Datasheet
www.sensirion.com Version 0.9 – August 2017 2/15
1 Sensor Performance
1.1 Gas Sensing Performance
Parameter
Signal
Values
Comments
Measurement
range
1
Ethanol signal
0 ppm to 1000 ppm
H
2
signal
0 ppm to 1000 ppm
Specified
measurement
range
Ethanol signal
0.3 ppm to 30 ppm
The specifications below are defined for this measurement
range
2
. The specified measurement range covers the gas
concentrations expected in indoor air quality applications.
H
2
signal
0.5 ppm to 10 ppm
Accuracy
3
Ethanol signal
see Figure 2
typ.: 15% of meas. value
Accuracy of the concentration c
determined by
a = 512
s
out
: EthOH/H
2
signal output
at concentration c
s
ref
: EthOH/H
2
signal output
at 0.5 ppm H
2
c
ref
= 0.4 ppm
H
2
signal
see Figure 3
typ.: 10% of meas. value
c
ref
= 0.5 ppm
Long-term
drift
3,4
Ethanol signal
see Figure 4
typ.: 1.3% of meas. value
Change of accuracy over time: Siloxane accelerated lifetime
test
5
H
2
signal
see Figure 5
typ.: 1.3% of meas. value
Resolution
Ethanol signal
0.2 % of meas. value
Resolution of Ethanol and H
2
signal outputs in relative
change of the measured concentration
H
2
signal
Sampling
frequency
Ethanol signal
Max. 40 Hz
Compare with minimum measurement duration in Table 10
H
2
signal
Table 1 Gas sensing performance. Specifications are at 25°C, 50% RH and typical VDD.
Accuracy ethanol signal
Figure 2 Typical and maximum accuracy tolerance in % of
measured value at 25°C, 50% RH and typical VDD. The sensors
have been operated for at least 24h before the characterization.
Accuracy H
2
signal
Figure 3 Typical and maximum accuracy tolerance in % of
measured value at 25°C, 50% RH and typical VDD. The sensors
have been operated for at least 60h before the characterization.
1
Exposure to ethanol and H
2
concentrations up to 1000 ppm have been tested. For applications requiring the measurement of higher gas
concentrations please contact Sensirion.
2
ppm: parts per million. 1 ppm = 1000 ppb (parts per billion)
3
90% of the sensors will be within the typical accuracy tolerance, >99% are within the maximum tolerance.
4
The long-term drift is stated as change of accuracy per year of operation.
5
Test conditions: operation in 250 ppm Decamethylcyclopentasiloxane (D5) for 200h simulating 10 years of operation in an indoor
environment.