此篇論文為應用於有機發光二極體顯示器外部補償系統之電流感測電路設計。近年來主動式有機發光二極體顯示器之市場成長快速然而有機發光二極體顯示器的畫素電路之薄膜電晶體會由於製程差異或在長時間的操作下元件老化衰退導致畫素電路內的臨界電壓與電子遷移率產生偏移的現象，除此之外有機發光二極體的也會隨著使用時間產生衰退的現象使得臨界電壓上升，導致致面板顯示品質降低。故本論文提出的電流感測電路將針對畫素電路裡的驅動薄膜電晶體的臨界電壓變化與有機發光二極體的衰退現象進行電性的感測。此外面板的負載會影響電流積分器的電流感測線性度，故在本論文中提出能夠改善電流感測線性度之電流放大器架構與頻率補償方式以增加外部補償系統的精準度。
本感測電路所偵測之畫素電流範圍為-0.5μA~0.5μA，輸入電壓範圍為3V~9V，輸出電壓範圍為0.4V~1.4V，並操作在18V/1.8V工作電壓下，面板等效負載使用五級RC等效方式，分別為五顆串聯的1KΩ電阻與五顆並聯的60pF電容。此電流感測電路，包含將畫素電流轉為電壓的電流積分器、電壓位準轉換器的反向放大器與取樣保持電路，並且使用世界先進積體電路股份有限公司所提供的VIS 0.18µm 1P6M CMOS 高壓製程設計與下線，本晶片共200個通道，整體晶片面積為21125µm×1363.8µm。模擬結果為電流感測電路最小解析度1LSB=0.9765mV，其線性度為INL=0.02LSB、DNL=0.035LSB與Gain error=3.47%.

In this thesis,the current sensing circuit is implemented for an active matrix organic light emitting diode (AMOLED) display external compensatoin system. In recent years, AMOLED displays have developed rapidly. However, the thin-film transistors (TFTs) of AMOLED display pixel circuit threshold voltage and mobility may vary or shift because of either fabrication process variation or long-term operation. Additionally, the threshold voltage of OLED increases due to the degradation of organic materials. Consequently, these problems reduce the image quality of AMOLED displays. The current sensing circuit is proposed in this work which can sense the electrical characteristics of threshold voltage shifts of driving TFTs and OLEDs, to eliminate these issue. Furthermore, the panel loading influence the linearity of current sensing circuit .The novel structure and frequency compensation methods are proposed to solve linearity issue.
The sensing range of the current sensing circuit is -0.5μA~0.5μA , the input common mode voltage is 3V~9V,and the output voltage range is 0.4V~1.4V. The operation voltage is 1.8V/18V. The panel load is emulated in 5-stage RC which series five 1KΩ resistors and parallel five 60pF capacitors.The current sensing circuit includes current integrator which convert current to voltage , level shifter amplifier and S/H circuit.
This chip implemented VIS 0.18µm 1P6M CMOS high voltage process provided by Vanguard International Semiconductor Corporation.This chip includes 200 channels. The die area of this chip is 21125µm×1363.8µm. The 1LSB resolution of current sensing circut is 0.9765mV. The maximum DNL and INL of the current sensing circuit is 0.035LSB and 0.02LSB ,and gain error is 3.47% respectively.

