www.sensirion.com Version 4 – May 2014 1/10
Datasheet SHT21P
Humidity and Temperature Sensor IC
Fully calibrated
Analog output, PWM interface
Low power consumption
Excellent long term stability
DFN type package – reflow solderable
Dimensions
Figure 1: Drawing of SHT21P sensor package, dimensions
are given in mm (1mm = 0.039inch), tolerances are ±0.1mm.
The die pad (center pad) is internally connected to VSS. The NC
pads must be left floating. Numbering of E/O pads starts at lower
right corner (indicated by notch in die pad) and goes clockwise
(compare Table 2).
Sensor Chip
SHT21P features a generation 4C CMOSens® chip.
Besides the capacitive relative humidity sensor and the
band gap temperature sensor, the chip contains an
amplifier, A/D converter, OTP memory and a digital
processing unit.
Material Contents
While the sensor itself is made of Silicon the sensors’
housing consists of a plated Cu lead-frame and green
epoxy-based mold compound. The device is free of Pb, Cd
and Hg – hence it is fully RoHS and WEEE compliant.
Additional Information
Additional information such as Application Notes is
available from the web page www.sensirion.com/sht21.
For more information please contact Sensirion via
info@sensirion.com.
1.0
1.0
2.4
0.3
0.4
1.5
0.4
0.75
1.1
0.2
SCL
SDA
NC
NC
VSS
VDD
Bottom
View
SHT21
P0AC4
3.0
2.2
1.4 max
3.0
0.3 typ
2.4 max
Product Summary
The SHT21 humidity and temperature sensor of Sensirion
has become an industry standard in terms of form factor
and intelligence: Embedded in a reflow solderable Dual
Flat No leads (DFN) package of 3 x 3mm foot print and
1.1mm height it provides calibrated, linearized sensor
signals in analog Pulse Width Modulated (PWM) format.
The SHT2x sensors contain a capacitive type humidity
sensor, a band gap temperature sensor and specialized
analog and digital integrated circuit – all on a single
CMOSens® chip. This yields in an unmatched sensor
performance in terms of accuracy and stability as well as
minimal power consumption.
PWM signal runs on a base frequency of 120Hz, the data
signal is provided on SDA line. Pulling SCL high or low
allows for switching between humidity and temperature,
respectively. The sensor measures twice per second. The
PWM signal may be converted to an analog ratiometric
interface by adding a low pass filter.
Every sensor is individually calibrated and tested. Lot
identification is printed on the sensor.
With this set of features and the proven reliability and
long-term stability, the SHT2x sensors offer an
outstanding performance-to-price ratio. For testing SHT2x
two evaluation kits EK-H4 and EK-H5 are available.
www.sensirion.com Version 4 – May 2014 2/10
Sensor Performance
Relative Humidity
123
Parameter
Condition
Value
Units
Resolution
12 bit
0.04
%RH
Accuracy
tolerance 1
typ
2.0
%RH
max
see Figure 2
%RH
Repeatability
0.1
%RH
Hysteresis
1
%RH
Nonlinearity
<0.1
%RH
Response time 2
63%
8
s
Operating Range
extended 3
0 to 100
%RH
Long Term Drift 4
Typ.
< 0.25
%RH/yr
± 0
± 2
± 4
± 6
± 8
± 10
010 20 30 40 50 60 70 80 90 100
Relative Humidity (%RH)
DRH (%RH)
maximum accuracy
typical accuracy
Figure 2 Typical and maximal tolerance at 25°C for relative
humidity. For extensive information see Users Guide, Sect. 1.2.
Electrical Specification
Parameter
Condition
min
typ
max
Units
Supply Voltage, VDD
2.1
3.0
3.6
V
Supply Current, IDD 5
180
µA
Power Dissipation 5
0.54
mW
PWM frequency
40 °C
108
120
132
Hz
Temperature drift of
PWM frequency
-0.07
-0.12
Hz/°C
Measurement
Frequency
2
Hz
Switch RH/T on SDA
SCL up RH; SCL down T
Table 1 Electrical specification. For absolute maximum
values see Chapter 4.1 of Users Guide.
1
Accuracies are tested at Outgoing Quality Control at 25°C and 3.0V. Values
exclude hysteresis and long term drift and are applicable to non-condensing
environments only.
2
Time for achieving 63% of a step function, valid at 25°C and 1 m/s airflow.
3
Normal operating range: 0-80%RH, beyond this limit sensor may read a
reversible offset with slow kinetics (+3%RH after 60h at humidity >80%RH). For
more details please see Section 1.1 of the Users Guide.
