A Packaged Multiplexed Fluorescent Biomolecular Sensor Array and Ultralow-Power Wireless Interface in CMOS for Ingestible Electronic Applications
Chengjie Zhu, Lingyu Hong, Haw Yang, Kaushik Sengupta
Abstract
Ingestible electronics capable of laboratory quality biomolecular analysis occupying pill-sized volume, operating at sub-mW with a robust wireless interface can transform medical diagnostics and personalized healthcare. Miniaturization of complex biomolecular systems in such a volume is extremely challenging, including a wireless interface that is capable of robust communication through inches of tissue. This article presents for the first time a fully packaged biosensor system with transmitter (Tx)/receiver (Rx) antennas coupled to a single CMOS chip that integrates a low-power wireless interface and a 15-pixel fluorescence biosensor array with on-chip nanoplasmonic optical filters. The IC, operating across multiple industrial, scientific, and medical (ISM)/medical implant communication system (MICS) bands, employs pulse-pause-encoded ASK/OOK modulation, and achieves reception energy efficiency of 28 pJ/bit at 7 Mb/s and −58 dBm of sensitivity with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$196 \mu \text{W}$ </tex-math></inline-formula> of dc power. The entire biocompatible package is miniaturized to a size of 1.2 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times $ </tex-math></inline-formula> 2.5 cm2. To the best of the authors’ knowledge, this work demonstrates for the first time a packaged bio-pill with in situ biomolecular sensing and quantification with pM sensitivity in CMOS ICs that also encompasses wireless transmission capability through inches of tissue at state-of-the-art energy efficiency.