A time-to-first spike CMOS imager

Author

Qi, Xin ; Guo, Xiaochuan ; Harris, John G.

Author_Institution

Dept. of Electr. & Comput. Eng., Florida Univ., Gainesville, FL, USA

Volume

4

fYear

2004

fDate

23-26 May 2004

Abstract

A novel time-to-first-spike CMOS imager is presented, in which the timing of a single spike from each pixel encodes the illuminance of each pixel. This temporal representation of illuminance can widen the image sensor dynamic range to over 100 dB. To reduce power consumption, an asynchronous address-event readout technique is incorporated. The imager essentially implements a pixel-level A/D conversion and benefits from the continued process scaling to deep submicron levels. Results are shown from a 32×32 pixel imager fabricated in the 0.5 μm AMI process with measured dynamic range of 104 dB in one image. A test chip with one pixel and digital control logic has been fabricated through MOSIS using the TSMC 0.18 μm standard digital CMOS process. It has demonstrated the expected functionalities. A modified architecture is also proposed for a larger imager array.

Keywords

CMOS image sensors; CMOS logic circuits; analogue-digital conversion; integrated circuit design; integrated circuit testing; logic design; 0.18 micron; 0.5 micron; 100 dB; 104 dB; AMI process; CMOS imager; MOSIS; TSMC; asynchronous address-event readout technique; chip testing; continued process scaling; digital control logic; image sensor; imager array; pixel-level A/D conversion; power consumption; standard digital CMOS process; temporal representation; Ambient intelligence; CMOS image sensors; Dynamic range; Energy consumption; Image converters; Image sensors; Logic testing; Pixel; Semiconductor device measurement; Timing;

fLanguage

English

Publisher

ieee

Conference_Titel

Circuits and Systems, 2004. ISCAS '04. Proceedings of the 2004 International Symposium on

Print_ISBN

0-7803-8251-X

Type

conf

DOI

10.1109/ISCAS.2004.1329131

Filename

1329131