Temperature
456
Parameter
Condition
Value
Units
Resolution
14 bit
0.01
°C
Accuracy
tolerance 1
typ
0.3
°C
max
see Figure 3
°C
Repeatability
0.1
°C
Operating Range
extended 3
-40 to 125
°C
Response Time 6
63%
5 to 30
s
Long Term Drift7
Typ.
< 0.02
°C/yr
± 0.0
± 0.5
± 1.0
± 1.5
± 2.0
-40 -20 020 40 60 80 100 120
Temperature (°C)
DT (°C)
maximum accuracy
typical accuracy
Figure 3 Typical and maximal temperature accuracy tolerance
Packaging Information
Sensor Type
Packaging
Quantity
Order Number
SHT21P
Tape & Reel
400
1-100711-01
Tape & Reel
1500
1-100700-01
Tape & Reel
5000
1-100699-01
This datasheet is subject to change and may be amended
without prior notice.
4
4
Typical value for operation in normal RH/T operating range. Max. value is <
0.5 %RH/y. Value may be higher in environments with vaporized solvents, out-
gassing tapes, adhesives, packaging materials, etc. For more details please
refer to Handling Instructions.
5
Values of Supply Current and Power Dissipation are based upon fixed VDD =
3.0V and T = 25°C.
6
Response time depends on heat conductivity of sensor substrate.
7
Max. value is < 0.04°C/y.
www.sensirion.com Version 4 – May 2014 3/10
Users Guide SHT21P
1 Extended Specifications
For details on how Sensirion is specifying and testing
accuracy performance please consult Application Note
“Statement on Sensor Specification”.
1.1 Operating Range
The sensor works stable within recommended Normal
Range – see Figure 4. Long term exposure to conditions
outside Normal Range, especially at humidity >80%RH,
may temporarily offset the RH signal (+3%RH after 60h).
After return into the Normal Range it will slowly return
towards calibration state by itself. Prolonged exposure to
extreme conditions may accelerate ageing.
Figure 4 Operating Conditions
1.2 RH accuracy at various temperatures
Typical RH accuracy at 25°C is defined in Figure 2. For
other temperatures, typical accuracy has been evaluated
to be as displayed in Figure 5.
100 ±3.5 ±3 ±3 ±3 ±3 ±3 ±3.5 ±4 ±4
90 ±3.5 ±3 ±2.5 ±2.5 ±2.5 ±2.5 ±3 ±3.5 ±4
80 ±3 ±2.5 ±2 ±2 ±2 ±2.5 ±2.5 ±3 ±3.5
70 ±3 ±2.5 ±2 ±2 ±2 ±2 ±2.5 ±2.5 ±3
60 ±2.5 ±2 ±2 ±2 ±2 ±2 ±2 ±2.5 ±2.5
50 ±2.5 ±2 ±2 ±2 ±2 ±2 ±2 ±2 ±2.5
40 ±2.5 ±2 ±2 ±2 ±2 ±2 ±2 ±2 ±2
30 ±2.5 ±2 ±2 ±2 ±2 ±2 ±2 ±2 ±2
20 ±2.5 ±2.5 ±2 ±2 ±2 ±2 ±2 ±2 ±2
10 ±3 ±3 ±2.5 ±2.5 ±2.5 ±2.5 ±2.5 ±2.5 ±2.5
0 ±3.5 ±3.5 ±3 ±3 ±3 ±3 ±3 ±3 ±3
010 20 30 40 50 60 70 80
Relative Humidity [%RH]
Temperature [°C]
Figure 5 Typical accuracy of relative humidity measurements
given in %RH for temperatures 0 – 80°C.
2 Application Information
2.1 Soldering Instructions
The DFN’s die pad (centre pad) and perimeter I/O pads
are fabricated from a planar copper lead-frame by over-
molding leaving the die pad and I/O pads exposed for
mechanical and electrical connection. Both the I/O pads
and die pad should be soldered to the PCB. In order to
prevent oxidation and optimize soldering, the bottom side
of the sensor pads is plated with Ni/Pd/Au.
On the PCB the I/O lands
8
should be 0.2mm longer than
the package I/O pads. Inward corners may be rounded to
match the I/O pad shape. The I/O land width should match
the DFN-package I/O-pads width 1:1 and the land for the
die pad should match 1:1 with the DFN package – see
Figure 6.
