Getting Started with Open-Source CMOS Analog IC Design Toolchain

To begin working with open-source tools for CMOS analog IC design, all you need is a computer and a stable internet connection.

It is recommended to install Linux, as all of the essential tools run smoothly on Linux-based systems. Linux distributions are free, and if you are using Windows, you can easily set up a Linux environment through WSL (Windows Subsystem for Linux). For example, I am using Ubuntu on WSL.

Below are the main tools used in a typical analog IC design flow:

• Schematic Capture:
  xschem — https://xschem.sourceforge.io/stefan/index.html
• Circuit Simulation:
  ngspice — https://ngspice.sourceforge.io
• Layout Editor:
  Magic VLSI — http://opencircuitdesign.com/magic/index.html
• Open PDK:
  SkyWater SKY130 — http://opencircuitdesign.com/open_pdks/index.html

Integrating Xschem with SKY130

There are clear instructions available for setting up xschem with the SKY130 PDK:

Documentation:
XSCHEM SKY130 INTEGRATION

A detailed video tutorial is also available, covering xschem, ngspice, and SKY130 PDK usage from scratch:
https://youtu.be/bYbkz8FXnsQ?si=K5OG5g5v23BnFscz