A 0.2 V, 23 nW CMOS Temperature Sensor for Ultra-Low-Power IoT Applications
AbstractWe propose a fully on-chip CMOS temperature sensor in which a sub-threshold (sub-VT) proportional-to-absolute-temperature (PTAT) current element starves a current-controlled oscillator (CCO). Sub-VT design enables ultra-low-power operation of this temperature sensor. However, such circuits are highly sensitive to process variations, thereby causing varying circuit currents from die to die. We propose a bit-weighted current mirror (BWCM) architecture to resist the effect of process-induced variation in the PTAT current. The analog core constituting the PTAT, the CCO, and the BWCM is operational down to 0.2 V supply voltage. A digital block operational at 0.5 V converts the temperature information into a digital code that can be processed and used by other components in a system-on-chip (SoC). The proposed temperature sensor system also supports resolution-power trade-off for Internet-of-things (IoT) applications with different sampling rates and energy needs. The system power consumption is 23 nW and the maximum temperature inaccuracy is +1.5/−1.7 °C from 0 °C to 100 °C with a two-point calibration. The temperature sensor system was designed in a 130 nm CMOS technology and its total area is 250 × 250 μm2. View Full-Text
Share & Cite This Article
Akella Kamakshi, D.; Shrivastava, A.; Calhoun, B.H. A 0.2 V, 23 nW CMOS Temperature Sensor for Ultra-Low-Power IoT Applications. J. Low Power Electron. Appl. 2016, 6, 10.
Akella Kamakshi D, Shrivastava A, Calhoun BH. A 0.2 V, 23 nW CMOS Temperature Sensor for Ultra-Low-Power IoT Applications. Journal of Low Power Electronics and Applications. 2016; 6(2):10.Chicago/Turabian Style
Akella Kamakshi, Divya; Shrivastava, Aatmesh; Calhoun, Benton H. 2016. "A 0.2 V, 23 nW CMOS Temperature Sensor for Ultra-Low-Power IoT Applications." J. Low Power Electron. Appl. 6, no. 2: 10.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.