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BME 680 TEMPERATURE SENSOR. RUCHEN TANG EDWARD J SHEA SEAN PATRICK SWALVE. OVERVIEW. A small gadget that gives all environmental sensing you want for only $. Thermocouple.
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BME 680 TEMPERATURE SENSOR RUCHEN TANG EDWARD J SHEA SEAN PATRICK SWALVE
OVERVIEW A small gadget that gives all environmental sensing you want for only $
By measuring the voltage difference at the tail end, the device can indirectly get the temperature on the junction end
Resistance Temperature Detectors The resistance of the RTD sensor (usually made of platinum or nickel) changes linearly within their operating temperature range. And the relationship between the resistance and temperature is highly predictable and repeatable
Resistivity follows a predictable linear pattern above certain temperatures • You can find the temperature of a certain area based on this resistance value.
Thermistor Made from semiconductor materials Works basically the same way as RTD Highly nonlinear resistance vs. temperature curve
IC Temperature Sensor · Analog or Digital outputs depending on model · Direct voltage, current or digital output needing no additional circuitry · Nearly linear output with < 1K non-linearity across sensor range · Temperatures directly displayed (1.000 = 100C and 298AµA = 298K or 25°C) on some analog devices
IC Temperature Sensor · Narrow temperature range (commonally 218-423K) · Widely interchangeable compared to RTDs and Thermistors · Large variation in accuracy between different models · Small sizes allow for lower cost and less space taken up inside devices
References • University of Cambridge Department of Material Science and Metallurgy website https://www.msm.cam.ac.uk/utc/thermocouple/pages/ThermocouplesOperatingPrinciples.html • Electronic Project Focus (Elprocus) website https://www.elprocus.com/temperature-sensors-types-working-operation/ • Adafruit BME680 https://learn.adafruit.com/adafruit-bme680-humidity-temperature-barometic-pressure-voc-gas