Design of Stable Reference Voltage Generator and Temperature Sensing System for System Chip Applications

Abstract

Analog and mixed-signal circuits are sensitive to many factors such as the manufacturing process and supply voltage variations In a highly integrated system chip the effect from heat is an important issue which is attracting more and more concern Either the function maintenance in different temperature or the real-time warning of overheat is necessary in a system chip In this dissertation we present a switched-capacitor (SC) charge-mode bandgap reference generator with an improved correlated double sampling (CDS) technique to produce a temperature-insensitive output reference voltage over a wide temperature range By manipulating the CDS technique the circuit only needs a low-gain amplifier to realize the design and thus it is suitable for low-supply-voltage applications For real-time thermal monitoring of all the critical locations in a system-on-a-chip (SoC) a primary-auxiliary temperature sensing scheme is proposed Taking advantage of the high accuracy and linearity of the analog primary temperature sensors and the low production cost of the digital auxiliary temperature sensors this sensing scheme monitors multiple hotspots in a highly integrated system chip with small area and low power consumption A cost efficient calibration strategy based on the difference of calibration complexity and sensitivity to the MOSFET aging between the primary and auxiliary temperature sensors is also presented in this dissertation This calibration strategy can calibrate all the temperature sensors in a thermal monitoring system

Date of Award	2014 Aug 6
Original language	English
Supervisor	Soon-Jyh Chang (Supervisor)