The solder mask
9
design for the land pattern preferably is
of type Non-Solder Mask Defined (NSMD) with solder
mask openings larger than metal pads. For NSMD pads,
the solder mask opening should be about 120μm to
150μm larger than the pad size, providing a 60μm to 75μm
design clearance between the copper pad and solder
mask. Rounded portions of package pads should have a
matching rounded solder mask-opening shape to minimize
the risk of solder bridging. For the actual pad dimensions,
each pad on the PCB should have its own solder mask
opening with a web of solder mask between adjacent
pads.
Figure 6 Recommended metal land pattern for SHT2x. Values
in mm. Die pad (centre pad) may be left floating or be connected
to ground, NC pads shall be left floating. The outer dotted line
represents the outer dimension of the DFN package.
For solder paste printing a laser-cut, stainless steel stencil
with electro-polished trapezoidal walls and with 0.125mm
stencil thickness is recommended. For the I/O pads the
8
The land pattern is understood to be the metal layer on the PCB, onto which
the DFN pads are soldered to.
9
The solder mask is understood to be the insulating layer on top of the PCB
covering the connecting lines.
0
20
40
60
80
100
-40 -20 0 20 40 60 80 100 120
Temperature (°C)
Relative Humidity (%)
Max.
Range
Normal
Range
1.0
1.0
0.3
0.4
1.5
0.4
0.7
0.2
0.2
2.4
Datasheet SHT21P
www.sensirion.com Version 4 – May 2014 4/10
stencil apertures should be 0.1mm longer than PCB pads
and positioned with 0.1mm offset away from the centre of
the package. The die pad aperture should cover about 70
– 90% of the pad area – say up to 1.4mm x 2.3mm
centered on the thermal land area. It can also be split in
two openings.
Due to the low mounted height of the DFN, “no clean”
type 3 solder paste
10
is recommended as well as Nitrogen
purge during reflow.
Figure 7 Soldering profile according to JEDEC standard. TP <=
260°C and tP < 30sec for Pb-free assembly. TL < 220°C and tL <
150sec. Ramp-up/down speeds shall be < 5°C/sec.
It is important to note that the diced edge or side faces of
the I/O pads may oxidise over time, therefore a solder fillet
may or may not form. Hence there is no guarantee for
solder joint fillet heights of any kind.
For soldering SHT2x, standard reflow soldering ovens may
be used. The sensor is qualified to withstand soldering
profile according to IPC/JEDEC J-STD-020 with peak
temperatures at 260°C during up to 30sec for Pb-free
assembly in IR/Convection reflow ovens (see Figure 7).
For manual soldering contact time must be limited to 5
seconds at up to 350°C.
Immediately after the exposure to high temperatures the
sensor may temporarily read a negative humidity offset
(typ. -1 to -2 %RH after reflow soldering). This offset
slowly disappears again by itself when the sensor is
exposed to ambient conditions (typ. within 1-3 days). If RH
testing is performed immediately after reflow soldering,
this offset should be considered when defining the test
limits.
In no case, neither after manual nor reflow soldering, a
board wash shall be applied. Therefore, and as mentioned
above, it is strongly recommended to use “no-clean” solder
paste. In case of applications with exposure of the sensor
to corrosive gases or condensed water (i.e. environments
with high relative humidity) the soldering pads shall be
sealed (e.g. conformal coating) to prevent loose contacts
or short cuts.
10
Solder types are related to the solder particle size in the paste: Type 3 covers
the size range of 25 – 45 µm (powder type 42).
2.2 Storage Conditions and Handling Instructions
Moisture Sensitivity Level (MSL) is 1, according to
IPC/JEDEC J-STD-020. At the same time, it is
recommended to further process the sensors within 1 year
after date of delivery.
It is of great importance to understand that a humidity
sensor is not a normal electronic component and needs to
be handled with care. Chemical vapors at high
concentration in combination with long exposure times
may offset the sensor reading.
For this reason it is recommended to store the sensors in
original packaging including the sealed ESD bag at
following conditions: Temperature shall be in the range of
10°C – 50°C and humidity at 20 – 60%RH (sensors that
are not stored in ESD bags). For sensors that have been
removed from the original packaging we recommend to
store them in ESD bags made of metal-in PE-HD
11
.
In manufacturing and transport the sensors shall be
prevented of high concentration of chemical solvents and
long exposure times. Out-gassing of glues, adhesive tapes
and stickers or out-gassing packaging material such as
bubble foils, foams, etc. shall be avoided. Manufacturing
area shall be well ventilated.
