain at the software designated site. The customer shall not, under any circumstances, provide the documentation to any third party without prior written approval from Sonnet Software, Inc. This publication is subject to change at any time and without notice. Any suggestions for improvements in this publication or in the software it describes are welcome. Trademarks The program names, xgeom, emstatus, emvu, patvu, dxfgeo, ebridge, emgraph, gds, cvbridge, emserver, emclient, sonntcds, and sonntawr, sonntawr64, Blink, Co-calibrated, Lite, LitePlus, Level2 Basic, Level2 Silver, and Level3 Gold are trademarks of Sonnet Software, Inc. Sonnet, em, and emcluster are registered trademarks of Sonnet Software, Inc. Windows XP, Windows Vista, Windows 7, Windows 8, Windows 10 and Internet Explorer are U.S. registered trademarks of Microsoft Corporation. AutoCAD and Drawing Interchange file (DXF) are trademarks of Auto Desk, Inc. Cadence and Virtuoso are registered trademarks of Cadence Design Systems, Inc. GLOBALFOUNDRIES is a registered trademark of GlobalFoundries, Inc. Agilent, ADS, and Touchstone are trademarks of Keysight Technologies. NI AWR and Microwave Office are registered trademarks and EM Socket is a trademark of National Instruments, Inc. HSPICE is a registered trademark of Synopsys, Inc. GDSII is a trademark of Calma Company. Flexera Software, Flexlm, FlexNet, InstallShield, are trademarks of Flexera Software, Inc. and/or InstallShield Co.Inc. in the United States of America and/or other countries. OSF/Motif is a trademark of the Open Software Foundation. X Window System is a trademark of The Open Group Linux is a registered trademark of Linus Torvalds. Red Hat is a registered trademark of Red Hat, Inc. SUSE, opensuse and SLES are registered trademarks of SUSE LLC. OpenGL is a registered trademark owned by Silicon Graphics, Inc. MATLAB is a registered trademark of The MathWorks, Inc. in the United States and/or other countries. Acrobat is a registered trademark of Adobe Systems Incorporated. Xpeedic and IRIS are registered trademarks of Xpeedic Technology. ODB++ is a registered trademark of Mentor Graphics Corporation. Modelithics is a registered trademark of Modelithics, Inc.

5 Table of Contents TABLE OF CONTENTS TABLE OF CONTENTS THE SONNET BOX Coupling to the Box GERBER TRANSLATOR Converting your files to Sonnet Single Layer Import Multi-Layer Import Job File Import Layer Mapping Sonnet Stackup Gerber Importer Windowing Netex-G Stackup Drill Files Drill2Gbr Windowing Post Conversion Editing Exporting Sonnet Projects to Gerber Format Files GERBER TRANSLATOR TUTORIAL Obtaining the Translator Example Files Single Layer Translation Multi-Layer Translation Layer Mapping Drill File Windowing Job File Translation Changing Directories of Job Files ODB++ TRANSLATOR Converting your files to Sonnet ODB++ Import

6 Gerber/ODB++ Translator ODB++ Import Window APPENDIX I VIA SIMPLIFICATION Introduction Via Array Simplification Via Array Criteria Additional Simplify Via Array Options Simplify Via Array Options Minimum Vias in Array Max Distance to Size Ratio Maximum Size to Size Ratio Max Expansion Coefficient Merge Planar Polygons During Simplification. 97 Number of New Via Metals Created Simplified Via Array Loss Bar Via Group Simplification New Via Metals and Bar Via Loss INDEX

7 Chapter 1 The Sonnet Box Chapter 1 The Sonnet Box Metal Box Top The Sonnet six-sided shielding box. The metal walls of the box are transparent to allow you to see the interior of the circuit. Metal Side Walls The Sonnet EM analysis is performed inside a six-sided metal box as shown above. This box contains any number of dielectric layers which are parallel to the bottom of the box. Metal polygons may be placed on levels between any or all of the dielectric layers, and vias may be used to connect the metal polygons on one level to another. The four sidewalls of the box are lossless metal, which provide several benefits for accurate and efficient high frequency EM analysis: The box walls provide a perfect ground reference for the ports. Good ground reference is very important when you need S- 7

8 Gerber/ODB++ Translator parameter data with dynamic ranges that might exceed 50 or 60 db, and Sonnet s sidewall ground references make it possible for us to provide S-parameter dynamic range that routinely exceeds 100 db. Because of the underlying EM analysis technique, the box walls and the uniform grid allow us to use fast-fourier transforms (FFTs) to compute all circuit cross-coupling. FFTs are fast, numerically robust, and map very efficiently to computer processing. There are many circuits that are placed inside of housings, and the box walls give us a natural way to consider enclosure effects on circuit behavior. As an example, a microstrip circuit can be modeled in Sonnet by creating two dielectric layers: one which represents your substrate, and one for the air above the substrate. The metal polygons for the microstrip would be placed on the metal level between these two dielectric layers. The bottom of the box is used as the ground plane for the microstrip circuit. The top and bottom of the box may have any loss, allowing you to model ground plane loss. Coupling to the Box Since the four sidewalls of the box are lossless metal, any circuit metal which is close to these walls can couple to the walls - just like what would happen if you fabricated and measured a real circuit with the same box. If you do not want to model this coupling (for example, your real circuit does not have sidewalls), then you must keep the circuit metal far away from the box sidewalls. A good rule to use is at least three to five substrate thicknesses as shown below. This circuit has a substrate of 25 mils. The spiral should be kept at least mils from the box walls. 8

9 Chapter 1 The Sonnet Box All Sonnet geometry projects are composed of two or more dielectric layers. There is no limit to the number of dielectric layers in a Sonnet geometry project, but each layer must be composed of a single dielectric material. Metal polygons are placed at the interface between any two dielectric layers and are usually modeled as zero-thickness, but can also be modeled using Sonnet s thick metal model. Vias may also be used to connect metal polygons on one level to metal on another level. You will use the Dielectrics dialog box (Circuit Dielectric Layers), as shown below, to add dielectrics to your circuit. Each time a new dielectric layer is added, a corresponding metal level is also added to the bottom of the new dielectric layer. You may also add dielectric layers in the Stackup Manager. This example shows a 3-D drawing of a circuit (with the z-axis exaggerated). Please note that the pictured circuit is not realistic and is used only for purposes of illustrating the box setup. Note that the number of the metal level appears in between the dielectric layers. Dielectric Layer 0 1 Metal Level 2 Metal Bottom (Ground Plane). This is not shown in the Dielectric Layer dialog box Below is a glossary of some commonly used terms in Sonnet which relate to the box model. 9

10 Gerber/ODB++ Translator Dielectric Layer: This refers only to dielectrics, NOT metals. In the example above, there are four dielectric layers. There is an entry for each dielectric layer in the Dielectric Layers dialog box (Circuit Dielectric Layers). Metal Level: Metal levels are modeled as zero thickness and are attached to the dielectric layer ABOVE them. In the example above, there are three metal levels in addition to the box top and bottom. Since no metal may be placed on the top of the box, it may not be accessed by the user or viewed in the project editor. The bottom of the box is referred to as the GND level and may be accessed in the project editor. It is not labeled in the dielectric window. The top and bottom of the box are lossless metal by default, but can be changed in the Box Settings dialog box (Circuit Box Settings). You can use as many different metal types as you wish on a single metal level; for instance, you may use a silver polygon and copper polygon on the same metal level. NOTE: A layer refers to a dielectric layer while level refers to the metal level which is sandwiched between the two dielectric layers. So, technically, there is no such thing as a metal layer in Sonnet. GND Level: You can place polygons on the GND level, but they have no effect because this level is already completely metalized. However, cases do exist in which you may want to place a polygon on the GND level in order to place a via or a dielectric brick there. Viewing Levels: When you view your circuit in the normal 2D view in the project editor, you are always on a particular level, as shown by the level drop list in the Project Editor tool bar as shown below. The top level is always 0 and increases as you move downward through the box. You can switch levels by using 10

11 Chapter 1 The Sonnet Box your arrow keys, or using the level drop list. By default, all polygons on your present level are shown in Fill, and all polygons on all other levels are shown as dashed outlines. Level 0 is displayed in the level drop list in the project editor. The dotted outline indicates metal on the level below this one. Level 0 You may also change the view to other metal levels by using the Up One Level and Down One Level button on the project editor tool bar. The dotted polygon seen above is shown on Level 1 which is below Level 0. Level 1 As mentioned above, the metal level is associated with the dielectric layer above, such that when you delete a dielectric layer, the metal level directly below the layer is deleted. The total height of the box is determined by the sum of the thicknesses of the dielectric layers since metal is either modeled as zero-thickness or protrudes into the dielectric layer above. If you wish to model microstrip circuits, you will need to place a thick layer of air above your circuit; i.e., the topmost dielectric layer should be at least three to five times the substrate thickness. 11

