A digital vision sensor with pixel level Analog-to-Digital converter

Amine Bermak, Abdesselam Bouzerdoum, Kamran Eshraghian

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

In this paper we propose an on-pixel Analog-to-Digital converter based on pulse frequency modulation (PFM) scheme. This PFM based converter presents a very viable solution for pixel level based ADC. It uses a very simple and robust circuit that can be implemented in a compact area resulting in a 23% fill-factor. The low-light performance of the PFM converter is improved by using a wider counting period. By modifying the counting period, it is possible to change the saturation level of the ADC and hence improve the dynamic range of the sensor. Image lag is eliminated in the PFM On-pixel ADC since a reset of the photodetector is performed after the conversion period. In addition, the PFM on-pixel ADC has a very important advantage: it is insensitive to variations of the supply and reference voltages. The pixel based ADC has been designed and fabricated using CMOS 0.25 μm technology.

Original languageEnglish
Pages (from-to)353-358
Number of pages6
JournalProceedings of SPIE - The International Society for Optical Engineering
Volume4591
DOIs
Publication statusPublished - 2001
Externally publishedYes

Fingerprint

pulse frequency modulation
Pulse time modulation
Analog-to-digital Converter
Frequency Modulation
analog to digital converters
Digital to analog conversion
Pixel
Pixels
pixels
Sensor
sensors
Sensors
Converter
converters
Counting
counting
Photodetector
Dynamic Range
Photodetectors
dynamic range

Keywords

  • Analog-to-digital converter
  • CMOS image sensors
  • Vision chips

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Condensed Matter Physics

Cite this

A digital vision sensor with pixel level Analog-to-Digital converter. / Bermak, Amine; Bouzerdoum, Abdesselam; Eshraghian, Kamran.

In: Proceedings of SPIE - The International Society for Optical Engineering, Vol. 4591, 2001, p. 353-358.

Research output: Contribution to journalArticle

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