For more detailed information please consult the
document “Handling Instructions” or contact Sensirion.
2.3 Temperature Effects
Relative humidity reading strongly depends on
temperature. Therefore, it is essential to keep humidity
sensors at the same temperature as the air of which the
relative humidity is to be measured. In case of testing or
qualification the reference sensor and test sensor must
show equal temperature to allow for comparing humidity
readings.
If the sensor shares a PCB with electronic components
that produce heat it should be mounted in a way that
prevents heat transfer or keeps it as low as possible.
Measures to reduce heat transfer can be ventilation,
reduction of copper layers between the sensor and the
rest of the PCB or milling a slit into the PCB around the
sensor – see Figure 8.
11
For example, 3M antistatic bag, product “1910” with zipper.
Temperature
Time
tP
TP
TL
TS (max)
tL
preheating
critical zone
Datasheet SHT21P
www.sensirion.com Version 4 – May 2014 5/10
Figure 8 Top view of example of mounted SHT2x with slits
milled into PCB to minimize heat transfer.
2.4 Light
The SHT2x is not light sensitive. Prolonged direct
exposure to sunshine or strong UV radiation may age the
sensor.
2.5 Materials Used for Sealing / Mounting
Many materials absorb humidity and will act as a buffer
increasing response times and hysteresis. Materials in the
vicinity of the sensor must therefore be carefully chosen.
Recommended materials are: Any metals, LCP, POM
(Delrin), PTFE (Teflon), PEEK, PP, PB, PPS, PSU, PVDF,
PVF.
For sealing and gluing (use sparingly): Use high filled
epoxy for electronic packaging (e.g. glob top, underfill),
and Silicone. Out-gassing of these materials may also
contaminate the sensor (see Section 2.2). Therefore try to
add the sensor as a last manufacturing step to the
assembly, store the assembly well ventilated after
manufacturing or bake at >50°C for 24h to outgas
contaminants before packing.
Interface Specifications
Pin
Name
Comment
1
SDA
Data bit-stream
2
VSS
Ground
5
VDD
Supply Voltage
6
SCL
Selector for RH or T
3,4
NC
Not connected
Table 2 SHT21P pin assignment (top view)
2.6 Power Pins (VDD, VSS)
The supply voltage of SHT21P must be in the range of 2.1
– 3.6V, recommended supply voltage is 3.0V. Power
supply pins Supply Voltage (VDD) and Ground (VSS) must
be decoupled with a 100nF capacitor, that shall be placed
as close to the sensor as possible – see Figure 9.
2.7 SCL – Output Selector Pad
SCL is used to select humidity or temperature output. SCL
high yields humidity output, SCL low yields temperature
output. Please note that a change of SCL will affect the
output on SDA after maximal 1.2 seconds.
Figure 9 Typical application circuit, including decoupling of
VDD and VSS by a capacitor.
2.8 SDA – Bit Stream Pad
On SDA the sensor is providing PWM output. The signal is
carrying humidity or temperature data depending on SCL
being high or low, respectively. See Table 4 for detailed
I/O characteristic of the sensor.
3 Electrical Characteristics
3.1 Absolute Maximum Ratings
The electrical characteristics of SHT21P are defined in
Table 1. The absolute maximum ratings as given in Table
3 are stress ratings only and give additional information.
Functional operation of the device at these conditions is
not implied. Exposure to absolute maximum rating
conditions for extended periods may affect the sensor
reliability (e.g. hot carrier degradation, oxide breakdown).
SDA
SCL
VSS
VDD
C = 100nF
SHT2x
PWM bit stream
Select RH or T
1
6
5
2
4
3
Datasheet SHT21P
www.sensirion.com Version 4 – May 2014 6/10
Parameter
min
max
Units
VDD to VSS
-0.3
5
V
Digital IO Pins (SDA, SCL)
to VSS
-0.3
VDD + 0.3
V
Input Current on any Pin
-100
100
mA
Table 3 Electrical absolute maximum ratings
ESD immunity is qualified according to JEDEC JESD22-
A114 method (Human Body Model at 4kV), JEDEC
JESD22-A115 method (Machine Model 200V) and ESDA
ESD-STM5.3.1-1999 and AEC-Q100-011 (Charged
Device Model, 750V corner pins, 500V other pins). Latch-
up immunity is provided at a force current of 100mA with
Tamb = 125°C according to JEDEC JESD78. For exposure
beyond named limits the sensor needs additional
protection circuit.
