MICS-5131 Datasheet, PDF (3/5 Pages) List of Unclassifed Manufacturers – Ethanol Gas Sensor

MicroChemical Systems
PRODUCT DATA SHEET
Cross Sensitivity:
The following figure illustrates the MiCS-5131 cross
sensitivity to CH4, CO, C2H5OH and H2.
1
0.1
10
CH4
CO
C2H5OH
H2
100
concentration [ppm]
1000
Fig. 4: Sensitivity to CO, H2, CH4, and C2H5OH at
25°C and 50% RH.
Temperature and Humidity
dependence:
Temperature and humidity also affect the resistance value
of the sensor. Humidity is water (H2O) in gas phase, which
reacts with the sensing layer like a reducing gas.
Increasing humidity causes a decrease of the sensing
resistance. As for the temperature, the effect is the same
as for the humidity, i.e. decreasing resistance with
increasing temperature. This negative temperature
coefficient is due to the semiconductor properties of the
sensing layer material.
10
Rs/Ro 20%
Rs/Ro 50%
Rs/Ro 70%
Rs/Ro 90%
1
Response time:
A typical response curve under laboratory conditions is
shown in figure 5. The test gas is 60ppm of C2H5OH and
the sensing resistance reaches 90% of its final change in
about one second.
1.2
1
0.8
0.6
0.4
0.2
0
-10
-5
0
5
10
time [second]
Fig. 5: Response time to 60ppm C2H5OH
0.1
0
20
40
60
80
Temperature [°C]
Fig. 6: Temperature dependence of baseline
resistance Rair for 20%, 50%, 70% and 90% RH.
MiCS-5131 Product Data Sheet
Page 3 of 5
Doc NO: 0178 Rev. B