# VSD Intern – Analog Bandgap Reference design using Sky130

### Overview

This webinar provides detail about General Purpose Bandgap Reference. The basic working principle of Bandgap reference circuits is explained . The circuit implementation is discussed and the issues with each implementation style is mentioned. Index Terms—Bandgap Reference, CTAT, PTAT, Current mirror, OpAmp.

A Bandgap Reference is a circuit which gives a constant voltage output Vref irrespective of temperature, process and supply voltage variations. It is an especially important component of several analog and mixed signal Integrated Circuits. Several circuits such as LDO, ADC, DAC, Buck convertor. use Bandgap reference as a building block. It provides a constant output reference voltage of 1.2V which is proportional to the Bandgap energy of Silicon(1.2eV)at 0K and hence, gets its name as Bandgap Reference circuit

For detailed information regarding the Bandgap Reference circuit, refer to VLSI System Design website. Below are the details we will be covering in this webinar

1. Performance parameters and Circuit implementation of Bandgap Reference IP
2. Block Diagram and Schematic
4. Pre-Layout Simulation of Bandgap Reference IP circuit using Ngspice
5. Vbgp v/s Temperature [ -40C – 140C] @ RL = 100M ohms plot
6. Vbgp v/s VDD [ 2V – 4V] @ RL = 100M ohms plot
7. Temperature Coefficient of Vbgp v/s Temperature [ -40C – 140C] @ RL = 100M ohms plot
8. Voltage Coefficient of Vbgp v/s VDD [ 2V – 4V] @ RL = 100M ohms plot
9. Start-Up Time of Vbgp @ RL = 100M ohms plot
10. On-Off-Current of Vbgp wrt Enable @ RL = 100M ohms plot
11. BGR Layout using Magic

Hope you enjoy the webinar

### Objective

• Introduction
• Introduction
• CTAT,PTAT and BGR
• Start-up enable and full BGR circuit
• Necessary Opensource EDA tool installation
• Installation of tools – Part 1
• Installation of tools – Part 2
• BGR Circuit design and pre-layout simulation using Sky130
• Writing netlist
• Temperature variation plot – Part 1
• Temperature variation plot – Part 2
• Supply variation plot – Part 1
• Supply variation plot – Part 2
• Pre-layout simulations – Part 1
• Pre-layout simulations – Part 2
• BGR Layout Hierarchies
• Building blocks – Part 1
• Building blocks – Part 2
• Placement of blocks – Part 1
• Placement of blocks – Part 2
• Contacts – Part 1
• Contacts – Part 2
• BGR full layout
• Layout Connections – Part 1
• Layout Connections – Part 2
• Layout Connections – Part 3
• Layout Connections – Part 4
• Layout Connections – Part 5
• Layout Connections – Part 6
• BGR post-layout simulations
• Post-layout simulations – Part 1
• Post-layout simulations – Part 2
• Post-layout simulations – Part 3
• Conclusion

#### Audience Profile

• Beginner electronics and telecommunications engineer looking to enter in analog VLSI domain
• Professional Physical design and SoC designers who are curious to know about Analog IPs used in their designs

#### Prerequisites

• VSD – Circuit design and SPICE simulations
• VSD – Custom Layout

#### What you’ll learn

• Basics of analog VLSI design
• General purpose bandgap reference design using Sky130
Circuit design and layout concepts using Sky130