Figaro TGS-2620 gas sensor (Ø x H) 9.2 mm x 7.8 mm TGS-2620 データシート
製品コード
TGS-2620
Revised 10/12
9
TECHNICAL INFORMATION FOR TGS2620
1
10
100
iso-Butane
Methane
Hydrogen
Carbon monoxide
Methyl mercaptan
Hydrogen sulfide
Trimethylamine
Ammonia
Propionic acid
Acetic acid
Acetone
Acetaldehyde
Formaldehyde
Xylene
Toluene
Benzene
n-Heptane
Ethanol
100ppm
1000ppm
1000ppm
Rair/Rgas
30.0
40.0
50.0
60.0
70.0
80.0
90.0
-40
-20
0
20
40
60
80
Heater current (mA)
Ambient temperature (˚C)
inrush current
steady state current
50
45
40
35
30
25
20
15
10
5
0
0
20
40
60
80
100
120
Time (sec.)
V
H
=5V, Ambient temperature=20 C˚
Power on
Heater current - I
H
(mA)
3. Practical Considerations for Circuit Design
3-1 Sensitivity to various organic compounds
Figure 15 shows the sensitivity of TGS2620 to vari-
ous kinds of gases at concentrations of 100ppm and
1000ppm. The x-axis shows the sensitivity ratio of
sensor resistance in clean air (Rair) versus sensor
resistance in the listed gas (Rgas).
Figure 15 shows the sensitivity of TGS2620 to vari-
ous kinds of gases at concentrations of 100ppm and
1000ppm. The x-axis shows the sensitivity ratio of
sensor resistance in clean air (Rair) versus sensor
resistance in the listed gas (Rgas).
This data demonstrates that TGS2620 is an excellent
general purpose sensor for VOCs as it shows good
sensitivity to many kinds of organic compound va-
pors. NOTE: This data is shown only for demonstrating
the high sensitivity of the sensor to VOC’s--never use Rair
as a reference for calibration.
general purpose sensor for VOCs as it shows good
sensitivity to many kinds of organic compound va-
pors. NOTE: This data is shown only for demonstrating
the high sensitivity of the sensor to VOC’s--never use Rair
as a reference for calibration.
3-2 Inrush current of heater
The heater material of the sensor has its own tempera-
ture dependency. Figure 16 shows both the inrush
current and steady state of heater current under
various ambient temperatures for the TGS2620. This
chart illustrates that inrush current is approximately
40% higher than the steady state current. Since heater
resistance shows a lower value at low temperatures,
this would cause a larger than expected current at
room temperature. As a result, when a device using
the sensor is first powered on, an extremely high cur-
rent may be generated during the first few moments
of energizing. Therefore protection from inrush
current should be considered for incorporation into
circuit design.
ture dependency. Figure 16 shows both the inrush
current and steady state of heater current under
various ambient temperatures for the TGS2620. This
chart illustrates that inrush current is approximately
40% higher than the steady state current. Since heater
resistance shows a lower value at low temperatures,
this would cause a larger than expected current at
room temperature. As a result, when a device using
the sensor is first powered on, an extremely high cur-
rent may be generated during the first few moments
of energizing. Therefore protection from inrush
current should be considered for incorporation into
circuit design.
In actual application, it should be noted that the pe-
riod of inrush current would last less than 10 seconds,
after which the heater current reaches to a constant
value as shown in Figure 17.
riod of inrush current would last less than 10 seconds,
after which the heater current reaches to a constant
value as shown in Figure 17.
Fig. 15 - Sensitivity to various organic compounds
Fig. 16 - Temperature dependency of heater current
Fig. 17 - Change in heater current after powering on