CMOS Temperature Sensor with Programmable Temperature Range for Biomedical Applications

Abstract

<div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p class="p1"><span class="s1">A CMOS temperature sensor circuit with programmable temperature range is proposed for biomedical applications. The proposed circuit consists of temperature sensor core circuit and programmable temperature range digital interface circuit. Both circuits are able to be operated at 1.0 V. The proposed temperature sensor circuit is operated in weak inversion region of MOSFETs. The proposed digital interface circuit converts current into time using Current-to-Time Converter (ITC) and converts time to digital data using counter. Temperature range can be programmed by adjusting pulse width of the trigger and clock frequency of counter. The proposed circuit was simulated using HSPICE with 1P, 5M, 3-wells, 0.18-μm CMOS process (BSIM3v3.2, LEVEL53). From the simulation of proposed circuit, temperature range is programmed to be 0 °C to 100 °C, it is obtained that resolution of the proposed circuit is 0.392 °C with -0.89/+0.29 °C inaccuracy and the total power consumption is 22.3 μW in 25 °C.<span class="Apple-converted-space"> </span></span></p></div></div></div>

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

“…The performances of the trimmed thermal sensor ( Figure 3 ) are compared with recently reported digital temperature sensors [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ] in Table 2 . The experimental results of 25 measured DTS samples are in good agreement with the majority of referred data [ 4 , 5 , 6 , 11 , 12 , 13 , 14 , 15 , 18 , 19 , 21 , 24 ], providing low inaccuracy in a wide temperature range.…”

“…Furthermore, the proposed trimmed DTS can be supplied with an extended domain of supply voltages. The presented digital sensor achieves its performance by calibration to just one point, while the inaccuracies obtained in [ 7 , 8 , 9 , 11 , 13 , 18 , 20 , 21 , 22 , 24 ] are performed using the two-point calibration method. With regards to power consumption, the investigated sensor reaches an acceptable value in comparison with [ 11 , 12 , 18 , 22 ].…”

“…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 ].…”

Simple Measurement System for Biological Signal Using a Smartphone

“…In recent years, improving the quality of life and increasing healthspan is become global concern and challenges [1]- [5]. For this reason, management of health on a daily basis is very important, and measuring the own vital data, such as heartbeats, pulses etc, using various equipment are essential.…”