12 Gerber/ODB++ Translator 12

13 Chapter 2 Gerber Translator Chapter 2 Gerber Translator The Gerber translator allows you to convert a single Gerber file or multiple Gerber files to a Sonnet project compatible file. Once you have converted your Gerber file(s) to a Sonnet project, you then need to adjust it using the project editor before you can analyze the circuit with em. This chapter discusses using Sonnet s project editor and assumes that the user is very familiar with the project editor. For a tutorial on using the Gerber translator, please see Chapter 3 "Gerber Translator Tutorial" on page 37. NOTE: The Gerber translator is only available if you have purchased a Gerber translator license from Sonnet. Please see your system administrator if you are unsure of the availability of this program. The Gerber Translator is only available on Windows Platforms. The Gerber translator can also be used to convert a Sonnet project to a set of Gerber files, but these files are limited to the information contained in the project. See the File Export command in the project editor s Help for details. 13

14 Gerber/ODB++ Translator Converting your files to Sonnet The Gerber translator inputs Gerber format files from a circuit layout program and converts them to a Sonnet project. The translator is accessed through the project editor. There are three different types of Gerber imports: Single Layer, Multi- Layer and Job File. Each type is discussed below. For more information on the dialog boxes used during the import, please refer to Help by searching on Gerber Translator in the index or by clicking on the Help button of any of the dialog boxes. 14

15 Chapter 2 Gerber Translator Single Layer Import The Single Layer import is used to translate a single Gerber file into a Sonnet project. The diagram below shows the import process for a Single Layer Import. Select File Import Gerber (Single Layer) from project editor main menu. Browse Window Select the input.gbr file. Import Control dialog box Specify destination project, optional template file, and set technology layers checkbox. Gerber Importer window Optionally select part of Gerber file and translate. Layer Mapping dialog box Determines mapping of Gerber file to Sonnet level, object, material and Technology Layer. Import Options dialog box Controls project length units, sets conversion standards and sets via properties. Import window Allows you to execute the Import and display conversion status. Sonnet Project Post Conversion Editing 15

16 Gerber/ODB++ Translator Multi-Layer Import The Multi-Layer import allows you to import multiple Gerber files and set the stackup so that the metal layers are arranged correctly in the Sonnet project. The stackup controls on which layers to use specific metal files, placement of dielectric layers and how to apply drill files. The diagram below shows the import process for a Multi-Layer Import. Select File Import Gerber (Multi-Layer) from project editor main menu. Import Control dialog box Specify destination project, optional template file, and set technology layers checkbox. Netex-G window Setup stackup and define vias, then translate Gerber files. Drills Optionally input drill file(s) to determine the placement of vias between metal levels. Import Options dialog box Controls project length units, sets conversion standards and sets via properties. Import window Allows you to execute the Import and display conversion status. Sonnet Project Post Conversion Editing 16

17 Chapter 2 Gerber Translator Job File Import The Job file import allows you to import multiple Gerber files using a job file to control the stackup. The job file is usually created on a previous Gerber multilayer input. This method of importing Gerber files allows you to set up the stackup once by performing a multi-layer import, then quickly re-import when you make changes to the metal layer files or drill files. The diagram below shows the import process for a Job File Import. Select File Import Gerber (Job File) from project editor main menu. Browse Window Allows to select the desired job file for the import. Import Control dialog box Specify destination project, optional template file, and set technology layers checkbox. Netex-G window Setup stackup and define vias, then translate Gerber files. Settings are filled in from the job file. Import Options dialog box Controls project length units, sets conversion standards and sets via properties. Import window Allows you to execute the Import and display conversion status. Sonnet Project Post Conversion Editing 17

18 Gerber/ODB++ Translator Layer Mapping One of the most important aspects of importing Gerber files is in mapping the Gerber files to your Sonnet project. The Gerber file does not contain the information listed below, which Sonnet requires to translate the Gerber file into a Sonnet project. In the case of a Single Layer import, this information is conveyed to Sonnet through the Layer Mapping settings. 1 The physical location of the layer (i.e., level) in the Sonnet project (i.e., the stackup) 2 The object type that the layer represents (planar metal, via, or dielectric brick) 3 The material properties of the polygons Sonnet s Technology Layers can be used to store all of this information making translations much more efficient. In the case of Multi-Layer and Job File imports, the Netex-G window is used to define Sonnet s stackup and controls how the Gerber files are mapped to Sonnet. For more information on the Netex-G window, please see Netex-G, page 21. The layer mapping can be accomplished two different ways: 1 Manually entering the information at the time of import: This is accomplished with the Layer Mapping dialog box as shown below. Oftentimes, you only need to enter this information on your first import, then a template can be used for subsequent imports. 2 Using a project file as a template: Typically, after your first import, and after setting up all your settings, you would save the file as a template project to be used for subsequent imports. When using a template file, the Layer Mapping dialog box is automatically filled in for you using information included in the template. Mapping information in your template file is stored in the Technology Layer definitions. Technology Layers allow you to define a group of 18

19 Chapter 2 Gerber Translator Sonnet Stackup objects with common properties including the metal level on which they are placed in your Sonnet project; they may also store the import/export settings for Gerber for the project. For more information on Technology Layers, please see Technology Layers in the index of Help. In order to properly map the layers in the Gerber files to the Sonnet project, you need to have an understanding of the metal levels convention in Sonnet. Below is a 3D view of a Sonnet project with two metal levels; the stackup manager for the project is also shown. Note that level 0 is the highest metal level and is attached to the bottom of the top dielectric layer. Level numbers increase as you move down through the dielectric layers. It is also important to note that Sonnet s convention is that thick metals extend upwards into the dielectric above. NOTE: The top level of your circuit is on Level 0 in the project editor. Next level below is Level 1. (See the figure below) Level 0 Level 1 GND The Project Editor Level Numbering in a 3 layer circuit. Gerber Importer Gerber Importer, which is used to perform the import for single layer files, is the program in which you may optionally select only part of the Gerber file to import using a windowing function and execute the import into Sonnet. It is also used in 19

20 Gerber/ODB++ Translator a multi-layer import for the windowing function if you wish to select part of the layers being imported. In that case, the Gerber Importer is accessed through Netex-G, discussed in the following section, and does not perform the import. Windowing When performing a single layer import, the layer which you are importing is displayed in the Gerber Importer window when it opens. If you wish to import the whole layer, click on the Import button on the tool bar. A progress window appears, and when the import is complete the progress window and the Gerber Importer window are closed. If you wish to select only part of the Gerber metal layer to import, you may do so by selecting one of the Window buttons on the tool bar. The buttons are shown below. If you wish to select a rectangular area, click on the Rectangular window button, then click and drag your mouse to select the desired area. If you wish to select an area which is a polygon, click on the Polygon Window button, then click on each vertex of the desired polygon. Double-clicking closes the polygon. In either case, once the desired area is selected, click on the Import button. Only the area enclosed is translated. Rectangular Window button Polygon Window button 20

21 Chapter 2 Gerber Translator Netex-G Netex-G, which is used for multi-layer, job file and ODB++ imports, is the program in which you set up the stackup for translation into Sonnet and execute the import. Netex-G allows you to assign Gerber files to a source layer and map that layer to the Sonnet project and select the layer type of the Gerber file. This allows you to place multiple input files in the correct order for translation. You may also access controls which allow you to translate and assign a drill file to the translation as well as a windowing function that allows you to select only part of the input layer files to be translated. For detailed information on all the settings please click on the Help button. Stackup You use the entries in the Netex-G window to define the stackup of the Gerber layer files you are importing and the placement of dielectric layers which determines where they are placed in the Sonnet project. It is important that you understand the setup of the Sonnet Box in order to correctly place your metal and dielectric layers. The Sonnet EM analysis is performed inside a six-sided metal box. This box contains any number of dielectric layers which are parallel to the bottom of the box. Metal polygons may be placed on levels between any or all of the dielectric layers, and vias may be used to connect the metal polygons on one level to 21