中文摘要 i
Abstract ii
目錄 iii
圖目錄 vi
表目錄 ix
第一章 緒論 1
1.1 研究背景 1
1.2 研究動機 2
1.3 論文架構 4
第二章 有機發光二極體顯示器補償系統簡介 5
2.1 有機發光二極體顯示器簡介 5
2.1.1 有機發光二極體簡介 5
2.1.2 薄膜電晶體製程技術簡介 6
2.2 AMOLED驅動方式探討 6
2.2.1 電壓驅動法(Voltage-Driving Method) 6
2.2.2 電流驅動法(Current-driving method) 7
2.3 AMOLED顯示器補償方式簡介 8
2.3.1 內部補償法(Internal compensation) 9
2.3.2 外部補償法(External Compensation) 10
第三章 外部補償系統讀出電路介紹 13
3.1 電路架構與操作原理 14
3.1.1 重置模式(Reset Phase) 15
3.1.2 積分模式(Integration phase) 17
3.1.3 讀出模式(Readout phase) 18
3.2 讀出電路參數介紹 19
3.2.1 最低有效位元(Least signification bit) 19
3.2.2 微分非線性誤差(Differential Nonlinearity,DNL) 20
3.2.3 積分非線性誤差(Integral Nonlinearity,INL) 21
3.2.4 增益誤差(Gain Error) 22
3.2.5 偏移誤差(Offset Error) 22
第四章 電路實現與設計 23
4.1 應用於積分器電路之運算放大器所需規格 23
4.1.1 運算放大器的精準度考量 23
4.1.2 運算放大器的速度考量 24
4.2 應用於積分器電路之運算放大器架構 25
4.2.1 傳統Class-AB 放大器與Miller cascode補償方式 25
4.2.2 傳統Class-AB 放大器與改良式補償方式 29
4.2.3 改良式Class-AB放大器與改良式Class-AB 放大器 32
4.3 應用於反向放大器之運算放大器 38
4.3.1 運算放大器的精準度考量 38
4.3.2 運算放大器的頻寬 39
4.4 應用於採樣與保持電路之運算放大器 40
4.4.1 運算放大器的精準度考量 40
4.4.2 運算放大器的速度考量 41
4.5 拔靴式開關(Bootstrap Switch) 42
4.6 偏壓電路 43
4.7 時序電路設計 45
第五章 電路模擬結果 47
5.1 子電路模擬 47
5.1.1 應用於積分器電路之運算放大器 47
5.1.2 應用於反向放大器之運算放大器 50
5.1.3 應用於採樣與保持電路之運算放大器 53
5.1.4 電壓位準移位器(Level shifter) 55
5.1.5 時脈產生電路 56
5.2 讀出電路模擬 58
5.2.1 電流積分器電路線性度模擬 58
5.2.2 電流感測電路線性度模擬 60
5.2.3 電路佈局 62
第六章 量測環境架設 64
6.1 量測環境架設 64
第七章 結論與未來展望 66
7.1 結論 66
7.2 未來展望 66
第八章 參考文獻 67

[1]S. Kunić and Z. Šego, "OLED technology and displays," Proceedings ELMAR-2012, Zadar, pp. 31-35, 2012.
[2]Reza Chaji, Arokia Nathan,"Thin film transistor circuits and systems,"Cambridge University Press,2013.
[3]J. J. Lih, C. F. Sung, C. H. Li, T. H. Hsiao, and H. H. Lee, “Invited: comparison of a-Si and poly-Si for AMOLEDs,” in SID Tech. Dig., pp. 1504-1507, 2004.
[4]A. Nathan, G. R. Chaji, and S. J. Ashtiani, “Driving schemes for a-Si and LTPS
AMOLED displays,” IEEE/OSA Journal of Display Technology, vol. 1, no. 2, pp.
267-277, Dec. 2005.
[5]S. H. Jung, W. J. Nam, and M. K. Han, “A new voltage-modulated AMOLED pixel
design compensating for threshold voltage variation in poly-Si TFTs,” IEEE Electron
Device Lett., vol. 25, no. 10, pp. 690-692, Oct. 2004.
[6]M. E. Lopes, H. L. Gomes, M. C. R. Medeiros, P. Barquinha, L. Pereira, E.Fortunato, R. Martins, and I. Ferreira, “Gate-bias stress in amorphous oxidesemiconductors thin-film transistors,” Appl. Phys. Lett., vol. 95, no. 6, pp. 063502,2009.
[7]H. H. Hsieh, T. T. Tsai, C. Y. Chang, H. H. Wang, J. Y. Huang, S. F. Hsu, Y. C. Wu, T.C. Tsai, C. S. Chuang, L. H. Chang, and Y. H. Lin, “A 2.4-in. AMOLED with IGZOTFTs and inverted OLED devices,” in SID Tech. Dig., pp. 140-143, 2010.
