A sub-μ W embedded CMOS temperature sensor for RFID food monitoring application

Man Kay Law, Amine Bermak, Howard C. Luong

Research output: Contribution to journalArticle

147 Citations (Scopus)


An ultra-low power embedded CMOS temperature sensor based on serially connected subthreshold MOS operation is implemented in a 0.18 μm CMOS process for passive RFID food monitoring applications. Employing serially connected subthreshold MOS as sensing element enables reduced minimum supply voltage for further power reduction, which is of utmost importance in passive RFID applications. Both proportional-to-absolute-temperature (PTAT) and complimentary-to-absolute-temperature (CTAT) signals can be obtained through proper transistor sizing. With the sensor core working under 0.5 V and digital interfacing under 1 V, the sensor dissipates a measured total power of 119 nW at 333 samples/s and achieves an inaccuracy of +1/-0.8 °C from - 10°C to 30°C after calibration. The sensor is embedded inside the fabricated passive UHF RFID tag. Measurement of the sensor performance at the system level is also carried out, illustrating proper sensing operation for passive RFID applications.

Original languageEnglish
Article number5482527
Pages (from-to)1246-1255
Number of pages10
JournalIEEE Journal of Solid-State Circuits
Issue number6
Publication statusPublished - 1 Jun 2010



  • CMOS temperature sensor
  • Embedded sensor
  • Passive RFID tag
  • Ultra-low-power application

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

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