22 Gerber/ODB++ Translator another. The first metal layer that is specified is translated to metal Level 0 in the Sonnet project. You need to place a dielectric layer above this metal level because the Sonnet box requires that there be a dielectric (most commonly used is air) between the metal level and the box top since the box top is metal. In a similar manner, the box bottom is also metal. You should insert a dielectric layer beneath your bottom metal layer if you wish to preserve the polygons in the file. If you wish to use your bottom metal level as your ground plane, do not insert a dielectric layer below it, and that metal layer is used as the box bottom. There is always a dielectric layer between metal levels in a Sonnet project, so inserting a dielectric layer between your Gerber metal layer files causes them to be imported on separate metal levels in Sonnet. It is possible to have more than one type of metal on a metal level in a Sonnet project. If you wish to import two metal layers composed of different metals but wish to have them both appear on the same metal level in Sonnet, do not place a dielectric layer between them. The Netex-G window with the stackup complete is shown below. The Gerber file M1.gbr is assigned to Stackup layer 2 making it the topmost level of metal which in Sonnet appears on metal level 0. The dielectric layer above M1.gbr in the stackup is the dielectric layer you need between the top metal layer and the box top in Sonnet. There is another dielectric layer inserted in the Stackup layer 3 so that there is a dielectric layer between the two metal levels; Sonnet requires that there be a dielectric layer between metal levels. Gerber file M2.gbr is assigned to Stackup layer 4; this metal level appears in Sonnet on metal level 1. There is a 22

23 Chapter 2 Gerber Translator dielectric layer inserted below the M2.gbr to separate the imported metal from the box bottom. There is also a drill file specified that extends from Stackup layer 2 to Stackup layer 4 so that the vias connect the two metal levels in Sonnet. 23

24 Gerber/ODB++ Translator The imported circuit is shown below with the various elements specified in the stackup in Netex-G identified. The lower of the two views shows the circuit without the top metal level 0 for clarity. The top view shows the complete circuit. This dielectric layer (usually a layer of air) was input in Stackup Layer 1 and appears in Sonnet between the top metal level and the box top. Sonnet Level 0 M1.gbr was input in Stackup layer 2 and appears in Sonnet on metal level 0. The highlighted dielectric layer was input in Stackup layer 3 and appears in Sonnet between the two metal levels. Sonnet Level 1 M2.gbr was input in Stackup layer 4 and appears in Sonnet on metal level 1. The highlighted dielectric layer was input in Stackup layer 5 and appears in Sonnet between the bottom metal level and the box bottom. Drill Files Drill files are used to determine the placement of vias between metal levels. To use a drill file in your import, you click on the Drills button in the Netex-G window. This opens the Drills dialog box which allows you to specify a drill file and the metal layers between which it extends. 24

25 Chapter 2 Gerber Translator Note that this procedure assumes a drill file is in the Gerber format. If you re drill file is not in a Gerber format, you may use the utility, Drill2Gbr, to convert the file to a Gerber format. For more information, please see "Drill2Gbr" on page 26. To select a drill file and define the metal layers between which the vias defined in the drill file extend, do the following. 1 Click on the Drills button in the Netex-G window. The Drills dialog box appears on your display. 2 Click on the browse button to open a browse window to select the desired drill file. Once you select the drill file the name appears in the Gerber File column. 3 Select the Stackup layer you wish to use for the top layer from the drop down list. This is the metal layer where the vias defined in the drill file will terminate. 25

26 Gerber/ODB++ Translator 4 Select the Stackup layer you wish to use for the bottom layer from the drop down list. This is the metal layer where the vias defined in the drill file will originate. The vias extend upward from this layer to the layer specified in the Top Layer drop down. 5 Click on the OK button to close the dialog box and apply the specified drill file. This completes specifying a drill file. Drill2Gbr There are a variety of formats for drill files. If your drill file is not in Gerber format, there is a utility, Drill2Gbr, that allows you to translate your drill file to a Gerber format. This utility allows you to select a drill file, and input options to control how you wish to translate it and converts it to a Gerber format. This converted drill file can then be used in Drills dialog box in the Netex-G window as discussed in the preceding section. To convert a drill file to Gerber format, do the following: 1 In the Drills dialog box, click on the Drill2Gbr button. The Drill2Gbr window appears on your display. The settings for the file you wish to translate should be input here. The settings for how you wish the resulting Gerber file to be formatted should be input here. 26

27 Chapter 2 Gerber Translator 2 Click on a Browse button to open a browse window and select the drill file you wish to convert. The name of the drill file appears in the drill file column. You may translate more than one drill file at a time but all of the files must use the same settings. If the drill tool is not defined in your source drill file, the following warning appears: 3 Click on the OK button in the Warning Message window. The Map Drill Tools to Apertures dialog box appears on your display. This dialog box allows you to define the aperture size for your drill file. Formats vary greatly but there is usually some type of drill table report that you can refer to for the aperture size if you do not already know it. 4 Enter the aperture size in the Diameter text entry box for each drill tool listed. The length units are the units specified in the Drill Format in the Drill2Gbr window. 5 Click on the OK button to close the dialog box and apply the changes. You are returned to the Drill2Gbr window. 27

28 Gerber/ODB++ Translator 6 Enter the Drill Format information for the drill file you are translating. In the Drill Format section of the window, you enter the settings for the drill file you wish to translate. If you have a drill table report available, the settings often may be obtained from it. For details about the fields, please click on the Help button in the Drill2Gbr window. 7 Enter the Gerber Format information which controls how the resulting Gerber drill file is formatted. In the Gerber Format section of the window, you enter the settings you wish to use for the resulting Gerber drill file. If you have selected any Gerber files in the Netex-G window, this information is filled in automatically using information in the input Gerber file. For details about the fields, please click on the Help button in the Drill2Gbr window. 8 Once the settings have been input, click on the Translate button to convert the drill file. Once the translation is complete, the message shown below appears on your display. 9 Click on the OK button to close the message window. 10 Click on the Exit button in the Drill2Gbr window to close it. That completes the translation of the drill file. The translated file is entered in the Drills window. 28

29 Chapter 2 Gerber Translator Windowing NOTE: The window area you select to import is applied to all layers in the stackup. If you wish to select only part of the Gerber metal layers to import, do the following: 1 Click on the Window button in the Netex-G window. Window button The Window dialog box appears. 29

30 Gerber/ODB++ Translator 2 Select the Manual radio button and click on the Launch Gerber Viewer button. The Gerber Importer window appears on your display showing the Gerber metal layers specified in the Netex-G stackup. If you need to view a different layer than the bottom one which is displayed on top by default, you may open the Layer dialog box to control what is displayed in the Gerber Importer. 3 Select File Layer from the menu in the Gerber Importer window. The Layer Table appears on your display. Show checkbox 4 Clear the Show checkbox for any layer you do not wish to display. Those layers will not appear in the display so that you may view the desired layer to select your window. 5 Click on the OK button to close the Layer Table. Next you select the area you wish to translate. 6 If you wish to select a rectangular area, click on the Rectangular window button, then drag your mouse to select the desired area. The selected area is highlighted. 30

31 Chapter 2 Gerber Translator 7 If you wish to select an area which is a polygon, click on the Polygon Window button. Click on each vertex of the desired polygon, double-clicking on the last vertex to close the polygon. 8 In either case, once the desired area is selected, click on the Select button on the tool bar. The Gerber Importer window is closed and control is returned to the Window dialog box you opened in the Netex-G window. 9 Click on the OK button in the Window dialog box to close the dialog box and apply the changes. Only metal which falls within the area you selected is translated when the import is executed. The area is applied to all metal layers in the stackup. This completes the windowing process. Post Conversion Editing Once the conversion is done, you need to complete the setup of your project in order to analyze the circuit. This is also an opportunity to check that your cell size is small enough to prevent open circuits or short circuits. Below is a list of the most common tasks that may need to be done before the analysis is run. If you use a template project, or import to present project, during the import, some of these tasks would become unnecessary if those settings are already correctly defined in the template or present project. Defining material and dielectric layer parameters. Decide on a proper size substrate and cell size. Remove any parts of the circuit that you do not wish to include in the analysis. Change polygons to have the proper fill (Staircase or Conformal Mesh) Align the circuit to grid points. 31

32 Gerber/ODB++ Translator Add ports and reference planes. Specify frequency sweeps. Exporting Sonnet Projects to Gerber Format Files You may export a Sonnet project into Gerber format files. Multiple Gerber files are created when you export your project. The table below details what files are created. 32

