A 0.18µm CMOS low-power charge-integration DPS for X-ray imaging

Author

Figueras, Roger ; Sabadell, Justo ; Margarit, Josep Maria ; Martín, Elena ; Terés, Lluís ; Serra-Graells, Francisco

fYear

2009

fDate

26-28 Nov. 2009

Firstpage

209

Lastpage

212

Abstract

This paper presents a new CMOS active pixel sensor specifically for digital X-ray imagers. The proposed DPS architecture includes a novel lossless A/D conversion scheme, a dark current self-cancellation mechanism, as well as self-biasing and built-in test capabilities, all at pixel level. Furthermore, FPN compensation is achieved by introducing gain programmability inside the A/D converter of each individual pixel. The proposed CMOS circuits make extensive use of subthreshold transistor operation and circuit reuse to obtain a low-power and compact DPS cell. A circuit implementation in standard 0.18 μm CMOS 1-polySi 6-metal technology is presented together with experimental preliminary results.

Keywords

CMOS image sensors; X-ray imaging; analogue-digital conversion; built-in self test; diagnostic radiography; image processing; CMOS active pixel sensor; CMOS low-power charge-integration DPS; CMOS polysilicon six-metal technology; FPN compensation; X-ray imaging; built-in test; compact DPS cell; dark current self-cancellation mechanism; digital active pixel sensors; gain programmability; lossless A-D conversion scheme; self-biasing; size 0.18 μm; subthreshold transistor operation; Biomedical imaging; Built-in self-test; CMOS digital integrated circuits; CMOS image sensors; CMOS technology; Crosstalk; Dark current; Pixel; Sensor arrays; X-ray imaging;

fLanguage

English

Publisher

ieee

Conference_Titel

Biomedical Circuits and Systems Conference, 2009. BioCAS 2009. IEEE

Conference_Location

Beijing

Print_ISBN

978-1-4244-4917-0

Electronic_ISBN

978-1-4244-4918-7

Type

conf

DOI

10.1109/BIOCAS.2009.5372046

Filename

5372046