Datasheet

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www.aosong.com Guangzhou Aosong Electronics Co.,Ltd. Tel: [phone] Versior:V1. 0
AM2311A Technical Manual
1 Expansion of performance
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Figure 4 Working Conditions
Temperature (℃)
Normal Range
Maximum range
Normal Range
AM2311A User Guide
-40 -20 0 20 40 60 80 100
1.1 Working conditions
1.2 RH accuracy at different temperatures
The sensor performance is stable in the suggested
working scope, as shown in Figure 4.Long-term
exposure to abnormal scope,especially when
humidity > 80%,may lead to temporary signal drift
(drift + 3% RH after 60 hours).When the sensor is
restored to normal working conditions,it will slowly
restore itself to the correct state.Refer to Recovery
Processing in Section 2.2 to speed up the recovery
process.Long-term use under abnormal conditions
will accelerate the aging of products.
2.1 Storage conditions and instructions
2 Application information
The humidity sensitivity level (MSL) is 1, according to
IPC/JEDEC J-STD-020 standard. Therefore, it is
recommended to use it within one year after delivery.
Humidity sensor is not an ordinary electronic
component, and it needs careful protection, which
users must pay attention to. Long-term exposure to
high concentration of chemical vapor will cause the
sensor reading to drift.Therefore, it is recommended
that the sensor be stored in the original package
including sealed ESD bag, and meet the following
conditions: temperature range 10℃ - 50℃(0 - 85℃
in a limited time), humidity 20 - 60% RH (no ESD
packaged sensor). For sensors that have been
removed from the original package, we recommend
that they be stored in antistatic bags made of metal
PET / AL / CPE.
During production and transportation, sensors should
avoid exposure to high concentration of chemical
solvents and prolonged exposure. Avoid exposure to
volatile glue, adhesive tape, stickers or volatile
packaging materials, such as foamed foil, foam
material, etc. The production area should be well
ventilated.
2.2 Recovery processing
As mentioned above, if the sensor is exposed to
extreme working conditions or chemical vapor, the
reading will drift. It can be restored to the calibration
state by processing as follows.
Drying: Keep for 10 hours at 80 - 85℃ and less than
5% RH humidity.
9
Rehydration: Keep for 12 hours at 20 - 30℃ with the
humidity of more than 75 % RH.
2.3 Temperature influence
The relative humidity of gases depends largely
on temperature. Therefore, when measuring
humidity, all sensors measuring the same humidity
should work at the same temperature as possible.
When testing, it is necessary to ensure that the
tested sensors and reference sensors are at the
same temperature, and then compare the humidity
readings.
Moreover, when the measurement frequency is too
high, the temperature of the sensor itself will rise,
which will affect the measurement accuracy. In order
to make its temperature rise below 0.1℃ , the
activation time of AM2311A should not exceed 10% of
the measurement time - it is recommended to measure
data every 2 seconds.
9 75%RH can be easily generated from saturated NaCl.
Temperature (℃)
Figure Typical5 humidity error between 0~80 °C, unit: (% RH)
Relative Humidity (%RH)
Note: Above errors are the tested typical errors (excluding
hysteresis) with the high precision dew-point instrument as
reference instrument.
The RH accuracy at 25℃ is defined in Figure. 2, and
the typical humidity error at other temperatures
is shown in Fig. 5.
0 5 10 1 5 2 0 2 5 3 0 3 5 40 4 5 5 0 55 6 0 6 5 7 0 7 5 8 0
100
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2 0
3 0
4 0
5 0
6 0
7 0
8 0
9 0
±3 ±4 ±5 ±6
±8±6±5
±5
±4
±5±6
±7
±5 ±4
±6
±5
±4
±5
±5
±7