33 Chapter 2 Gerber Translator Object in Sonnet Project Metal Level Vias Dielectric Bricks Box Top Box Bottom Project structure File Produced One Gerber file is produced for each metal type on each metal level in your project. If your project only uses one metal type then one Gerber file is produced for each metal level. If you have three metal types on a metal level, then three files are created for that metal level. If the Divide Multi-layer vias option is selected for the export, one Gerber file is created for every two metal levels between which vias extend. For example, if you have vias that extend from metal level 0 to metal level 2, two via files are created; one for the vias that go from level 0 to level 1 and the other for the vias extending from level 1 to level 2. Otherwise a single via file is created. One Gerber file is produced for each dielectric brick type on each metal level in your project. If your project only uses one type of dielectric brick then one Gerber file is produced for each metal level on which dielectric bricks are placed. If you have three types of dielectric bricks on a metal level, then three files are created for the metal level. A special metal layer file, SONNET_TOP, is created for the Sonnet box top. This is useful if you re-import the Gerber files back into Sonnet. A special metal layer file, SONNET_BOTTOM, is created for the Sonnet box top. This is useful if you re-import the Gerber files back into Sonnet. A job file is created with stackup information, dielectric thickness, drill files etc. This job file can be used to re-import your Gerber files into a Sonnet project. To export your Sonnet project and create Gerber formatted files of your circuit, do the following: 1 Open the Sonnet project you wish to export in Sonnet s project editor. 33

34 Gerber/ODB++ Translator 2 Select File Export Gerber from the project editor main menu. The Export Options dialog box appears on your display. These options allow you to control the contents of the output Gerber files, what objects are exported, the Gerber file formats and file names. For details about all the settings in this dialog box, click on the Help button. 34

35 Chapter 2 Gerber Translator 3 Once you have selected the desired options, click on the OK button to close the dialog box and continue the export. A browse window appears which allows you to select the output directory where the translated files are created. When you close the browse window, an output window appears that lists all of the files created by the export. This completes the export of your Sonnet project. 35

36 Gerber/ODB++ Translator 36

37 Chapter 3 Gerber Translator Tutorial Chapter 3 Gerber Translator Tutorial This tutorial teaches you the basics of performing a translation of single or multiple Gerber files into a Sonnet project. There are two program modules, the Gerber Importer window which performs the translation for a single layer translation, and Netex-G which performs the translation for a multi-layer import. For a more detailed discussion of the program modules, please see "Gerber Importer" on page 19 and "Netex-G" on page 21. This tutorial assumes a working knowledge of Sonnet s project editor. 37

38 Gerber/ODB++ Translator This tutorial uses a simple PCB example. The example is found in the examples directory provided with your software and is called Gerber_trans. This example contains a number of files used for the tutorial; the files are listed below. Filename Description M1.gbr M2.gbr Drill_thru.gbr DRILL_THRU.drl drill_table_report.txt Gerber_Tutorial_Full_Board.njb Gerber metal layer file Gerber metal layer file Drill file in Gerber format Drill file in non-gerber format Drill table report Job file used for the Job File translation The first section of this tutorial shows you how to do a single-layer translation. In the second section, a multi-layer translation is performed and includes the conversion of a drill file. The third, and last, section teaches how to translate a job file. In each case, the Gerber files are converted into a Sonnet project. 3-D view of the final Sonnet project that results from the multi-layer import. 38

39 Chapter 3 Gerber Translator Tutorial Obtaining the Translator Example Files You need to copy the example Gerber_trans using the Sonnet Example Browser. You may access the Sonnet Example Browser by selecting Help Browse Examples from the menu of any Sonnet application. For instructions on using the Example Browser, please click on the Help button in the Example Browser window. Save the example to your working directory. Single Layer Translation In the first part of this tutorial you will perform a single layer translation. We will also demonstrate how to select only part of the circuit in the Gerber file for translation into a Sonnet project. The metal layer is pictured below. 1 Invoke the project editor. The project editor window appears on your display. 2 Select File Import Gerber (Single Layer) from the project editor main menu. A Browse window appears on your display. 39

40 Gerber/ODB++ Translator 3 Locate the example file M1.gbr in your working directory and click on the Open button in the browse window. The Import Control dialog box appears on your display. For this example, you want to import the file M1.gbr to a new Sonnet project M1.son. The default option is to import to a new project. The default project name is the basename of the Gerber file with the.son extension of a Sonnet project file. No action needs to be taken since the defaults are correct. 4 Click on the Next button in the Import Control dialog box to continue. The Gerber Importer window appears on your display containing the metal layer you wish to translate. 40

41 Chapter 3 Gerber Translator Tutorial Next you will select the part of the circuit you wish to translate into the Sonnet project. If you wished to import the whole circuit, you would just click on the Import button to continue. 5 Click on he Rectangular Window button in the tool bar of the Gerber Importer window. Clicking on this button allows you to select a rectangular area by dragging your mouse. If you had wanted to select a polygon, you would have clicked on the Polygon Window button. The appearance of the cursor changes. 6 Click and drag your mouse to capture the area you wish to import. Pictured below is the section of the circuit you want to capture. 7 Click on the Import button in the tool bar in the Gerber Importer window. While the file is being imported, a progress window, shown below, appears on your display. 41

42 Gerber/ODB++ Translator Once the import is complete, both the progress window and the Gerber Importer window close and the Layer Mapping dialog box is opened. The Layer Mapping dialog box allows you to map the single Gerber file to a Sonnet metal level, define the type of object, and material. You may optionally create a Technology Layer which is assigned to this Gerber file. The settings are the default settings where the Technology layer name is set to the same name as the Gerber file, and the file is mapped as metal to Sonnet level 0. These default settings are correct for our import so you do not need to take any action. 8 Click on the Next button in the Layer Mapping dialog box. The Layer Mapping dialog box is closed and the Import Options dialog box appears on your display. The Import Options dialog box allows you to control the box and cell size, the positioning of the translated circuit in the Sonnet box, and the properties of translated vias. The default box size is based on the size of the circuit with a margin of 100% on each side. The Auto setting for cell size causes the software to inspect your circuit and attempt to choose an appropriate cell size, which in this 42

43 Chapter 3 Gerber Translator Tutorial case is 2 X 2 mils. The default settings are correct for this tutorial, so no further action is needed. For a detailed explanation of the controls in this dialog box, please click on the Help button. 43

44 Gerber/ODB++ Translator 9 Click on the Next button in the Import Options dialog box. The Import Options dialog box is closed and the Import dialog box appears on your display with Ready to Import displayed in the output window as shown below. Import button 44

45 Chapter 3 Gerber Translator Tutorial 10 Click on the Import button in the Import window to execute the import of the Gerber file into your Sonnet project. The circuit is imported with status updates appearing in the Output window. 11 Click on the Close button in the Import window. The translated project appears in the project editor window as shown below. Translated Circuit Technology Layer 45

46 Gerber/ODB++ Translator Once the circuit is translated into Sonnet, you need to do additional work in the project editor such as setting your box environment, adding components and ports, defining metal types, etc. For example, the material defined by default during the translation was unknown metal. You would need to edit the definition of this metal type. If you are not experienced in using Sonnet, a good place to start is with our Getting Started manual which contains several tutorials. You may access this manual in PDF format through the Manual button on the Sonnet task bar. For more information on components, ports, metal types, and other modeling elements in Sonnet, please refer to the Sonnet User s Guide, which is also available in PDF format. You may also refer to online help, available in most dialog boxes or by selecting Help Sonnet Help in any Sonnet program. Multi-Layer Translation The second part of this tutorial teaches you how to import multiple Gerber layer files and combine them into one Sonnet project. It will also cover how to convert and use a drill file and how to select only part of each layer for translation. 1 Select File Import Gerber (Multi-layer) from the main menu of the project editor. The Import Control dialog box appears on your display. We will use the default name of gerber.son for the new project to which we are importing, so you do not need to change any entries. 46

47 Chapter 3 Gerber Translator Tutorial 2 Click on the Next button in the Import Control dialog box. The Netex-G window appears on your display. You will use this window to set up your metal layer files and drill file for translation. Layer Mapping The first thing you will do in this window is specify the stackup of the Gerber layer files you are importing and the placement of dielectric layers which determines how those layers are mapped to the Sonnet project. It is important that you understand the setup of the Sonnet Box in order to correctly place your metal and dielectric layers. The Sonnet EM analysis is performed inside a six-sided metal box. This box contains any number of dielectric layers which are parallel to the bottom of the box. Metal polygons may be placed on levels between any or all of the dielectric layers, and vias may be used to connect the metal polygons on one level to another. In this example, the file M1.gbr is translated to metal level 0 (the top most metal level) in the Sonnet project. You need to place a dielectric layer above this metal level because the Sonnet box requires that there be a dielectric (most commonly 47

