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(A) process variation tolerant on-chip CMOS thermometer for auto temperature compensated self-refresh of low-power mobile dram : 공정 변화에 둔감한 자동 온도 보상 셀프 리프레쉬용 모바일 디램 온도계
DC Field | Value | Language |
---|---|---|
dc.contributor.advisor | 김수환 | - |
dc.contributor.author | 심대용 | - |
dc.date.accessioned | 2017-07-13T07:00:40Z | - |
dc.date.available | 2017-07-13T07:00:40Z | - |
dc.date.issued | 2013-08 | - |
dc.identifier.other | 000000013960 | - |
dc.identifier.uri | https://hdl.handle.net/10371/118951 | - |
dc.description | 학위논문 (박사)-- 서울대학교 대학원 : 전기·컴퓨터공학부, 2013. 8. 김수환. | - |
dc.description.abstract | Smaller transistors mean that capacitors are charged less uniformly, which increases the self-refresh current in the DRAMs used in mobile devices. Adaptive self-refresh using an on-chip thermometer can solve this problem. In this thesis, a PVT tolerant on-chip CMOS thermometer specifically designed for controlling the refresh period of a DRAM will be proposed for low power mobile DRAM. Two types of on-chip CMOS thermometer including a novel temperature sensor is proposed, which is implemented in two different DRAM process technologies integrated into mobile LPDDR2 and LPDDR3 products. The on-chip thermometer incorporating in mobile LPDDR2 chip is fabricated in a 44nm DRAM process with a supply of 1.1V. The sensor has a temperature sensitivity of −3.2mV/°C, over a range of 0°C to 110°C. Its resolution is 1.94°C and is only limited by the 6.2mV step of the associated resistor ladder not by its own design. The high linearity of the sensor permits one-point calibration, after which the errors in 61 sample circuits ranged between −1.42°C and +2.66°C. The sensor has an active area of 0.001725mm2 and consumes less than 0.36μW on average with a supply of 1.1V.
To improve the overall performance including ultra-low operation voltage, temperature sensitivity, low power consumption, high linearity regardless of process skew variations and high productivity improved by one point calibration, the folded type on-chip thermometer incorporating in mobile LPDDR3 chip which fabricated in a 29nm DRAM process with a supply of 1.1V and 0.8V will be proposed. This folded type sensor exhibits further upgrading properties such as a temperature sensitivity of −3.2mV/°C@1.1V &−3.13mV/°C @0.8V, over wide range of -40°C to 110°C. Its resolution is 1.85°C@1.1V & 1.98°C@0.8V and is only limited by the 6.2mV step. The more linearity of folded type sensor permits one-point calibration, after which the errors in 494 sample circuits ranged between −1.94°C and +1.61°C. The folded type sensor has an active area of 0.001606mm2 and consumes less than 0.19μW@1.1V & 0.14μW@0.8V on average slightly more than unfolded type sensor. | - |
dc.description.tableofcontents | ABSTRACT I
CONTENTS III LIST OF FIGURES V LIST OF TABLES IX CHAPTER 1 INTRODUCTION 1 1.1 MOTIVATION 1 1.2 THESIS ORGANIZATION 3 CHAPTER 2 ARCHITECTURE OF THERMOMETER 5 2.1 INTRODUCTION TO ON-CHIP THERMOMETER IN MOBILE DRAM 5 2.2 PROPOSED ON-CHIP CMOS THERMOMETER ARCHITECTURE 17 2.3 TEMPERATURE READOUT PROCEDURE OF PROPOSED ON-CHIP CMOS THERMOMETER 23 2.4 PROPOSED FOLDED TYPE ON-CHIP CMOS THERMOMETER ARCHITECTURE 25 2.5 TEMPERATURE READOUT PROCEDURE OF PROPOSED FOLDED TYPE ON-CHIP CMOS THERMOMETER 30 2.6 ONE-POINT CALIBRATION METHOD 32 2.7 TEMPERATURE LINEARITY OF TEMPERATURE SENSOR 35 CHAPTER 3 OPERATIONAL PRINCIPLES OF CMOS TEMPERATURE SENSOR IN MOBILE DRAM 39 3.1 PRIOR WORKS OF ON-CHIP THERMOMETER 39 3.2 PROPOSED CMOS TEMPERATURE SENSOR IN MOBILE DRAM 44 3.3 OPERATION PRINCIPLES OF PROPOSED TEMPERATURE SENSOR 48 3.4 PROPOSED FOLDED TYPE TEMPERATURE SENSOR 55 CHAPTER 4 PERIPHERAL CIRCUITS OF THERMOMETER 60 4.1 REGULATOR FOR VLTCSR SUPPLY 61 4.1.1 DC ANALYSIS 62 4.1.2 AC ANALYSIS 63 4.2 RESISTOR DECK 67 4.3 COMPARATOR 68 CHAPTER 5 EXPERIMENTAL RESULTS 70 5.1 ON-CHIP CMOS THERMOMETER IN 44NM CMOS PROCESS FOR MOBILE LPDDR2 74 5.2 FOLDED TYPE ON-CHIP CMOS THERMOMETER IN 29NM CMOS PROCESS FOR MOBILE LPDDR3 77 CHAPTER 6 CONCLUSIONS 83 BIBLIOGRAPHY 86 ABSTRACT IN KOREAN 89 | - |
dc.format | application/pdf | - |
dc.format.extent | 2617466 bytes | - |
dc.format.medium | application/pdf | - |
dc.language.iso | en | - |
dc.publisher | 서울대학교 대학원 | - |
dc.subject | 모바일 디램 | - |
dc.subject | 온도계 | - |
dc.subject | 온도감지기 | - |
dc.subject | 셀프-리프레쉬 | - |
dc.subject | 저전력 | - |
dc.subject.ddc | 621 | - |
dc.title | (A) process variation tolerant on-chip CMOS thermometer for auto temperature compensated self-refresh of low-power mobile dram | - |
dc.title.alternative | 공정 변화에 둔감한 자동 온도 보상 셀프 리프레쉬용 모바일 디램 온도계 | - |
dc.type | Thesis | - |
dc.contributor.AlternativeAuthor | Daeyong Shim | - |
dc.description.degree | Doctor | - |
dc.citation.pages | ix, 90 | - |
dc.contributor.affiliation | 공과대학 전기·컴퓨터공학부 | - |
dc.date.awarded | 2013-08 | - |
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