title: Characterization of a CMOS sensing core for ultra-miniature wireless implantable temperature sensors with application to cryomedicine.
abstract: In effort to improve thermal control in minimally invasive cryosurgery, the concept of a miniature, wireless, implantable sensing unit has been developed recently. The sensing unit integrates a wireless power delivery mechanism, wireless communication means, and a sensing core-the subject matter of the current study. The current study presents a CMOS ultra-miniature PTAT temperature sensing core and focuses on design principles, fabrication of a proof-of-concept, and characterization in a cryogenic environment. For this purpose, a 100 μm × 400 μm sensing core prototype has been fabricated using a 130 nm CMOS process. The senor has shown to operate between -180°C and room temperature, to consume power of less than 1 μW, and to have an uncertainty range of 1.4°C and non-linearity of 1.1%. Results of this study suggest that the sensing core is ready to be integrated in the sensing unit, where system integration is the subject matter of a parallel effort.
authors.affiliation: Department of Electrical and Computer Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, United States.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Khairi
authors.affiliation: Department of Mechanical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, United States.
authors.forename: Chandrajit
authors.initials: C
authors.lastname: Thaokar
authors.affiliation: Department of Electrical and Computer Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, United States.
authors.forename: Gary
authors.initials: G
authors.lastname: Fedder
authors.affiliation: Department of Electrical and Computer Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, United States.
authors.forename: Jeyanandh
authors.initials: J
authors.lastname: Paramesh
authors.affiliation: Department of Mechanical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, United States. Electronic address: rabin@cmu.edu.
authors.forename: Yoed
authors.initials: Y
authors.lastname: Rabin
mesh_terms: D000465:Algorithms; D002138:Calibration; D003452:Cryosurgery / Q000295:instrumentation; D017679:Cryotherapy / Q000295:instrumentation; D011211:Electric Power Supplies; D004867:Equipment Design; D017711:Nonlinear Dynamics; D019736:Prostheses and Implants; D015203:Reproducibility of Results; D013696:Temperature; D013821:Thermometers; D059015:Wireless Technology
keywords: All-CMOS; Cryomedicine; Cryosurgery; Implant; Miniature; Temperature sensor; Ultra low-power