48 Gerber/ODB++ Translator used is air) between the metal level and the box top boundary. In a similar manner, the box bottom can function as the ground plane. If you import M2.gbr with no dielectric layer beneath it, then the metal is placed on the ground plane. In order to preserve what is being imported in M2.gbr, you need to place a dielectric layer below it. Having a dielectric layer below will place M2.gbr on metal level 1 with the dielectric level between it and the box bottom. Below is pictured the input Gerber metal layers (with the drill file placements overlaid) that are used in the stackup for the multi-layer import. Below the two metal layers is shown the resulting Sonnet project with the three dielectric layers added: one between the box top and M1.gbr, one between M1.gbr and M2.gbr and one between M2.gbr and the box bottom. M1.gbr is translated to Sonnet level 0 and M2.gbr is translated to Sonnet level 1. M1.gbr M2.gbr M1.gbr appears on Sonnet Level 0 Dielectric air level between M1.gbr and the box top Dielectric layer between M1.gbr and M2.gbr M2.gbr appears on Sonnet Level 1 Dielectric layer between M2.gbr and the box bottom Box Bottom/Ground Plane The first thing we will add to the stackup is the thick air layer between the M1.gbr metal and the box top. A good guideline for dielectric layer thickness in Sonnet is to set the top dielectric between the box top and highest metal level to four times the thickness of the other dielectric layers. So the air layer above M1.gbr will be set to 0.4 inches and the other two dielectric layers will be set to 0.1 inches. 48

49 Chapter 3 Gerber Translator Tutorial Stackup 1 Layer Type Drop List 3 In entry number 1 in the Stackup, select Dielectric from the Layer Type drop list. Stackup 2 button This places a dielectric layer between M1.gbr and the box top. If you wish you may enter a thickness for the dielectric layer you just selected. If you do not enter a thickness during the translation, you will need to enter a dielectric thickness in Sonnet. For this tutorial, we will enter a thickness for all the dielectric layers. 4 Change the Layer Name to Air_above for entry number 1. When you selected Dielectric as the Layer Type, the default name of D1 appeared. Note that the underscore is required in the name since spaces are not allowed in layer names. 49

50 Gerber/ODB++ Translator 5 Click on the Details button just to the right of the drop list. The Layer Details dialog box appears on your display. Thickness text entry box 6 Enter a value of 0.4 in the Thickness text entry box. This sets the dielectric layer between the top metal layer and the box top to 0.4 inches. The length units are read in from the Gerber file once you specify one in the stackup. The units are displayed at the bottom of the Netex-G window. For this example, the Gerber files use inches as the length unit; however, since a Gerber file has not yet been specified in the stackup the units are not yet displayed. 7 Click on the OK button and close the dialog box. 8 Click on the 2 button to select a Gerber file to be used for entry 2 in the stackup. A browse window appears on your display. 50

51 Chapter 3 Gerber Translator Tutorial 9 Select the file M1.gbr from your working directory. When the browse window is closed, the entry M1.gbr appears in the Gerber File column under the Stackup 2 entry as pictured below. Note that once this file is specified in the stack up, the length units are read from the Gerber file and displayed at the bottom of the Netex-G window. Stackup 2 Entry Length Units Displayed 10 In entry number 3 in the Stackup, select Dielectric from the Layer type drop list. This places a dielectric layer between the two metal levels you are importing. 11 Click on the Details button just to the right of the drop list. The Layer Details dialog box appears on your display. 12 Enter 0.1 in the Thickness text entry box. This sets the dielectric layer between the two metal levels to 0.1 inches. Note that each dielectric layer in a project may be set to a different thickness. 13 Click on OK to close the Layer Details dialog box. 14 Click on the 4 button to select a Gerber file to be used for entry 4 in the Stackup. A browse window appears on your display. 51

52 Gerber/ODB++ Translator 15 Select the file M2.gbr from your working directory. When the browse window is closed, the entry M2.gbr appears in the Gerber File column under the Stackup 4 entry as pictured below. Stackup 4 Entry 16 In entry number 5 in the Stackup, select Dielectric from the Layer type drop list. This places a dielectric layer beneath the second metal layer. The Sonnet box bottom will be under this dielectric layer in the Sonnet project. By default, the box bottom is treated as the ground plane. 17 Click on the Details button just to the right of the drop list. The Layer Details dialog box appears on your display. 18 Enter 0.1 in the Thickness text entry box. This sets the dielectric layer between the box bottom and the lowest metal level to 0.1 inches. 52

53 Chapter 3 Gerber Translator Tutorial 19 Click on OK to close the Layer Details dialog box. The Netex-G window should appear as below. Drill File In most PCB designs, there are vias between the metal layers. The location of the center point of each via is contained in a drill file. The aperture size is usually provided in a drill text file, such as a drill table report. You will use a drill file to create the vias in the Sonnet project. Drill files can vary greatly across the industry which is why in many cases, you may need to translate your drill file into a Gerber format; this extra step is demonstrated in the tutorial as well. We provide one example of a drill file and drill table report and show you how to take the information in those files and translate it. Your source files when translating your files may differ considerably. 53

54 Gerber/ODB++ Translator 20 Click on the Drills button in the Netex-G window. The Drills dialog box appears on your display. Since your drill file is not yet in Gerber format, you will need to use the Drill2Gbr utility to convert the supplied drill file to a Gerber format. 21 Click on the Drill2Gbr button in the Drills dialog box. The Drill2Gbr window appears on your display. This dialog box allows you to convert the supplied drill file, DRILL_THRU.drl, to a Gerber format. You also need to reference the drill table report also supplied with your example in order to setup the conversion of the drill file properly. 54

55 Chapter 3 Gerber Translator Tutorial 22 Click on the Browse button in the first entry under Drill Files in the Drill2Gbr dialog box. 23 In the browse window which appears select DRILL_THRU.drl from your working directory. You may need to select All Files from the Files of Type: drop list in order to display the file. When you select the file a warning message appears. Drill files specify a drill point location and the drill aperture size determines the size of the via. This warning message indicates that the aperture sizes have not been defined for the drills cited in the source file. Therefore, you will specify them in the next step. 55

56 Gerber/ODB++ Translator 24 Click OK to open the Map Drill Tools to Apertures dialog box. You will need to enter a Diameter for both Drill Tool 1 and 2. This information can be found in the Drill Table report. A drill table report has been supplied as part of your example. Open this report in a text editor to find the necessary diameters. The Drill Table report is shown below with the drill sizes highlighted: Tuesday September 30, 2008; 15:42:27 DRILL TABLE Drill Position Drill Size Upper Bound Lower Bound Plated Drill Type Symbol yes MECHANICAL yes MECHANICAL --- DRILL FORMAT Drill machine coordinate mode is ABSOLUTE Drill machine supports INCH units Scale is Data format is 3.4 Drill machine modal coordinate is OFF Leading zeros are PRESENT Trailing zeros are NOT PRESENT Drill machine origin (x, y) at (0.0, 0.0) Drill machine command block end char is '' Drill machine stop code is 'M30' 56

57 Chapter 3 Gerber Translator Tutorial 25 Enter the value 0.02 in the Diameter entry box for Drill Tool 1 and the value 0.04 in the Diameter entry box for Drill Tool Click on the OK button to close the dialog box and apply the changes. The Drill2Gbr dialog box appears on your display with the specified drill file shown in the first entry. You now need to fill in the Drill Format properties in order to complete the translation of the drill file. The Drill2Gbr program looks at the Gerber files previously specified in the Netex-G window and automatically fills in the Gerber Format fields. You should set the Drill Format fields to match the Gerber Formats. Gerber Formats Drill Formats 57

58 Gerber/ODB++ Translator 27 Under Drill Format, set Format to 3.4 and Units to IN and Zero Inclusion to Leading. The Coordinates are already set to Absolute, so you need to take no action. Once you have entered these values the dialog box should appear as shown below: Drill File Name 28 Click on the Translate button at the bottom of the Drill2Gbr window. A translation completed message appears when the translation is done. Note that the translated drill file is called < basename>.gbr where < basename> is the basename of the input drill file which in this case means that your translated drill file is DRILL_THRU.GBR. This file is created in the same directory as the source drill file. 29 Click on the OK button to close the message window, then click on the Exit button to exit the Drill2Gbr window. The Drills dialog box appears on your display. 58

