A system-on-chip EPC Gen-2 passive UHF RFID tag with embedded temperature sensor

Jun Yin, Jun Yi, Man Kay Law, Yunxiao Ling, Man Chiu Lee, Kwok Ping Ng, Bo Gao, Howard C. Luong, Amine Bermak, Mansun Chan, Wing Hung Ki, Chi Ying Tsui, Matthew Yuen

Research output: Contribution to journalArticle

146 Citations (Scopus)


This paper presents a system-on-chip passive RFID tag with an embedded temperature sensor for the EPC Gen-2 protocol in the 900-MHz UHF frequency band. A dual-path clock generator is proposed to support both applications with either very accurate link frequency or very low power consumption. On-chip temperature sensing is accomplished with a time-readout scheme to reduce the power consumption. Moreover, a gain-compensation technique is proposed to reduce the temperature sensing error due to process variations by using the same bandgap reference of the tag to generate bias currents for both the current-to-digital converter and the clock generator of the sensor. Also integrated is a 128-bit one-time-programmable (OTP) memory array based on gate-oxide antifuse without extra mask steps. Fabricated in a standard 0.18- μm CMOS process with analog options, the 1.1-mm2 tag chip is bonded onto an antenna using flip-chip technology to realize a complete tag inlay, which is successfully demonstrated and evaluated in real-time wireless communications with commercial RFID readers. The tag inlay achieves a sensitivity of -6 dBm and a sensing inaccuracy of ±0.8° C (σ inaccuracy) over operating temperature range from -20°C to 30°C with one-point calibration.

Original languageEnglish
Article number5593894
Pages (from-to)2404-2420
Number of pages17
JournalIEEE Journal of Solid-State Circuits
Issue number11
Publication statusPublished - 1 Nov 2010



  • RFID
  • Radio-frequency identification
  • clock
  • energy harvesting
  • injection-locked
  • low power
  • passive tag
  • system-on-chip
  • temperature sensor

ASJC Scopus subject areas

  • Electrical and Electronic Engineering

Cite this

Yin, J., Yi, J., Law, M. K., Ling, Y., Lee, M. C., Ng, K. P., Gao, B., Luong, H. C., Bermak, A., Chan, M., Ki, W. H., Tsui, C. Y., & Yuen, M. (2010). A system-on-chip EPC Gen-2 passive UHF RFID tag with embedded temperature sensor. IEEE Journal of Solid-State Circuits, 45(11), 2404-2420. [5593894]. https://doi.org/10.1109/JSSC.2010.2072631