"A Low-Power Low-Voltage Bandgap Reference in CMOS" by Na Sun

Author

Na Sun

Date of Award

2009

Degree Type

Thesis

Degree Name

Master of Engineering Science

Program

Electrical and Computer Engineering

Supervisor

Dr. Robert Sobot

Abstract

Bandgap reference plays a substantial role in integrated circuit. Traditionally, it provides a constant reference voltage of 1.2051/ for other blocks in the circuit while itself is independent of temperature and power supply. However, the development of CMOS technology has brought us into a new era of high integration and ultra-low power consumption. As the gate length scales down, it is crucial to build circuits that are able to work under a very low voltage power supply, for instance, lower than the bandgap voltage of 1.205V. Building bandgap circuits to generate the conven­ tional bandgap voltage under a low voltage power supply such as 1.2V or IV is no longer practical nor useful. Thus, bandgap references working under low-voltage and consuming low-power is becoming the trend of research and development nowadays.

In this thesis work, the potential structure of a low-voltage low-power bandgap reference is proposed, which is based on extracting a current that is a fraction of the traditional bandgap voltage. All the necessary blocks are designed to achieve the high accuracy bandgap reference, including bandgap core circuit, op-amp, start-up circuit and output stage. As a result, the designed bandgap reference is able to work under 1.2V power supply and provides an output reference voltage of 584.7mV. It has a variation of only 244.38fiV for the temperature range of 0°C ~ 125°C and has a variation of only 1.1mV for a power supply range of 1.08V ~ 1.32V. The layout design for the bandgap reference structure is also done carefully at the late stage, with an area of 100fj,m x 85¡xm.

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.