59 Chapter 3 Gerber Translator Tutorial 30 Click on the top Browse button to select the translated drill file DRILL_THRU.GBR. This name appears in the first entry of the Gerber File column. Next you must specify the metal layers between which the drill holes should go. If you look at the Stackup in the Netex-G window, the top metal layer is on Layer 2 and the bottom metal layer is on Layer 4, so the drill file should extend from Layer 2 down to Layer Select 2 from the Top Layer drop list and 4 from the Bottom Layer drop list in the first entry to the right of the drill file name. This completes the entry of the drill file you wish to use in the translation. 32 Click on the OK button to close the Drills window and return to the Netex-G window. It is not unusual to translate only part of the metal layers. The last step in setting up the translation is to select which part of the metal layers you wish to translate into the Sonnet project. Windowing 33 Click on the Window button on the right side of the Netex-G window. The Window dialog box appears. 59

60 Gerber/ODB++ Translator 34 Click on the Manual radio button under Window Coordinates. The Launch Gerber Viewer button is enabled. 35 Click on the Launch Gerber Viewer button. The Gerber Importer window appears displaying all the metal levels and the drill file. In order to select the correct area in the circuit, you need to see the top metal level. 60

61 Chapter 3 Gerber Translator Tutorial 36 Select File Layer from the main menu in the Gerber Importer window. The Layer Table window appears. You need to stop displaying M2.gbr in order to see M1.gbr. Show Checkbox 61

62 Gerber/ODB++ Translator 37 Click on the Show checkbox in the Layer 2 entry to deselect M2.gbr. 38 Click on the OK button in the Layer Table to close the window and apply the changes. The Gerber Importer window is updated and now shows the top metal layer. 62

63 Chapter 3 Gerber Translator Tutorial 39 Click on the Window button in the tool bar and click and drag the mouse to select the portion of the circuit you wish to translate. The section you should select is shown below. 40 Once you have selected the desired portion, click on the Select button in the tool bar. This closes the Gerber Importer window and returns control to the Windows dialog box in Netex-G. 41 Click on the OK button in the Window dialog box. The Windows dialog box is closed. This completes the setup for your multi-layer import and you are ready to perform the actual translation. 42 Click on the Import button in the Netex-G window. When you click on the Import button, a browse window appears so that you can save a job (.njb) file for the import. 63

64 Gerber/ODB++ Translator TIP The job file stores all of the settings you just input in the Netex-G window and may be used to do subsequent imports so that you do not have to go through the setup process each time you make a change in your Gerber source files. The third part of the tutorial, "Job File Translation" on page 68, shows you how to do a Gerber import using a job file. 43 Enter the name My_Gerber_Tutorial.njb and save the file in your working directory. When the browse window is closed, the import starts. A progress window appears on your display, as shown below, that allows you to track the progress of the import. When the import is complete, the progress window closes and the Import Options dialog box appears on your display. The Import Options dialog box allows you to control the box and cell size, the positioning of the translated circuit in the Sonnet box, and the properties of translated vias. The default box size is based on the size of the circuit with a margin of 100% on each side. For the purpose of demonstration, we will use only a 10% margin on each side to create a smaller box size. 64

65 Chapter 3 Gerber Translator Tutorial 44 Enter a value of 10 in each of the Side Margin text entry boxes in the Box Size section of the dialog box. The dialog box should appear similar to that pictured below. The rest of the settings are correct and require no further action. For a detailed explanation of any controls in the dialog box, please click on the Help button. Side Margin text entry boxes 45 Click on the Next button in the Import Options dialog box. The Import Options dialog box is closed and the Import window appears on your display with the message Ready to Import displayed. 65

66 Gerber/ODB++ Translator 46 Click on the Import button to import the Gerber files into your Sonnet project file. The output window is updated with status messages as the import progresses. When the import is complete, the message Press Close button to finish appears at the top of the window as shown below. 47 Click on the Close button in the Import window. The translated circuit now appears in Sonnet s project editor with a view of Sonnet metal level 0. This is the level to which the source file M1.gbr was translated. Notice that the specified dielectric layers are displayed in the stackup manager, as well as the Technology Layers created during the import. The Metal Technology 66

67 Chapter 3 Gerber Translator Tutorial layers are named after the basename of their source file. The Via Technology Layer was created using the settings in the drill file. Note that the circuit is close to the box walls since we used margins of only 10%. V1 Via Technology Layer M2 Metal Technology Layer Stackup manager Viewing your circuit in 3D allows you to see if your setup translated correctly. 67

68 Gerber/ODB++ Translator 48 Select View 3D from the project editor main menu. A new window is opened in the project editor with a 3D view of your imported project. Since you entered thickness values for the dielectric layer during the translation, the metal layers are separated. If you had not entered those thicknesses, you would need to enter them in Sonnet (Circuit Dielectric Layers). M1 metal M2 metal Vias created using drill file Once the circuit is translated into Sonnet, you need to do additional work in the project editor such as setting your box environment, adding components and ports, defining metal types, dielectric stackup, etc. If you are not experienced in using Sonnet, a good place to start is with our Getting Started manual which contains several tutorials. You may access this manual in PDF format through the Manual button on the Sonnet task bar. For more information on components, ports, metal types, and other modeling elements in Sonnet, please refer to the Sonnet User s Guide, also available in PDF format. You may also refer to online help, available in most dialog boxes or by selecting Help Sonnet Help in any Sonnet program. This completes the second part of the Gerber translator tutorial. The third part of the tutorial shows you how to perform a translation using a job file (.njb). Job File Translation Gerber Job Files allows you to retain all of the settings you entered in Netex-G during a multi-layer import including the stackup order, specified input files, drill files, windowing information, etc. As you perform design iterations and produce updates for your Gerber files, it would be inefficient to have to perform the whole 68

69 Chapter 3 Gerber Translator Tutorial setup process in Netex-G when you need to re-import into a Sonnet project. Therefore, as you saw in the last section of the tutorial, once you have completed the setup in Netex-G, your input settings are saved to a job file. This section of the tutorial teaches you how to perform a Gerber file import using a job file. First, you use the job file you created in the previous section of the tutorial to perform an input. You perform a second job file import, using a supplied job file, to demonstrate what occurs when you change the location of a job file on your system or network. 1 Select File Import Gerber (Job File) from the main menu of the project editor. A browse window appears on your display to allow you to select a job file for the import. 2 Go to your working directory and select the file My_Gerber_Tutorial.njb that you created in the last section of the tutorial. Once the file is selected, the Import Control dialog box appears. You will use the default project name provided, so there is no need to change any settings in this dialog box. 69

70 Gerber/ODB++ Translator 3 Click on the Next button in the Import Control dialog box. The Netex-G window appears with its settings populated by the contents of the job file and should appear similar to the picture below. When doing a job import, if you wish, you may make changes in the setup using the Nextex-G window. If you do make changes to the settings, than the job file you are using is updated. There is no need to make any changes for the tutorial. Import button 70

71 Chapter 3 Gerber Translator Tutorial 4 Click on the Import button in the Netex-G window to continue. When the import is launched, the Netex-G progress windows appears on your display. Once Netex-G is done converting your files, the progress window closes and the Import Options dialog box appears on your display. 71

72 Gerber/ODB++ Translator 5 Enter 100 in each of the Side Margin text entry boxes. This increases the box size and provides more distance between the circuit and the box wall. The rest of the settings are correct and require no further action. 72

73 Chapter 3 Gerber Translator Tutorial 6 Click on the Next button in the Import Options dialog box. The Import window appears on your display with the message Ready to Import. Import button 7 Click on the Import button to create your Sonnet project. Status messages will be displayed in the Status Control window showing the progress of the import. When the import is complete, the message Press Close button to finish. appears at the top of the Import window. 73

74 Gerber/ODB++ Translator 8 Click on the Close button in the Import window. The Import window is closed and your imported circuit is displayed in the project editor window. 74

75 Chapter 3 Gerber Translator Tutorial 9 Select View View 3D from the project editor main menu. The 3D view of your circuit appears allowing you to see the imported metal layers and the vias. The scale on the Z dimension is increased so that the separate metal levels may be viewed with clarity which may differ from what is shown on your display. 10 Close the 3D viewer window before continuing. You may do so by clicking on the X button in the upper right hand corner of the 3D window. Changing Directories of Job Files If you have moved your source files or are using a job file copied from another location, then the working directories used by the job file are incorrect. The program can correct this for you, but there are some additional steps to import a job file with a job file that has been relocated. The source files and job file should be placed in the same directory. The next section of the tutorial demonstrates how to do this. 75

