Fundamentals of analog VLSI design

Summary

This course provides the stepping stones to becoming an analog IC designer, from simply understanding the operation of a transistor in a simple circuit context. Students must be familiar with basic transistor/circuit concepts to be introduced to more advanced concepts of analog circuit design spanning across devices, structures, and architectures. The course significantly expands on basic concepts of analog circuit design and introduces fundamentals of device modeling, noise, mismatch. It presents a clear design methodology based on the concept of inversion coefficient. It emphasizes the aspect of low-power consumption and design based on figures-of-merit. It also covers widely-used functional circuit blocks and their design considerations.

Coursebook

You can find more information about this course by looking at the course book.

Books

Device modeling:

CMOS analog IC design:

Gm/ID design methodology:

Tools

Jupyter and Quarto notebooks

The solutions to many exercises will be given in the form a Jupyter or Quarto notebook. We are running Jupyter and Quarto notebooks in Visual Studio Code. Please follow the Jupyter and Quarto installation instructions given in my GitHub Analog Circuit Design repository.

Simulations

The designs are validated with the ngspice (version 4.3) circuit simulator and the EKV 2.6 compact model. Please carefully follow the ngspice installation instructions given in my GitHub Analog Circuit Design repository.

Schematic capture

qucs-s

LTSpice

You can also use LTSpice which includes the EKV v2.6 compact model. However, the thermal noise model is wrong and therefore we prefer using qucs-s. The SC filters are simulated in LTSpice with my special library.

This sections provides examples that will help you checking whether your ngspice, qucs-s and Smash installations work correctly.

The first zip file is a Jupyter Notebook which basically compares the I-V characteristics of nMOS and pMOS obtained from ngspice to those obtained from Smash using the EKV 2.6 compact model for a generic 180nm bulk CMOS process. It also includes a section on noise.

The second zip file is a qucs-s schematic example that plots various characteristics including ID-VG, Gm-VG, ID-VD and Gds-VD characteristics, of nMOS and pMOS transistors from 180nm generic bulk CMOS process. The simulations are ran with ngspice and plotted within qucs-s. You need therefore to have ngspice correctly installed.

The files below give you all the EKV normalized functions that are used for the design of low-power analog circuits using the G_m/I_D approach using the inversion coefficient. You will find the pdf file and the quarto notebook. The python implementation of the EKV normalized functions is found in the ekv_functions.py file.

Contents:

• Course description
• What is circuit design
• Technology roadmap

Slides:

Contents:

• Introduction
• The static model
• The small-signal model
• The noise model
• Transistor matching

Slides:

Contents:

• Introduction
• Velocity saturation (VS)
• Channel length modulation (CLM)
• Drain-induced barrier lowering (DIBL)
• Output conductance in saturation
• Impact of short-channel effects on thermal noise
• The simplified EKV model

Slides:

Contents:

Contents:

• Introduction
• The concept of inversion coefficient
• CS optimization in open-loop configuration
• CS optimization in closed-loop configuration
• Figures-of-merit (FoMs) as design guidelines
• Conclusion

Slides:

Contents

• Current mirrors
• Cascode stage
• Differential pair
• Elementary gain cells and source follower
• Current references
  
  

Contents

• Introduction
• OTA with capacitive feedback
• The simple OTA
• The symmetrical OTA
  
  

Contents:

• Introduction
• Noise sampling
• The autozero (AZ) technique
• The chopper stabilization (CS) technique
• Conclusion
  
  

Contents:

• Introduction
• RC-active filters
• MOSFET-C filters
• Gm-C filters
• Source-follower CTFs
• Noise in CTFs
• Automatic tuning
  
  

Contents:

• Introduction
• Basic principles
• Non-ideal effects in SC circuits
• The design of switched-capacitor filters (SCF)
  
  

Contents:

• Introduction
• General considerations
• The 3-points oscillator
• The cross-coupled pair oscillator