VSD Open On-Chip Clock Multiplier (PLL) on OSU180

This repo contains documentation of the "VSD Open On-Chip Clock Multiplier (PLL) on OSU180" tutorial.

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Contents

• Introduction
• Block Diagram of PLL
• Literature review and architecture design theory points
• Theory and Fundamental Concepts
• Setting up Linux Environment
• Installations
  • Git
  • eSim
  • Magic
• Running eSim and Ngspice
  • eSim Schematic of inverter example
  • Running Ngspice
  • Output Waveforms
• Prelayout
  • PFD Design
  • Charge Pump
  • VCO
  • freq_div
  • PLL Prelayout
• Physical Design
  • Layout of Inverter
  • Layout of PFD
  • Layout of VCO
  • Layout of FreqDiv2
  • Layout of FreqDiv8
  • Layout of mux21
  • Final Layout of PLL
• Acknowlegment
• References

Introduction

The phase locked loop take in a signal to which it locks and can then output this signal from its own internal VCO. At first sight this may not appear particularly useful, but with a little ingenuity, it is possible to develop a large number of phase locked loop applications.

Block Diagram of PLL

Literature review and architecture design theory points

1. Design of Analog CMOS Integrated Circuits Behzad Razavi
2. Design of CMOS Phase Locked Loops Behzad Razavi

Theory and Fundamental Concepts

1. CMOS and Transistor Sizing
2. Control System Feedback Loop
3. IC Fab process
4. Euler path

Setting up Linux Environment

Download the latest version of Virtual Box from the following link: https://www.virtualbox.org/ After installation it will look somewhat like this: Download the Ubuntu Disk Image: https://ubuntu.com/download/desktop Create a new machine: Follow the steps hereafter.

After complete installation the Ubuntu window looks like this:

Installations

Git

Open terminal and run:

sudo apt-get install git

Then do:

git clone https://github.com/parasgidd/avsdpll_3v3.git

eSim

Install eSim and follow steps from here: https://esim.fossee.in/downloads

Magic

Run following Commands in the terminal: git clone git://opencircuitdesign.com/magic

cd magic
sudo ./configure
sudo make
sudo make install

Running eSim and Ngspice

eSim Schematic of inverter example

Running Ngspice

cd /avsdpll_3v3/prelayout$
ngspice inv.cir

Output Waveforms

Prelayout

PFD Design

Charge Pump

VCO

freq_div

PLL Prelayout

Physical Design

Layout of Inverter

Run the following command to open Magic:

magic -T SCN6M_SUBM.10.tech

Layout of PFD

Layout of VCO

Layout of FreqDiv2

Layout of FreqDiv8

Layout of mux21

Final Layout of PLL

Acknowlegment

I would like to thank Mr.Kunal Ghosh and Mr. Paras Gidd for the tutorial explained in the simplest way possible. It helped me to learn more about the PLL and layout design and simulations using Magic and Ngspice in a very easy and structured manner.

References

1. https://www.vlsisystemdesign.com/registration/
   
2. https://vsdiat.com/
   
3. https://github.com/parasgidd/avsdpll_3v3
   
4. https://www.virtualbox.org/
   
5. http://opencircuitdesign.com/magic/download.html
   
6. https://esim.fossee.in/downloads
   
7. https://www.electronics-notes.com/articles/radio/pll-phase-locked-loop/tutorial-primer-basics.php