76 Gerber/ODB++ Translator 1 Select File Import Gerber (Job File) from the project editor main menu. A browse window appears on your display to allow you to select a job file for the import. 2 Go to your working directory and select the file Gerber_Tutorial_Full_Board.njb that was supplied with your example files. Once the file is selected, the Import Control dialog box appears. You will use the default project name provided, so there is no need to change any settings in this dialog box. 3 Click on the Next button in the Import Control dialog box. The Import Control dialog box is closed and Netex-G is invoked. When Netex-G is invoked, the first thing that is done is to open the job file. When you are importing a job file that was moved from another location, all of the working directories need to be updated. So when Netex-G opens the job file, a series of warnings about the working directories appear. When you click on the OK button 76

77 Chapter 3 Gerber Translator Tutorial in the message windows, the working directory in the job file is set to the directory in which the job file now resides. A series of message boxes explaining the change appear as shown below. The directory listed in the job file. The present working directory, the program defaults to looking for the files there. 77

78 Gerber/ODB++ Translator 4 Click on the OK button in each Warning Message box to change the directories. Once all the warning messages have been closed, the Netex-G window appears on your display. There is no need to make any changes in the Netex-G window, all of the settings from the job file are entered. 78

79 Chapter 3 Gerber Translator Tutorial 5 Click on the Import button in the Status Control window. When the import is launched, the Netex-G progress windows appears on your display Once Netex-G is done converting your files, the progress window closes and the Import Options dialog box appears on your display. The settings in the dialog box are from the previous section of the tutorial since 79

80 Gerber/ODB++ Translator the Remember settings checkbox is selected so you need take no further action. 80

81 Chapter 3 Gerber Translator Tutorial 6 Click on the Next button in the Import Options dialog box. The Import window appears on your display with the message Ready to Import. Import button 7 Click on the Import button to create your Sonnet project. Status messages will be displayed in the Status Control window showing the progress of the import. When the import is complete, the message Press Close button to finish. appears at the top of the Import window. 81

82 Gerber/ODB++ Translator 8 Click on the Close button in the Import window. The Import window is closed and the imported circuit is displayed in the project editor. Note that this job file contained no windowing information, so the complete metal layers were imported. This completes the Gerber Translator tutorial. 82

83 Chapter 4 ODB++ Translator Chapter 4 ODB++ Translator The ODB++ data exchange format is used to transfer a product model of a PCB layout to a manufacturer. A single archive file or directory contains all of the information necessary to specify a PCB layer. The ODB++ translator allows you to convert a ODB++ archive file or directory to a Sonnet project compatible file. Once you have converted your ODB++ archive or directory to a Sonnet project, you then need to adjust it using the project editor before you can analyze the circuit with em. This chapter discusses using Sonnet s project editor and assumes that the user is very familiar with the project editor. NOTE: The ODB++ translator is only available if you have purchased a Gerber Multi-file translator license from Sonnet. Please see your system administrator if you are unsure of the availability of this program. The ODB++ Translator is only available on Windows Platforms. Converting your files to Sonnet The ODB++ translator inputs an ODB++ archive or compressed file (.tgz,.tar,.gz,.zip or.tar) or a directory of files from a circuit layout program and converts the files in the archive to a Sonnet project. The translator is accessed through the project editor. The ODB++ translator proceeds in a manner very similar to a Gerber multi-file import, except that the ODB++ archive file or directory is 83

84 Gerber/ODB++ Translator imported into the Netex-G window, and the files in the archive or directory populate the Netex-G window. Therefore, we recommend reading the Chapter 2 "Gerber Translator" on page 13 first. For more information on the dialog boxes used during the import, please refer to Help by searching on ODB++ Translator in the index or by clicking on the Help button of any of the dialog boxes. 84

85 Chapter 4 ODB++ Translator ODB++ Import The ODB++ import allows you to import a product model archive or directory which contains the layer files to be imported as well as files to control the stackup. The archive is imported and opened, and the files are used to set the inputs of the Netex-G window very similar to performing a Job import for Gerber files. Select File Import ODB++ from project editor main menu. Import Control dialog box Specify destination project, optional template file, and set technology layers checkbox. Netex-G window Open the ODB++ import window. ODB++ Import window Import the ODB++ archivefile which populates the Nextex-G window Import Options dialog box Controls project length units, sets conversion standards and sets via properties. Import window Allows you to execute the Import and display conversion status. Sonnet Project Post Conversion Editing 85

86 Gerber/ODB++ Translator ODB++ Import Window The ODB++ Import window is opened during an ODB++ import, when you select File Import ODB++ from the main menu in the Netex-G window. Input Open button Preview button Imported Layers Import button This window allows you to identify the archive file or directory you wish to import, preview the circuit and then import the archive or directory into Netex-G. To import an ODB++ file, do the following: 1 Select File Import ODB++ from the main menu of the project editor. The Import Control dialog box appears as detailed in the descriptions of the Gerber imports. Once you have made your selections and clicked on the Next button, the Netex-G window appears on your display, with the ODB++ Import 86

87 Chapter 4 ODB++ Translator window open, as shown below. Note that all of the inputs in the Netex-G window are blank. For more information about the Netex-G window, see Netex-G, page 21. File radio button Directory radio button 2 In the ODB++ Import window, select the radio button for the type of input you wish to import. If you are importing an archive file (.tgz,.tar,.gz,.zip or.tar), you select the File radio button. If you wish to import an ODB++ directory of files, select the Directory radio button. 3 Enter the name of the desired archive file or directory in the Input text entry box. You may directly edit the contents of the Input text entry box, or use a browse window which allows you to select the archive file or directory on your computer. 87

88 Gerber/ODB++ Translator 4 Click on the Open button to open the archive file or directory. If you have not entered an archive file or directory in the Input text entry box, then a browse window is opened to allow you to select the archive file or directory on your computer. Once you have selected the input, the archive file or directory in opened. Once the processing is complete, a message saying Open Status: Successful appears on your display, similar to that shown below. The window is also updated to display the layer files that were opened. Layer Files 5 If you wish to preview your circuit before importing, click on the Preview button. The Preview button is enabled once the input has been identified. This is an optional step. 88

89 Chapter 4 ODB++ Translator 6 Click on the Import button in the ODB++ window to import the archive or directory. A progress window appears and is updated while the conversion is done. Once the conversion to Gerber is complete, a message window appears, as shown below, indicating that the conversion has completed. 89

90 Gerber/ODB++ Translator 7 Click on the Ok button in the message window. The message window is closed and the Netex-G window is updated with the contents of the archive or directory that was imported; an example is shown below. The names of layer files appear in their correct position in the startup. If the archive or directory contained any drill files, these are also input. The rest of the translation process is the same as when performing a Job File Gerber input. There is an example of a Gerber Job File input in Chapter 3 "Gerber Translator Tutorial" on page

91 Appendix I Via Simplification Appendix I Via Simplification Introduction Several manufacturing processes used to produce RF circuits utilize via arrays or bar via groups to provide the trace metal layer to layer connections. Both of these types of vias present an analysis challenge which drives the Sonnet model memory and analysis time requirements beyond what is practical to analyze. Via simplification provides an approach to via arrays and bar vias that reduce the time and memory requirements without sacrificing accuracy. These two processes are discussed in this appendix. Via Array Simplification For via arrays, the small size of the individual vias and the large number in the array usually drive Sonnet model memory and analysis time requirements beyond what is practical to analyze. This often requires that you simplify the via geometry detail before performing your EM simulation. In the past, via array simplification would need to be done manually by deleting vias and replacing with a single, larger via polygon. 91

92 Gerber/ODB++ Translator The Simplify Via Array feature automatically performs this simplification during the translation process. It can be invoked inside the Keysight ADS Interface, the Cadence Virtuoso Interface, NI AWR Microwave Office Interface - 32 Bit and NI AWR Microwave Office Interface - 64 Bit. It may also be invoked in Sonnet s project editor when performing an import using the Gerber/ODB++ Translator, GDSII Translator or DXF Translator. Via Array Criteria There are six criteria, all of which must be met, before a group of vias in the original geometry is considered an array and therefore simplified by the software. Number of Vias: There must be a minimum number of vias in order for them to be considered an array. Via Size: The vias must be the same size or nearly the same size. Via Spacing: The vias must be within a certain distance of one another. Layer Pass Through: The vias must pass through the same layer(s). Metal Polygons Pads: The vias must be contained within the same metal polygon at either the top or the bottom of the vias. Material: The vias must be set to the same material, whose conductivity is the same. Additional Simplify Via Array Options This text entry box should only be used at the direction of a Sonnet representative. Simplify Via Array Options There are six control options for the simplify via array feature which are discussed in detail in the following sections. We will use a simple example circuit to illustrate how the options affect the via simplification. 92

