LEF View screenshot
Screenshot (click to enlarge)


LEF View is a Firefox extension that allows you to view LEF files. It is implemented using XUL, SVG, and Javascript. Because it requires SVG it will only work with Firefox 1.5 or greater, since SVG was not implemented in Firefox 1.0.x.

One word of warning is called for I think. You should be careful about what you try to read in. I have successfully read in a LEF for a reasonably sized standard cell library but it took a while and Firefox asked if I wanted to stop the script several times (how do I get rid of this by the way?). I also read in a fairly big memory macro which worked fine, although the zooming started to feel slightly sluggish.

What is LEF?

LEF (short for Library Exchange Format) is used by CAD tools in the EDA industry. It contains physical information on an IC technology such as metal layers, vias, and sites. It also contains descriptions of a number of macros. Since the macros are used during the placement and routing of an IC they have information on the physical layout such as pin and blockage locations. More information on LEF and other collaborative efforts in the EDA industry can be found on Si2.

Download LEF View from addons.mozilla.org


Not that many yet so the list includes some pretty obvious ones :-)


LEF View 0.6 for Firefox 3.5
I have updated LEF View 0.6 on addons.mozilla.org to allow installation in Firefox 3.5. Now that you do not need to create an account on addons.mozilla.org to download extensions from the sandbox I have decided to redirect you there for downloading LEF View.
LEF View 0.6
  • Added support for POLYGON statements in pins and obstructions (blockages)
  • Fixed bug with toggling 'pin' and 'obs' types
  • Made tool tips work (in Firefox 3.0+ only - please update) when hovering over pins and blockages
  • I am making LEF View available both from this web page and addons.mozilla.org. LEF View will probably never make it out of the sandbox and by installing from this page you don't have to sign up for an account on addons.mozilla.org. Automatic updates should work for methods
LEF View 0.5
  • Fixed a Linux bug where the demo.lef file would not load on when clicking the Demo button
  • I have uploaded LEF View on addons.mozilla.org (in the sandbox for now) so that you may install from there if you like
LEF View 0.4
  • Added support for customizing colors for metal layers
  • Added support for displaying regular via definitions from the LEF file
  • Updated extension maxVersion to allow LEF View to run in Firefox 3.0 betas (I will do another release once Firefox 3 goes final)
LEF View 0.3
  • Fixed loading of new LEF files
  • Added support for panning
  • Added support for toggling pin and blockage visibility
  • Added coordinate display
  • Bumped maxversion to allow LEF View to run in Firefox 2.0 (when it becomes available)
LEF View 0.2
  • Fixed a few bugs related to zooming
  • Added support for zooming out
LEF View 0.1
  • Initial release


Lots of things I guess - if you would like to see other features than what is listed below feel free to send me an e-mail.

In no particular order