[8]A. Nathan, A. Kumar, K. Sakariya, P. Servati, S. Sambandan and D. Striakhilev, "Amorphous silicon thin film transistor circuit integration for organic LED displays on glass and plastic," in IEEE Journal of Solid-State Circuits, vol. 39, no. 9, pp. 1477-1486, Sept. 2004.
[9] R. M. A. Dawson, Z. Shen, D. A. Furest, S. Connor, J. Hsu, M. G. Kane, R.G. Stewart,A. Ipri, C. N. King, P. J. Green, R. T. Flegal, S. Pearson, C.W. Tang, S. Van Slyke, F.Chen, J. Shi, M. H. Lu, and J. C. Sturm, “The impact of the transient response of organic light emitting diodes on the design of active matrix OLED displays,” in IEDM Tech. Dig., pp. 875-878, 1998.
[10] P. E. Burrow, S. R. Forrest, T. X. Zhou, and L. Michalski, “Operating lifetime of phosphorescent organic light emitting devices,” Appl. Phys. Lett., vol. 76, no. 18, pp.
2493-2495, May 2000.
[11] G. R. Chaji, P. Servati and A. Nathan, "Driving scheme for stable operation of 2-TFT a-Si AMOLED pixel," in Electronics Letters, vol. 41, no. 8, pp. 499-500, 14 April 2005.
[12] A. Nathan, G. R. Chaji and S. J. Ashtiani, "Driving schemes for a-Si and LTPS AMOLED displays," in Journal of Display Technology, vol. 1, no. 2, pp. 267-277, Dec. 2005.
[13] Y. Lin and H.-P. D. Shieh, “A novel current memory circuit forAMOLEDs,” IEEE Trans. Electron Devices, vol. 51, no. 6, pp.1037–1040, Jun. 2004.
[14] H.-J. In and O.-K. Kwon, “External compensation of nonuniform electrical characteristics of thin-film transistors and degradation of OLED devices in AMOLED displays,” IEEE Electron. Device Lett., vol. 30, no. 4, pp. 377–379, Apr. 2009.
[15] Tanabe, T., Amano, S., Miyake, H., Suzuki, A., Komatsu, R., Koyama, J., “New Threshold Voltage Compensation Pixel Circuits in 13.5-inch Quad Full High Definition OLED Display of Crystalline In-Ga-Zn-Oxide FETs,” SID Symp. Dig. Tech. Pap,2012
[16] Y.-J. Jeon, J.-Y. Jeon, Y.-S. Son, J. Huh, and G.-H. Cho, “A high-speed current-mode data driver with push-pull transient current feedforward for full-HD AMOLED displays,” IEEE J. Solid-State Circuits, vol. 45, no. 9, pp. 1881–1895, Sep. 2010.
[17] J. Bang et al., "A Hybrid AMOLED Driver IC for Real-Time TFT Nonuniformity Compensation," in IEEE Journal of Solid-State Circuits, vol. 51, no. 4, pp. 966-978, April 2016.
[18] H. In et al., "An Advanced External Compensation System for Active Matrix Organic Light-Emitting Diode Displays With Poly-Si Thin-Film Transistor Backplane," in IEEE Transactions on Electron Devices, vol. 57, no. 11, pp. 3012-3019, Nov. 2010.
[19] G. R. Chaji and A. Nathan, "A Current-Mode Comparator for Digital Calibration of Amorphous Silicon AMOLED Displays," in IEEE Transactions on Circuits and Systems II: Express Briefs, vol. 55, no. 7, pp. 614-618, July 2008.
[20] J.-S. Bang, H.-S. Kim, S.-H. Park, G.-H. Kim, and G.-H. Cho, “A real-time TFT compensation through power line current sensing for high resolution AMOLED displays,” in SID Symp. Dig. Tech. Papers, 2014.
[21] Shunpei Yamazaki, Tetsuo Tsutsui,” Physics and Technology of Crystalline Oxide Semiconductor CAAC-IGZO: Application to Displays,” Wiley Series in Display Technology, pp.280-282, Feb. 2017.