Boosted readout for CMOS APS pixels

In order to reduce power consumption and improve low-voltage operation capability of standard three transistor (3T) CMOS active pixel sensor (APS), new pixel readout is proposed utilizing supply boosting technique (SBT). Pixel supply voltage as well as reset and select signals for APS pixel are boosted to achieve wider and extended linear operating range in a standard CMOS process with high-Vt transistors. Reset and supply boosting was used for extending dynamic range of the pixel source follower (PSF) amplifier, while the select signal boosting was utilized for linearizing transfer characteristics of the PSF. Extension of PSF dynamic range using reset, select, and supply boosting (RSSB) resulted in operation of 3T APS pixel at 1.2V supply with 150mV dynamic range even though the threshold of the NMOS device was 0.8V. Proposed method does not degrade the device reliability margins and use single supply input.

[1]  Suat U. Ay.  A sub-1 Volt 10-bit supply boosted SAR ADC design in standard CMOS , 2011 .

[2]  Ralph Etienne-Cummings,et al.  A 1V current-mode CMOS active pixel sensor , 2005, 2005 IEEE International Symposium on Circuits and Systems.

[3]  Sergio Pernici,et al.  Low-voltage double-sampled ΣΔ converters , 1997 .

[4]  Mansun Chan,et al.  A 1.0 V V/sub DD/ CMOS active pixel image sensor with complementary pixel architecture fabricated with a 0.25 /spl mu/m CMOS process , 2002, 2002 IEEE International Solid-State Circuits Conference. Digest of Technical Papers (Cat. No.02CH37315).

[5]  S.U. Ay,et al.  Electrical property modelling of photodiode type CMOS active pixel sensor (APS) , 2005, 48th Midwest Symposium on Circuits and Systems, 2005..

[6]  E.R. Fossum,et al.  A 1.2 V micropower CMOS active pixel image sensor for portable applications , 2000, 2000 IEEE International Solid-State Circuits Conference. Digest of Technical Papers (Cat. No.00CH37056).

[7]  Suat U. Ay,et al.  Supply boosting technique for designing very low-voltage mixed-signal circuits in standard CMOS , 2010, 2010 53rd IEEE International Midwest Symposium on Circuits and Systems.

[8]  P. Agnello,et al.  CMOS active pixel image sensors fabricated using a 1.8 V, 0.25 /spl mu/m CMOS technology , 1996, International Electron Devices Meeting. Technical Digest.

[9]  Jan Van der Spiegel,et al.  Linear Current-Mode Active Pixel Sensor , 2007, IEEE Journal of Solid-State Circuits.

[10]  P. Agnello,et al.  CMOS active pixel image sensors fabricated using a 1.8 V, 0.25 /spl mu/m CMOS technology , 1996 .

[11]  Hae-Seung Lee,et al.  A 3MPixel Low-Noise Flexible Architecture CMOS Image Sensor , 2006, 2006 IEEE International Solid State Circuits Conference - Digest of Technical Papers.

[12]  M. Chan,et al.  A low voltage hybrid bulk/SOI CMOS active pixel image sensor , 2001, IEEE Electron Device Letters.

[13]  Hwang-Cherng Chow,et al.  A new rail-to-rail readout circuit of CMOS image sensor for low power applications , 2005, 48th Midwest Symposium on Circuits and Systems, 2005..