A passive RFID tag embedded temperature sensor with improved process spreads immunity for a-30̂C to 60̂C sensing range

Bo Wang, Man Kay Law, Amine Bermak, Howard C. Luong

Research output: Contribution to journalArticle

43 Citations (Scopus)


We present an ultra-low power temperature sensor embedded in the passive RFID tag using the TSMC 1P6M 0.18 μm m standard CMOS process. Substrate parasitic NPN bipolar pair is exploited to generate the temperature dependent current signals for thermal sensing. A time-domain readout scheme which has high immunity to the on-chip resistor, capacitor and clock frequency process-voltage-temperature (PVT) spreads is further proposed. Measurement results of the embedded sensor within the tag system shows a sensing accuracy of pm 1.5̂C (3σ) from-30̂C to 60̂C after one-point calibration at 20̂C, with a sensing resolution of 0.3̂C and a sampling rate of 68 samples per second. The embedded sensor draws 0.35 μA from a 1 V supply at room temperature and occupies a chip area of 0.14 mm2.

Original languageEnglish
Article number6583328
Pages (from-to)337-346
Number of pages10
JournalIEEE Transactions on Circuits and Systems I: Regular Papers
Issue number2
Publication statusPublished - Feb 2014
Externally publishedYes



  • CMOS temperature sensors
  • passive RFID tags
  • process compensation
  • time-domain conversion (TDC)

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

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