SHT21 SENSIRION, SHT21 Datasheet - Page 2

• Manufacturer Part Number: SHT21
• Description: Humidity/Temperture Sensor
• Manufacturer: SENSIRION

Specifications of SHT21

• Operating Temperature Range: -40°C To +125°C
• No. Of Pins: 6
• Supply Voltage: 3V
• Humidity Sensor Type: Capacitive
• Sensor Case Style: DFN
• Humidity Range: 0% To 100%
• Response Time: 8s
• Accuracy: ± 2%
• Supply Current: 300µA

± 10
 RH (%RH)
Sensor Performance
Relative Humidity
Parameter
Resolution
Accuracy
tolerance
Repeatability
Hysteresis
Nonlinearity
Response time
Operating Range extended
Long Term Drift
± 8
± 6
± 4
± 2
± 0
Figure 2 Typical and maximal tolerance at 25°C for relative
humidity. For extensive information see Users Guide, Sect. 1.2.
Electrical Specification
Parameter
Supply Voltage, VDD
Supply Current, IDD
Power Dissipation
Heater
Communication
Table 1
values see Section 4.1 of Users Guide.
1
be reduced to 12/8bit, 11/11bit or 13/10bit by command to user register.
2
Values exclude hysteresis and long term drift and are applicable to non-
condensing environments only.
3
4
reversible offset with slow kinetics (<3%RH after 200hours at 90%RH). For more
details please see Section 1.1 of the Users Guide.
www.sensirion.com
Default measurement resolution is 14bit (temperature) / 12bit (humidity). It can
Time for achieving 63% of a step function, valid at 25°C and 1m/s airflow.
Accuracies are tested at Outgoing Quality Control at 25°C (77°F) and 3.0V.
Normal operating range: 0-80%RH, beyond this limit sensor may read a
0
10
2
1
Electrical specification. For absolute maximum
20
3
5
6
Condition
1234
6
30
normal
 63%
12 bit
sleep mode
measuring
sleep mode
measuring
average 8bit
VDD = 3.0 V
digital 2-wire interface, true I
8 bit
max
Conditions min
typ
40
4
50
min
0
5.5mW, T = + 0.5-1.5°C
270
2.1
0.8
see Figure 2
-
-
-
60
Relative Humidity (%RH)
< 0.5
2.0
0.1
0.04
<0.1
typ
0.7
1
8
0.15
300
3.0
0.5
0.9
3.2
typ
70
maximal tolerance
typical tolerance
max
100
80
max Units
330
3.6
0.4
1.2
1.0
2
C protocol
-
%RH/yr
90
Units
%RH
%RH
%RH
%RH
%RH
%RH
%RH
%RH
Version 1.1 – May 2010
mW
µW
µW
µA
µA
s
V
100
± 3.0
± 2.5
± 2.0
± 1.5
± 1.0
± 0.5
± 0.0
Temperature
Parameter
Resolution
Accuracy
tolerance
Repeatability
Operating Range extended
Response Time
Long Term Drift
Figure 3 Maximal tolerance for temperature sensor in °C.
Packaging Information
Sensor Type
SHT21
This datasheet is subject to change and may be amended
without prior notice.
5
tapes, adhesives, packaging materials, etc. For more details please refer to
Handling Instructions.
6
fixed VDD = 3.0V and T<60°C. The average value is based on one 8bit
measurement per second.
7
T (°C)
Response time depends on heat conductivity of sensor substrate.
Min and max values of Supply Current and Power Dissipation are based on
Value may be higher in environments with vaporized solvents, out-gassing
-40
2
1
-20
567
7
Tape & Reel
Tape & Reel
Tape & Reel
Packaging
Condition
0
 63%
14 bit
12 bit
max
typ
20
4
Quantity
min
40
-40
-40
5
maximal tolerance
typical tolerance
1500
5000
400
see Figure 3
< 0.04
60
0.3
0.1
0.01
0.04
typ
Order Number
Temperature (°C)
1-100707-01
1-100645-01
1-100694-01
80
max
125
257
30
100
Units
°C/yr
°C
°C
°C
°C
°C
°C
°F
s
2/12
120