臺灣博碩士論文加值系統

本篇論文是以微型處理器陣列與生物晶片為應用，所設計的極低功率溫度感測器。利用漏電流為感測機制，是一個新的溫度感測概念。在此設計當中，採用N井/P高濃度摻雜之二極體來產生需要的漏電流。此外，為了應用方便採用輸出頻率訊號的架構，回授電路將輸出訊號回授至感測電路，藉此控制輸出頻率。內文當中提出分析輸出頻率與溫度的關係，並且建立出數學模型預期輸出結果。
本篇論文提到的溫度感測器，採用TSMC 0.35 μm 2P4M mixed-signal CMOS 製程來實現，每個模型的面積為0.016 mm2 (127.2 μm x 129 μm)，加入pads之後的總面積為1.06 mm2 (0.97nm x 1.1 nm)。當設定時脈速度為每秒10百萬次，總消耗功率在4毫瓦以下。

The goal of this research is to design an extremely low power temperature sensor suitable for microprocessor array and biochip. Using leakage current is a new concept of sensing mechanism. The proposed temperature sensor composed of N-well/P+ diode for generating leakage current. Besides, to perform frequency output for convenience, a feedback element is controlled the sensing element and the output frequency. An expected result of output frequency to temperature was analyzed with mathematical model.
This temperature sensor is to be implemented in a 0.35 μm 2P4M mixed-signal CMOS process provided by TSMC, with each model area of 0.016 mm2 (127.2 μm x 129 μm), and total area including pads is 1.06 mm2 (0.97nm x 1.1 nm). The total power consumption at 10 MHz clock is under 4 μW.

Chapter 1 Introduction 1
1.1 Thesis Motivation 1
1.2 Thesis Organization 2

Chapter 2 Temperature Sensor Architecture 3
2.1 General Background 3
2.2 Current-Output Temperature Sensor 5
2.3 Frequency-Output Temperature Sensor 8
2.4 Clock-Synchronized Temperature Sensor 10
2.5 The Thermal Feedback Oscillator (TFO) Sensor 12
2.6 Leakage Current 14

Chapter 3 Circuit Design Techniques of Temperature Sensor 16
3.1 Overview 16
3.2 Sensing Element 22
3.2.1 Diode 22
3.2.2 Leakage Current 23
Derivation for Leakage Current Density 23
Derivation for Depletion Width and P-N Junction 23
Factors Affecting Leakage Current 30
3.2.3 Leakage Current Collection 31
3.2.4 Temperature & Frequency 32
3.3 Decision Elements 35
3.3.1 Comparator 35
Over-Drive Recovery 40
Resolution 42
3.3.2 D Flip-Flop 43
3.4 Layout Implementation 45

Chapter 4 Simulation Results and Testing Setup 51
4.1 Full Chip Simulation 51
4.2 Experimental Setup 54

Chapter 5 Conclusions 56
5.1 Thesis Contribution 56
5.2 Future Work 56

References 57

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