A 1770-$\mu$ m² Leakage-Based Digital Temperature Sensor With Supply Sensitivity Suppression in 55-nm CMOS

Categorization and Characterization of Time Domain CMOS Temperature Sensors

“…The previously published time domain CMOS temperature sensors in literature [ 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 ] can be categorized into one of the types 3, 4, 5, 7, 8, 11 and 12, respectively, as shown in Figure 4 . In this section, their temperature estimation functions, X(T), are derived first and then characterized as follows.…”

“…Figure 11 shows the architecture of the time domain CMOS temperature sensor published by Y.-S. Lin et al in 2008 [ 34 ]. This architecture was also used by S. Jeong et al and Z. Tang et al in 2014 [ 46 ] and 2020 [ 55 ], respectively. This temperature sensor estimates temperature by counting the number of clock signals generated from the temperature dependent oscillator during the pulse width which is proportional to the temperature independent reference clock period applied from a crystal oscillator.…”

A Digital Improvement—Trimming a Digital Temperature Sensor with EEPROM Reprogrammable Fuses

“…Digital temperature sensors are suitable for thermal and power management systems of PCs, laptops, and smartphones. A low-cost and high-accuracy temperature sensor with a digital interface is desired nowadays due to the high demand for electronic smart gadgets [ 1 , 2 , 3 , 4 ]. Furthermore, the use of temperature detectors with digital output has been recently reported in smart sensor networks, image sensors, Internet of Things devices, and biomedical applications [ 5 , 6 , 7 , 8 , 9 ].…”

A 0.026 mm2 Time Domain CMOS Temperature Sensor with Simple Current Source

“…Due to their small form factor, low power consumption, low cost and convenient digital interface capability, integrated temperature sensor chips have been widely used for thermal monitoring in various smart applications such as the smart farm, smart factory, smart health, and so on. Integrated temperature sensor chips can be implemented in various ways depending on the sensing element which is generally chosen from the threshold voltage, mobility, resistance or thermal voltage; the measured signal type, which is generally chosen from the voltage, current, frequency, or delay time; and the overall architecture which is basically determined by the chosen sensing element and the measured signal type [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 ].…”

“…Among the possible architectures, a time domain architecture based on frequency or delay time is promising because it can benefit from the recent trend that time resolution is being increased while voltage resolution is being decreased as the CMOS channel length and the supply voltage are scaled down. By measuring time domain signals such as the clock frequency, clock period or delay time, an efficient estimate of the current temperature can be obtained [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 ]. The sensing element can be chosen from the mobility, threshold voltage or resistance.…”