Low-Noise In-Pixel Comparing Active Pixel Sensor Using Column-Level Single-Slope ADC

A conventional active pixel sensor (APS) uses a source follower (SF) in a pixel as a buffer. This SF is one of the major causes of nonlinearity, sensitivity degradation, and pixel readout noise. The proposed in-pixel comparing APS uses pixel transistors as a part of comparator for a single-slope ADC instead of using them as an SF. The prototype sensor was fabricated using a 0.35-mum 2P3M CMOS process. Experimental results show 15-times linearity improvement, 26% sensitivity enhancement, and 33% noise reduction over the conventional APS.

[1]  Bedabrata Pain,et al.  Optimization of noise and responsivity in CMOS active pixel sensors for detection of ultralow-light levels , 1997, Electronic Imaging.

[2]  A. Krymski,et al.  A 2 e-Noise 1 . 3 Megapixel CMOS Sensor , 2003 .

[3]  I. Takayanagi,et al.  A 1.25-inch 60-frames/s 8.3-M-pixel digital-output CMOS image sensor , 2005, IEEE Journal of Solid-State Circuits.

[4]  B. S. Carlson,et al.  Comparison of modern CCD and CMOS image sensor technologies and systems for low resolution imaging , 2002, Proceedings of IEEE Sensors.

[5]  S. Watanabe,et al.  A 1/1.8-inch 6.4 MPixel 60 frames/s CMOS Image Sensor With Seamless Mode Change , 2006, IEEE Journal of Solid-State Circuits.

[6]  K. Azadet,et al.  A 200 mW 3.3 V CMOS color camera IC producing 352/spl times/288 24 b video at 30 frames/s , 1998, 1998 IEEE International Solid-State Circuits Conference. Digest of Technical Papers, ISSCC. First Edition (Cat. No.98CH36156).

[7]  E. Fossum,et al.  CMOS active pixel image sensors for highly integrated imaging systems , 1997, IEEE J. Solid State Circuits.

[8]  Abbas El Gamal,et al.  Analysis of temporal noise in CMOS photodiode active pixel sensor , 2001, IEEE J. Solid State Circuits.

[9]  Bryan D. Ackland,et al.  A 200-mW, 3.3-V, CMOS Color Camera IC Producing 352 288 24-b Video at 30 Frames/s , 1998 .

[10]  Chuan Yi Tang,et al.  A 2.|E|-Bit Distributed Algorithm for the Directed Euler Trail Problem , 1993, Inf. Process. Lett..

[11]  Y. Tadokoro,et al.  A High-Sensitivity Oversampling Digital Signal Detection Technique for CMOS Image Sensors Using Non-destructive Intermediate High-Speed Readout Mode , 2008 .

[12]  Jeffrey J. Zarnowski,et al.  1.5-FET-per-pixel standard CMOS active column sensor , 1999, Electronic Imaging.

[13]  Chih-Cheng Hsieh,et al.  Focal-plane-arrays and CMOS readout techniques of infrared imaging systems , 1997, IEEE Trans. Circuits Syst. Video Technol..

[14]  T. Yamaguchi,et al.  A 1/4in 2M pixel CMOS image sensor with 1.75 transistor/pixel , 2004, 2004 IEEE International Solid-State Circuits Conference (IEEE Cat. No.04CH37519).

[15]  A. M. Fowler,et al.  Demonstration of an algorithm for read-noise reduction in infrared arrays , 1990 .

[16]  J. P. Lavine,et al.  The pinned photodiode for an interline-transfer CCD image sensor , 1984, 1984 International Electron Devices Meeting.

[17]  S. Kawahito,et al.  A low-noise oversampling signal detection technique for CMOS image sensors , 2002, IMTC/2002. Proceedings of the 19th IEEE Instrumentation and Measurement Technology Conference (IEEE Cat. No.00CH37276).

[18]  Gunhee Han,et al.  A Low Noise and Low Power CMOS Image Sensor with Pixel-level Correlated Double Sampling , 2007, 2007 IEEE Design and Diagnostics of Electronic Circuits and Systems.

[19]  S. Kawahito,et al.  Noise analysis of high-gain, low-noise column readout circuits for CMOS image sensors , 2004, IEEE Transactions on Electron Devices.

[20]  Shoji Kawahito,et al.  A column-based pixel-gain-adaptive CMOS image sensor for low-light-level imaging , 2003, 2003 IEEE International Solid-State Circuits Conference, 2003. Digest of Technical Papers. ISSCC..

[21]  A. Bermak,et al.  A digital pixel sensor array with programmable dynamic range , 2005, IEEE Transactions on Electron Devices.

[22]  Shigeyuki Matsumoto,et al.  A 3.9-μm pixel pitch VGA format 10-b digital output CMOS image sensor with 1.5 transistor/pixel , 2004 .

[23]  S. Watanabe,et al.  A 1/1.8-inch 6.4MPixel 60 frames/s CMOS Image Sensor with Seamless Mode Change , 2006, 2006 IEEE International Solid State Circuits Conference - Digest of Technical Papers.

[24]  Suk Hwan Lim,et al.  A 10,000 Frames/s 0.18 μm CMOS Digital Pixel Sensor with Pixel-Level Memory , 2001 .