A 32 x 32 ISFET Chemical Sensing Array With Integrated Trapped Charge and Gain Compensation
File(s)
Accepted version
Author(s)
Hu, Y
Moser, N
Georgiou, P
Type
Journal Article
Abstract
This paper presents a CMOS-based 32 × 32 ion-sensitive field-effect transistor (ISFET) system-on-chip for real-time ion imaging. Fabricated in an unmodified 0.35-μm CMOS technology, the ISFET sensor array is based on a pixel topology, which uses capacitive feedback to improve signal attenuation due to passivation capacitance and a low-leakage floatinggate reset followed by a digital correlated double sampling to robustly remove unwanted trapped charge-induced dc offset. An automatic gain calibration (AGC) is used to perform realtime calibration and guarantee all sensors that have the same gain with a 99% accuracy, and combining all these mechanisms guarantees an average pixel voltage variation of 14.3 mV after gain is applied when measured over multiple dies. The full array is experimentally shown to be capable of real-time ion imaging of pH, with an intrinsic sensitivity of 39.6mV/pH and a scan rate of 9.3 frames/s when running the AGC, with a total power consumption of 10.2 mW.
Date Issued
2017-06-30
Date Acceptance
2017-06-17
Citation
IEEE SENSORS JOURNAL, 2017, 17 (16), pp.5276-5284
ISSN
1530-437X
Publisher
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Start Page
5276
End Page
5284
Journal / Book Title
IEEE SENSORS JOURNAL
Volume
17
Issue
16
Copyright Statement
© 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.
Identifier
http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000406310500029&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
Subjects
Science & Technology
Technology
Physical Sciences
Engineering, Electrical & Electronic
Instruments & Instrumentation
Physics, Applied
Engineering
Physics
ISFET
CMOS sensor
sensor array
offset cancellation
automatic gain calibration
pH sensor
FRONT-END
CMOS
SYSTEM
INSTRUMENTATION
CELL
0906 Electrical And Electronic Engineering
0913 Mechanical Engineering
Analytical Chemistry
Publication Status
Published