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What is LASI

LASI (LAyout System for Individuals) is a relatively simple "general purpose" layout and design system originally intended for integrated circuits. It is versatile enough that it can be used for ICs, MEMS and other nanotechnolgies, discrete devices, schematics, PC boards and project documentation drawings. LASI is intended for both educational and professional use.

A very simple version of LASI was written for MS-DOS in the mid-80's. When Windows came out, LASI was rewritten as version 6 for Windows. The current version 7 is more elegant, functional and runs on all Windows versions.

For students LASI teaches a better understanding of what you are really doing. To use LASI, you need to know something about your technology, the physics involved and have some circuit intuition, not just know how to run software. It is for people who still consider IC design something of an art.

The original intention of LASI was to aid commercial design systems. It still has that purpose since layout work can be done on any Windows PC or Laptop, Linux systems using Wine, and then be transferred using common formats such as GDS.

LASI also runs portably. You can install the system on a flash drive or other removable drive and work on drawings also stored on that same drive. Portable operation lets you do work on any convenient PC without leaving any files on that PC. This is handy for presentations and for student projects.

Drawings are built from hierarchical cells stored as individual TLC (Transportable Layout Cell) files. TLC files can be easily traded between different drawings. TLC files are in a basic XML format.

LASI consists of a main drawing editor program and several "utility" programs. These utilities include GDS, CIF and DXF format converters, a user programmable bitmap based DRC, a basic matrix router, and a Spice netlist compiler that extracts Spice circuit files from both schematic and layout. The utilities can run independently or directly out of the editor.

LASI compiles Spice netlist files but does not do simulations. There are good Spice simulators available already. Spice simulations can be quite customized and are better not integrated into LASI. However most simulators can run directly out of the main editor or the Spice compile utility.

For anyone who is not familiar with LASI or its utilities there is a large built-in Help file system.

Although it is well developed software by now, LASI is still an ongoing project. There is always something that you can add, improve or fix. Watch this site for the latest version. Updates are approximately every couple of months, longer if few changes, sooner if necessary.

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What's New

7.0.75

• The GDS conversion utilities Gds2Tlc and Tlc2Gds now write text files that translate the binary GDS records to plain text. These files should be educational and very useful as diagnostics by showing what is really written in a GDS file.

• The Spice compiler LasiCkt has been greatly revised to make it much easier to compile Spice circuit files from layout or schematic. It will run as previous versions, or as a two pass compiler. On the first pass, it writes script files that add Connector Text on real or virtual nodes. On a second pass, it reads the script, temporarily adds connectors to the cells and recompiles. Adding connectors lets you find certain layout errors that might be missed.

• The Spice compiler LasiCkt has also had some setup changes that eliminate some rarely used options. It also has some improved checks for cell layout errors that can cause incorrect or unworkable Spice circuit files.

• Most of the LASI Addon tutorials have been updated with revised LasiCkt sample compiles and connector scripts.

7.0.74

• The progress bar has been removed from the LasiCkt Spice compile display. Running under Windows 7 it was slow and erratic. The bar was not very useful because LasiCkt is an event driven program where it is difficult to accurately measure progress.

• The LASI Setup date should now always be correct. In the 7.0.73 release the date might have been taken from a previous file that had not been deleted.

• The rarely used utility programs Lasipgl7.exe and Calma2tlc7.exe now both install in the \Lasi7 folder. Use the Run command to start them.

• Design Rule Check DRC files for LasiDrc now contain check code sequences for metal overlaps. These checks are currently turned off as comments.

• On Windows 7 when a tooltip pops up the LASI editor sometimes redraws if you are NOT using Aero themes. Windows 7 sends the LASI editor a "window  paint" message. On large drawings this can be a problem. Checking "Hide Tooltips" under Cnfg prevents this from happening. Utility program tooltips can also cause a redraw. Hide Tooltips is now also passed to utility programs.

7.0.73

• The Spice compiler utility LasiCkt can now automatically add connector text to a layout. By adding additional connector text LasiCkt can better detect certain layout errors.

• The cursor information in the lower left of the editor screen and the editor distance measuring tool now show the cursor vector angle.

• When calculating parasitic capacitances LasiCkt now reads out the capacitance node names.

• The Arc command can now generate certain basic spiral types for special integrated devices.

7.0.72

• Compiling schematics with LasiCkt with Auto Depth set did not work correctly in the previous release. The bug should be fixed.

• An old bug in LasiDrc that caused a white vertical stripe when viewing a PCX bitmap has been fixed.

• An asterisk "*" can now be used as a comment character in Command Line Script and in DRC files.

• As usual, many small changes and updates in the Help files.

7.0.71

• You can now save a cell directly in Command Line Script. The Save command has a check box option. This is useful if you want to create or edit individual cells or parts of a cell with a text editor and then add them to other cells.

• Some of the keyboard permanent key assignments in the drawing editor have been changed.

• If a secondary line or rectangle cursor is showing and a key that executes a different command is pressed, the cursor is erased (old bug).

• When run on Windows 7 the toolbar buttons now show either text or icons, not a combination of both when text only is chosen.

• The cell library Edulib has been modified so that when running an LVS with LasiCkt, the layout cells RINGOSC31, DELAYOSC and 4COUNTER now compare correctly with their corresponding schematics.

• Many small changes and updates in the Help files.

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