SHT21 SENSIRION, SHT21 Datasheet - Page 10

• 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

Datasheet SHT21
In the example given in Figure 15 and Figure 16 the
relative humidity results to be 42.5%RH.
The physical value RH given above corresponds to the
relative humidity above liquid water according to World
Meteorological Organization (WMO). For relative humidity
above ice RH
relative humidity above water RH
equation is given in the following, compare also
Application Note “Introduction to Humidity:
Units are %RH for relative humidity and °C for
temperature. The corresponding coefficients are defined
as follows: β
272.62°C.
6.2
The temperature T is calculated by inserting temperature
signal output S
matter which resolution is chosen:
7 Environmental Stability
The SHT2x sensor series were tested according to AEC-
Q100 Rev. G qualification test method. Sensor
specifications are tested to prevail under the AEC-Q100
temperature grade 2 test conditions listed in Table 9
Table 9: Performed qualification test series. HTOL = High
Temperature Operating Lifetime, TC = Temperature Cycles,
UHST = Unbiased Highly accelerated Stress Test, THB =
Temperature Humidity Biased. For details on ESD see Sect. 4.1.
16
17
www.sensirion.com
T
RH
RH
Environment Standard
HTOL
TC
UHST
THB
ESD immunity HBM 4kV, MM 200V, CDM
Latch-up
Temperature range is -40 to 105°C (AEC-Q100 temperature grade 2).
According to accuracy and long term drift specification given on Page 2.

i




RH
Temperature Conversion
46.85
6
w


125
exp
w

i
125°C, 408 hours
-50°C - 125°C, 1000 cycles
130°C / 85%RH / ≈2.3bar, 96h Within
85°C / 85%RH, 1000h
750V/500V (corner/other pins)
force current of ±100mA with
T
T
= 17.62, λ
the values need to be transformed from
175.72
amb
into the following formula (result in °C), no

 


λ
β
= 125°C
S
2
w
w
RH
16


t
t


 

2
S
w
16
T
= 243.12°C, β
exp

 

λ
w
β
i
i
at temperature t. The


t
t

 

i
Results
Within
specifications
Within
specifications
specifications
Within
specifications
Qualified
Qualified
= 22.46, λ
Version 1.1 – May 2010
17
16
.
i
=
Sensor performance under other test conditions cannot be
guaranteed and is not part of the sensor specifications.
Especially, no guarantee can be given for sensor
performance in the field or for customer’s specific
application.
If sensors are qualified for reliability and behavior in
extreme conditions, please make sure that they
experience same conditions as the reference sensor. It
should be taken into account that response times in
assemblies may be longer, hence enough dwell time for
the measurement shall be granted. For detailed
information please consult Application Note “Testing
Guide”.
8 Packaging
8.1
SHT2x sensors are provided in DFN packaging (in
analogy with QFN packaging). DFN stands for Dual Flat
No leads.
The sensor chip is mounted to a lead frame made of Cu
and plated with Ni/Pd/Au. Chip and lead frame are over
molded by green epoxy-based mold compound. Please
note that side walls of sensors are diced and hence lead
frame at diced edge is not covered with respective
protective coating. The total weight of the sensor is 25mg.
8.2
For SHT2x a filter cap SF2 will be provided. It is designed
for fast response times and compact size. Please find the
datasheet on Sensirion’s web page.
For testing of SHT2x sensors sockets, such as from
Plastronics,
recommended (see e.g. www.locknest.com).
8.3
All SHT2x are laser marked with an alphanumeric, five-
digit code on the sensor – see Figure 19.
The marking on the sensor consists of two lines with five
digits each. The first line denotes the sensor type
(SHT21). The first digit of the second line defines the
output mode (D = digital, Sensibus and I
SDM). The second digit defines the manufacturing year (0
= 2010, 1 = 2011, etc.). The last three digits represent an
alphanumeric tracking code. That code can be decoded by
Sensirion only and allows for tracking on batch level
through production, calibration and testing – and will be
provided upon justified request.
Packaging Type
Filter Cap and Sockets
Traceability Information
part
number
10LQ50S13030
2
C, P = PWM, S =
10/12
are