Datasheet
Revised 10/12
5
TECHNICAL INFORMATION FOR TGS2620
0.1
1
10
-20 -10 0 10 20 30 40 50
35%
50%
65%
96%
Rs/Ro
Ambient temperature (˚C)
Gas: 300ppm Ethanol
RH%:
0.1
1
10
100 1000
-10˚C
20˚C/65%RH
40˚C/96%RH
Rs/Ro
Gas concentration (ppm)
2-2 Temperature and humidity dependency
Figure 6 shows the temperature and humidity
dependency of TGS2620. The Y-axis shows the ratio
of sensor resistance in 300ppm of ethanol under
various atmospheric conditions (Rs) to the sensor
resistance in 300ppm of ethanol at 20˚C/65%RH
(Ro).
Fig. 6 - Temperature and humidity dependency (Rs/Ro)
Fig. 7 - Resistance change ratio
under various ambient conditions
Table 1 - Temperature and humidity dependency
(typical values of Rs/Ro for Fig. 6)
Table 1 shows a table of values of the sensor’s
resistance ratio (Rs/Ro) under the same conditions
as those used to generate Figure 6.
Figure 7 shows the sensitivity curve for TGS2620
to ethanol under several ambient conditions. While
temperature may have a large inuence on absolute
Rs values, this chart illustrates the fact that the effect
on the slope of the sensor resistance ratio (Rs/Ro) is
not signicant. As a result, the effects of temperature
on the sensor can easily be compensated.
For economical circuit design, a thermistor can be
incorporated to compensate for temperature (for
additional information on temperature compensation in
circuit designs, please refer to the Technical Advisory
‘Technical Information on Usage of TGS Sensors for Toxic
and Explosive Gas Leak Detectors’).
RH
(˚C)
35%RH 50%RH 65%RH 95%RH
-10 1.80
0 1.72 1.35
10 1.48 1.30 0.96
20 1.37 1.20 1.00 0.75
30 1.04 0.88 0.74 0.63
40 0.85 0.73 0.62 0.57