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FIGARO

PRODUCT INFORMATION

TGS 2180 -

water vapor detection forautomatic control of microwave ovens

Featur es: Applications:

* Low power consumption * High sensitivity to water vapor * High temperature durability * Long life and low cost * Uses simple electrical circuit * Small size * Automatic cooking control inmicrowave ovens

TGS 2180 has relatively high sensitivity to water vapor and low sensitivityto organic vapors which may be generated from cooking food. The sensor's conductivity increases depending on absolute humidity. A simple electrical circuit can convert the change in conductivity to an output signal which corresponds to absolute humidity.Cooking condition can be detected by monitoring changes in sensor resistanceratio, whcih can be uniquely determined depending on the type of food, but independent from the food's weight. With quick response to water vapor and excellent durability in high temperature operation, TGS 2180 is an ideal sensor for automatic cooking time control in microwave ovens.Due to miniaturization of the sensing chip, TGS 2180 requires a heater currentof only 166mA and the device is housed in a standard plastic housing package. The sensing element is comprised of a metal oxide semiconductor layer formed on an alumina substrate of a sensing chip together with an integrated heater. The The figure below represents typical sensitivity characteristics,all data having been gathered at standard test conditions (see reverse side of this sheet). The Y-axis is indicated as The figure below represents sensitivity to various gases. Again, the Y-axis is indicated as sensor resistance ratio (Rs/Ro),defined as follows: sensorresistance ratio (Rs/Ro) which is defined as follows:
Rs = Sensor resistance in vaious concentrationsof gasesRo = Ro = Sensor resistance in clean air at 11.2g/m Rs = Sensor resistance in water vapor at variousabsolute humiditiesRo = Sensor resistance in clean air at 11.2g/m 3 ofabsolute humidity (corresponding to 20ËšC/65%RH) 3 ofabsolute humidity (corresponding to 20ËšC/65%RH) Sensitivity Characteristics to Water Vapor: Sensitivity Characteristics to Various Gases:
Methane Iso-butane Hydrogen CO Ethanol Air Rs/Ro Rs/Ro 0.1 1 1101001000 0.1 1 10 101001000 Absolute humidity (g/m 3 ) Concentration (ppm) IMPORTANT NOTE: OPERATING CONDITIONS IN WHICH FIGARO SENSORS ARE USED WILL VARY WITH EACH CUSTOMER’S SPECIFIC APPLICATIONS. FIGARO STRONGLYRECOMMENDS CONSULTING OUR TECHNICAL STAFF BEFORE DEPLOYING FIGARO SENSORS IN YOUR APPLICATION AND, IN PARTICULAR, WHEN CUSTOMER’S TARGET GASESARE NOT LISTED HEREIN. FIGARO CANNOT ASSUME ANY RESPONSIBILITY FOR ANY USE OF ITS SENSORS IN A PRODUCT OR APPLICATION FOR WHICH SENSOR HAS NOT BEENSPECIFICALLY TESTED BY FIGARO.