• Woojun Choi
  • Yongtae Lee
  • Seonhong Kim
  • Sanghoon Lee
  • Jieun Jang
  • Junhyun Chun
  • Kofi A.A. Makinwa
  • Youngcheol Chae

This paper presents a compact resistor-based CMOS temperature sensor intended for dense thermal monitoring. It is based on an RC poly-phase filter (PPF), whose temperature-dependent phase shift is read out by a frequency-locked loop (FLL). The PPF's phase shift is determined by a zero-crossing (ZC) detector, allowing the rest of the FLL to be realized in an area-efficient manner. Implemented in a 65-nm CMOS technology, the sensor occupies only 7000 μm². It can operate from supply voltages as low as 0.85 V and consumes 68 μW. A sensor based on a PPF made from silicided p-poly resistors and metal-insulator-metal (MIM) capacitors achieves an inaccuracy of ±0.12 °C (3σ) from -40 °C to 85 °C and a resolution of 2.5 mK (rms) in a 1-ms conversion time. This corresponds to a resolution figure-of-merit (FoM) of 0.43 pJ·K².

Original languageEnglish
Pages (from-to)3356-3367
Number of pages12
JournalIEEE Journal of Solid-State Circuits
Issue number12
Publication statusPublished - 2018

    Research areas

  • Area-efficient, CMOS temperature sensor, energy-efficient, frequency-locked loop (FLL), poly-phase filter (PPF), resistor-based sensor, trimming, zero-crossing (ZC) detection

ID: 47250120