93 Appendix I Via Simplification TIP The default values were determined based on extensive testing, and in the majority of cases will provide reasonable via simplification behavior. However, Sonnet handles a wide range of layouts and processes, so these controls were provided so that a user can customize the translation if it proves necessary. The example structure consists of three metal layers and two interconnecting via arrays, as shown below. Since the vias pass through different dielectric layers and use different metal types, the 1 X 2 array and the 5 X 5 array would never be grouped together. Either reason would be sufficient on its own to prevent these two arrays being grouped together. The 1 X 2 via array extends from metal level 0 to metal level 1 through the upper dielectric layer. The 5 X 5 via array extends from metal level 1 to metal level 2 through the lower dielectric layer. 1 X 2 via array. Each via is 1 μm square and the assigned metal type is Via1. 3D View of circuit 5 X 5 via array. Each via is 4 μm square and the assigned metal type is Via2. 2D View of Metal Level 1 93

94 Gerber/ODB++ Translator Minimum Vias in Array This control defines the minimum number of vias which can be considered part of the same array. The default value for this setting is 5, so that only arrays with 5 or more vias will be considered for simplification. Therefore, in our example the 1 x 2 via array would not be simplified, but the 5 X 5 would be analyzed to see if this array meets the rest of the simplification criteria. You may enter any integer value to set the minimum number required. 1 X 2 Via array Will not be simplified 5 X 5 Via Array Will be simplified Max Distance to Size Ratio This control defines the maximum spacing between vias which can be considered part of the same array. While the distance between vias is measured from the center lines of the individual vias, the control is a ratio of distance to via size. This distance cannot exceed the value of this ratio multiplied by the via size. The default setting is 4.0 and the larger the value, the more widespread the vias can be and still be grouped in the same array. Since individual via cross-sections can be of any shape, the square root of the via area is used as the via size. 94

95 Appendix I Via Simplification For our example the size of the vias is 2.0 μm and the center to center spacing is 4.0 μm, as pictured below. This results in a Distance to Size ratio of 4.0/2.0 = 2.0 so that this array meets the via spacing criteria. The center to center spacing is 4 μm. The size of an individual via is 2μm. Maximum Size to Size Ratio This control defines the maximum allowable difference in via size to be considered part of the same array. The default value of this ratio is 1.5 and the larger the value, the greater the difference of via size is allowed within an array. Since individual via cross-sections can be of any shape, the square root of the via area is used as the via size. For this example, the via cross-section is a 2.0 X 2.0 μm square. The area is 4 μm 2 and taking the square root, yields a via size value of 2 μm. Since all of the vias are the same size in this array (2.0 μm) the Size to Size ratio is 1.0, so that this array meets the via size criteria. TIP If you wish to limit your arrays to vias of the same size, set this control to 1.0. Max Expansion Coefficient This control helps define the size of the resulting simplified via by allowing it to be larger than the original via array perimeter (also referred to as the bounding box). The default value is 7.0, which allows the simplified via to expand outward by a factor of 7 times the largest via size in the array. The advantage in expanding 95

96 Gerber/ODB++ Translator the simplified via is that it can often be sized to match the polygons to which the via attaches. Having the via polygon edge and pad polygon edge in alignment can significantly reduce the subsection density in the region and thereby reduce the memory requirement of the model. An example is shown below. The algorithm looks outward from an imaginary rectangle (bounding box) drawn around the perimeter of the array (green rectangle). The distance checked out from the perimeter is the Max Expansion Distance (shown in red arrows). It is equal to the Max Expansion Coefficient times the largest sized existing via in the array. If a vertex from a pad polygon is encountered within this window (red rectangle), the expansion stops and this sets the simplified polygon edge. If no vertices are found in a particular direction, the edge of the simplified via rolls back to the existing via array perimeter. Please note that all metal levels are examined when looking for vertices within the maximum expansion distance. The Max Expansion Distance is denoted by the red dashed box and is 7.0 times (default value) the largest via size (2.0 μm) = 14.0 μm. The blue stars are vertices within the max expansion distance on this metal level. The yellow star indicates a vertex found on another metal level. The via array perimeter is indicated by the dashed green box. If no vertices are found in that direction, then the perimeter defines the edge of the simplified via in that direction. The dashed blue box above shows the final size of the simplified via. On the top, bottom and right hand side the via extends to the vertices and on the left side it conforms to the array bounding box (dashed green box) since no vertices were found within the maximum expansion distance in that direction. 96

97 Appendix I Via Simplification TIP The default setting for Max Expansion Coefficient is 7.0. If you wish the simplified via to be the bounding box around the array, set the Max Expansion Coefficient to 0, which allows no expansion. Merge Planar Polygons During Simplification In order to be considered an array, a group of vias must connect to a single polygon on the top and bottom of the group. This control allows the user to merge the polygon pads or traces prior to simplifying the vias. This results in larger arrays being recognized leading to the least number of simplified vias, thereby producing the most efficient model. This option is enabled by default. The option is illustrated below using the example circuit. The trace is divided into two parts (black outlines show the two polygons). If the Merge Planar Polygon option is not selected, then the array is treated as two via arrays (indicated by the dashed red boxes) and two simplified vias are created. If the option is on, however, the two parts of the trace are merged into one polygon and the whole array is simplified into one via. NOTE: The polygons are only temporarily merged for via simplification and will not be merged in the resulting Sonnet project. 97

98 Gerber/ODB++ Translator Number of New Via Metals Created Via metal types using the Array loss model are created to model your simplified vias in Sonnet. This setting controls how many via metal types are created in your translated project in order to model your simplified array. The fill factor is used to determine how many metal types are created. For more information on the fill factor and the Array loss model, please see Array Loss Model in the Sonnet User s Guide. There are three choices: Minimum: Creates the least number of via metal types but may be less accurate as a wider range of fill factors will be grouped together. Automatic: Creates the via metal types based on an algorithm that balances the trade off between accuracy and the number of via metal types produced. This is the default setting. Maximum: Creates the highest number of via metal types providing the most accurate answer since a via metal type is created for each unique fill factor. Simplified Via Array Loss When an array is converted to a simplified via, a via metal type using the Array Loss model is created, if it does not yet exist. For example, you are translating an array which uses ViaMetal1 for an array. During the translation a via metal type ViaMetal1 is created that uses the Array Loss model. During translation, one source metal may be translated into two metal types if there is a significant difference in individual via size in different arrays using the same metal. For more information about via metal types and defining their loss, please see Array Loss Model, in the Sonnet User s Guide. The simplified via is modeled using the same meshing fill as the vias in the original via array. For a detailed discussion of meshing fill for via polygons, please see Meshing Fill for Vias in the Sonnet User s Guide. 98

99 Appendix I Via Simplification Bar Via Group Simplification Bar vias are vias whose length is significantly longer than their width. They are typically used in stacked multi-level conductors where vias carry horizontal currents. An example is shown below, with one of the bar vias highlighted in black. For vias whose aspect ratio is smaller, such as 1:1, the Sonnet model assumes that there is little to no horizontal current in the via. The assumption is that current flows in the vertical or z-direction. For bar vias, whose aspect ratio is larger, the current flow in the horizontal direction is more significant. Bar via groups placed on metal traces also drive a very fine resolution in the meshing that can require an inordinate amount of processing resources. The Identify Bar Vias feature identifies bar vias in the translated circuit based on length to width ratio entered by the user. These vias are assigned the Bar via meshing fill, then during the analysis multiple adjacent bar vias are identified as a bar via group and merged into one wider via during the subsectioning by the analysis engine, em. Since via arrays are simplified during translation, their appearance in the project editor is that of the simplified via polygon into which the via array was converted. However, in the case of bar vias, the actual via polygon input by the user is displayed in the project editor, because no simplification has yet been done. If you wish to see the actual metal for the simplified bar vias that are used in the simulation, you should view the subsections for the circuit. For a detailed 99