On this page you’ll find download links to software that I’ve written.  This includes the latest versions of tools that used to be on the VLSITools website.

GDS Mill

GDS Mill is a free scripting tool for creating, manipulating, and visualizing binary GDS II layout files. It is written in and invoked from object oriented Python. The following features make it stand out as a necessity for anybody steeped in polygons:

  • Read and write BINARY GDS II files
  • Stream in and out to Cadence libraries from within your scripts
  • Create and manipulate all standard layout elements (boundary, path, text, etc.)
  • Perform layer fill operations for density / parasitic constraints
  • Visualize GDS II files in PDF format with custom layer coloring

GDS Mill was developed by Michael Wieckowski during a collaboration between theUniversity of Michigan’s VLSI Design Automation Laboratory and ARM.



How do you characterize SRAM cell stability? What’s the best way to measure mismatch sensitivity of a sense amplifier? How wouldyou determine the effect of wordline boosting on dynamic stability? If you’re like most circuits designers, the answer to these questions would be wrapped upin a collection of scripts handed down and “hacked” repeateadly for every process technology released over the last 20 years.  And if the circuit is anything but astandard six transistor SRAM cell, you might be completely stumped.

Arrows is a Python scripting framework for analyzing ANY type of bi-stable circuit in ANY technology.  It is simple to start using, readilycustomizable and extensible, and easy to read.  Arrows goes beyond just simple SNM and stability analysis. Using its vector field analyzer, its object oriented datamodel, and the power of Python, you can use Arrows to qualify any bistable circuit via dynamic stability measurements, separatrix affinity, or any othermetric you might wish to implement.

Arrows was developed by Michael Wieckowski during a collaboration between theUniversity of Michigan’s VLSI Design Automation Laboratory and ARM.




One Response

  1. Michael Herman · February 19, 2015 at 13:34:57 · →

    Thank you for work…and sharing it with the EE community.
    Your Arrows results give insight to the circuit behavior, missing from the industrial problem of optimization. Moreover, your entire website is well designed, and clear.

    – Michael

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