CMOS direct time interval measurement of long-lived luminescence lifetimes

Lei Yao; Ka Yi Yung; Maurice C Cheung; Vamsy P Chodavarapu; Frank V Bright

doi:10.1109/IEMBS.2011.6089883

CMOS direct time interval measurement of long-lived luminescence lifetimes

Annu Int Conf IEEE Eng Med Biol Soc. 2011:2011:5-9. doi: 10.1109/IEMBS.2011.6089883.

Authors

Lei Yao¹, Ka Yi Yung, Maurice C Cheung, Vamsy P Chodavarapu, Frank V Bright

Affiliation

¹ Department of Electrical and Computer Engineering, McGill University, Montreal, QC H3A2A7, Canada. yaol@ime.a-star.edu.sg

PMID: 22254237
DOI: 10.1109/IEMBS.2011.6089883

Abstract

We describe a Complementary Metal-Oxide Semiconductor (CMOS) Direct Time Interval Measurement (DTIM) Integrated Circuit (IC) to detect the decay (fall) time of the luminescence emission when analyte-sensitive luminophores are excited with an optical pulse. The CMOS DTIM IC includes 14 × 14 phototransistor array, transimpedance amplifier, regulated gain amplifier, fall time detector, and time-to-digital convertor. We examined the DTIM system to measure the emission lifetime of oxygen-sensitive luminophores tris(4,7-diphenyl-1, 10-phenanthroline) ruthenium(II) ([Ru(dpp)(3)](2+)) encapsulated in sol-gel derived xerogel thin-films. The DTIM system fabricated using TSMC 0.35 μm process functions to detect lifetimes from 4 μs to 14.4 μs but can be tuned to detect longer lifetimes. The system provides 8-bit digital output proportional to lifetimes and consumes 4.5 mW of power with 3.3 V DC supply. The CMOS system provides a useful platform for the development of reliable, robust, and miniaturized optical chemical sensors.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Equipment Design
Equipment Failure Analysis
Luminescent Measurements / instrumentation*
Molecular Probe Techniques / instrumentation*
Reproducibility of Results
Semiconductors*
Sensitivity and Specificity