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An Area-Efficient Time-Shared 10b DAC for AMOLED Column Driver IC Applications
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 Title & Authors
An Area-Efficient Time-Shared 10b DAC for AMOLED Column Driver IC Applications
Kim, Won-Kang; An, Tai-Ji; Lee, Seung-Hoon;
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 Abstract
This work proposes a time-shared 10b DAC based on a two-step resistor string to minimize the effective area of a DAC channel for driving each AMOLED display column. The proposed DAC shows a lower effective DAC area per unit column driver and a faster conversion speed than the conventional DACs by employing a time-shared DEMUX and a ROM-based two-step decoder of 6b and 4b in the first and second resistor string. In the second-stage 4b floating resistor string, a simple current source rather than a unity-gain buffer decreases the loading effect and chip area of a DAC channel and eliminates offset mismatch between channels caused by buffer amplifiers. The proposed 1-to-24 DEMUX enables a single DAC channel to drive 24 columns sequentially with a single-phase clock and a 5b binary counter. A 0.9pF sampling capacitor and a small-sized source follower in the input stage of each column-driving buffer amplifier decrease the effect due to channel charge injection and improve the output settling accuracy of the buffer amplifier while using the top-plate sampling scheme in the proposed DAC. The proposed DAC in a CMOS shows a signal settling time of 62.5ns during code transitions from `` to ``. The prototype DAC occupies a unit channel area of and an effective unit channel area of while consuming 6.08mW with analog and digital power supplies of 3.3V and 1.8V, respectively.
 Keywords
시분할;디스플레이용 DAC;저항 열 DAC;2단 롬 구조 디코더;다중 컬럼 구동;
 Language
Korean
 Cited by
 References
1.
K. Yoneda, R. Yokoyama, and T. Yamada, "Development Trends of LTPS TFT LCDs for Mobile Applications," in Symp. VLSI Circuits Dig. Tech. Papers, pp. 85-90, June 2001.

2.
K. M. Kim, et al, "One-Chip Driver IC for 16 Million Color WXGA LTPS TFT LCD Panel," in SID Symposium Dig. Tech. Papers, May 2008, vol. 39, no. 1, pp. 1391-1393.

3.
C. W Lu, C. C. Shen and W. C. Chen, "An Area-Efficient Fully R-DAC-Based TFT-LCD Column Driver," IEEE TCAS I: Regular Papers, vol. 57, no. 10, pp. 2588-2601, Oct. 2010.

4.
J. H. Kim, B. D. Choi, and O. K. Kwon, "1-billion-color TFT LCD TV with full HD format," IEEE Trans. Consumer Electronics, vol. 51, no. 4, pp. 1042-1050, Nov. 2005. crossref(new window)

5.
J. S. Shim, B. D. Choi, "Design of 8-bit DAC for TFT-LCD Data Driver ICs: Trade-off between Speed and Circuit Area," IEEK Fall Conference, pp. 663-666, Nov. 2013.

6.
Y.-C. Sung, S.-M. So, J.-K. Kim, and O.-K. Kwon, "10bit Source Driver with ResistorResistor-String Digital to Analog Converter," in SID Symp. Dig. Tech. Papers, Jun. 2005, pp. 1099-1101.

7.
M. J. Bell, "An LCD column driver using a switch capacitor DAC," IEEE J. Solid-State Circuits, vol. 40, no. 12, pp. 2756-2765, Dec. 2005. crossref(new window)

8.
Y.-J. Jeon, H.-M. Lee, S.-W. Lee, G.-H. Cho, H.-R. Kim, Y.-K. Choi, and M. Lee, "A Piecewise Linear 10 Bit DAC Architecture With Drain Current Modulation for Compact LCD Driver ICs," IEEE J. Solid-State Circuits, vol. 44, no. 12, pp. 3659-3675, Dec. 2009. crossref(new window)

9.
C.-W. Lu, C.-M. Hsiao, and P.-Y. Yin, "A 10-b Two-Stage DAC with an Area-Efficient Multiple-Output Voltage Selector and a Linearity-Enhanced DAC-Embedded Op-Amp for LCD Column Driver ICs," IEEE J. Solid- State Circuits, vol. 48, no. 6, pp. 1475-1486, Jun. 2013. crossref(new window)

10.
K.-D. Kim, et al, "A 10-bit Linear R-string DAC Architecture for Mobile Full-HD AMOLED Driver ICs," in SID Symposium Dig. Tech. Papers, June 2013, vol. 44, no. 1, pp. 469-472.

11.
C.-W. Lu, P.-Y. Yin, C.-M. Hsiao, and M.-C. F. Chang, "A 10b Resistor-Resistor-String DAC with Current Compensation for Compact LCD Driver ICs," in ISSCC Dig. Tech. Papers, pp. 318-320, Feb. 2011.

12.
C.-W. Lu, P.-Y. Yin, C.-M. Hsiao, M.-C. F. Chang, and Y.-S. Lin, "A 10-bit ResistorFloating -Resistor-String DAC (RFR-DAC) for High Color-Depth LCD Driver ICs," IEEE J. Solid-State Circuits, vol. 47, no. 10, pp. 2454-2466, Oct. 2012. crossref(new window)

13.
R. Hogervorst, et al., "A Compact PowerEfficient 3V CMOS Rail-to-Rail Input/ Output Operational Amplifier for VLSI Cell Libraries," IEEE J. Solid-State Circuits, vol. 29, no. 12, pp. 1505-1513, Dec. 1994. crossref(new window)

14.
Y.-J. Kim, H.-C. Choi, G.-C. Ahn, and S.-H. Lee, "A 12b 50 MS/s CMOS Nyquist A/D converter with a fully differential class-AB switched op-amp," IEEE J. Solid-State Circuits, vol. 45, no. 3, pp. 620-628, Mar. 2010. crossref(new window)

15.
C. D. Kim, J. Y. Han, Y. W. Kim, N. J. Song, M. W. Ha, S. H. Lee, "A 1280-RGB x 800-Dot Driver based on 1:12 MUX for 16M-Color LTPS TFT-LCD Displays," Journal of the Institute of Electronics and Information Engineers, vol. 46, SD, no. 1, pp. 98-106, Jan. 2009.

16.
H.-S. Kim, J.-H. Yang, S.-H. Park, S.-T. Ryu, and G.-H. Cho, "A 10-Bit Column-Driver IC With Parasitic-Insensitive Iterative Charge-Sharing Based Capacitor-String Interpolation for Mobile Active-Matrix LCDs," IEEE J. Solid-State Circuits, vol. 49, no. 3, pp. 766-782, Mar. 2014. crossref(new window)