3.2 Input / Output Characteristics
The electrical characteristics such as power consumption,
low and high level input and output voltages depend on
the supply voltage. For proper communication with the
sensor it is essential to make sure that signal design is
strictly within the limits given in Table 4.
Parameter
min
typ
max
Units
Output Low Voltage, VOL
0
V
Output High Voltage, VOH
VDD
V
Output Sink Current, IOL
40
µA
Table 4 DC characteristics of output pad. VDD = 2.1 V to 3.6 V,
T = -40 °C to 125 °C, unless otherwise noted.
4 Communication with Sensor
4.1 Start up Sensor
As a first step, the sensor is powered up to VDD (between
2.1V and 3.6V). After power-up, the sensor needs at most
150ms for reaching idle state. During that time SDA is in
undefined state. Then the sensor starts measuring and
providing data on PWM bit-stream.
4.2 PWM Specification
Pulse Width Modulation runs on a constant frequency and
the measured information is provided as duty cycle on that
frequency – see Figure 10. Such information is measured
humidity for SCL pulled high and temperature for SCL
pulled low.
Figure 10 PWM signal. Base frequency runs constantly at
approximately 120 Hz, hence tF is about 8.3ms. The signal is
provided on tPW as a ratio of tF.
The measured data – either humidity or temperature – is
provided as ratio of tPW and tF. tPW shall always be given as
ratio of tF to make it independent of variations of the base
frequency.
5 Conversion of Signal Output
Resolution is set to 10 bit relative humidity and 12 bit
temperature reading and cannot be changed. The sensor
reading is linear and hence it can be converted to a
physical value by an easy linear equation.
5.1 Relative Humidity Conversion
With the relative humidity signal output the relative
humidity RH is obtained by the following formula (result in
%RH):
F
PW
t
t
1256RH
The physical value RH given above corresponds to
the relative humidity above liquid water according to
World Meteorological Organization (WMO). For
relative humidity values above ice RHi the values need to
be transformed as from relative humidity above water RHw
at a certain temperature t follows – compare also
Application Note “Introduction to Humidity”:
tλ
tβ
exp
tλ
tβ
expRHRH
i
i
w
w
wi
Units are %RH for relative humidity and °C for
temperature. The corresponding coefficients are defined
as follows: βw = 17.62, λw = 243.12°C, βi = 22.46, λi =
272.62°C.
5.2 Temperature Conversion
The temperature T is calculated by inserting the ratio of
tPW and tF into the following formula (result in °C):
F
PW
t
t
175.7246.85T
SDA
VDD
0V
tF
tPW
Datasheet SHT21P
www.sensirion.com Version 4 – May 2014 7/10
6 Environmental Stability
The SHT2x sensor series were tested based on AEC-
Q100 Rev. G qualification test method where applicable.
Sensor specifications are tested to prevail under the AEC-
Q100 temperature grade 1 test conditions listed in Table
5
13
. 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.
Environment
Standard
Results17
HTOL
125°C, 408 hours
Pass
TC
-50°C - 125°C, 1000 cycles
Pass
UHST
130°C / 85%RH / ≈2.3bar, 96h
Pass
THB
85°C / 85%RH, 1000h
Pass
HTSL
150°C, 1000h
Pass
ELFR
125°C, 48h
Pass
ESD immunity
HBM 4kV, MM 200V, CDM
750V/500V (corner/other pins)
Pass
Latch-up
force current of ±100mA with Tamb
= 125°C
Pass
Table 5: Qualification tests: HTOL = High Temperature
Operating Lifetime, TC = Temperature Cycles, UHST =
Unbiased Highly accelerated Stress Test, THB = Temperature
Humidity Biased, HTSL = High Temperature Storage Lifetime,
ELFR = Early Life Failure Rate. For details on ESD see Sect.
4.1.
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 “Qualification
Guide”.
7 Packaging
7.1 Packaging Type
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
13
Sensor operation temperature range is -40 to 125°C (AEC-Q100 temperature
grade 1).
17
According to accuracy and long term drift specification given on Page 2.
frame at diced edge is not covered with respective
protective coating. The total weight of the sensor is 25mg.
7.2 Filter Cap and Sockets
For SHT2x a filter cap SF2 is available. 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, part number 10LQ50S13030 are
recommended (see e.g. www.locknest.com).
7.3 Traceability Information
All SHT21 are laser marked with an alphanumeric, five-
digit code on the sensor – see Figure 11.
Figure 11 Laser marking on sensor. For details see text.
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 I2C, P = PWM, S =
SDM). The second digit defines the manufacturing year (0
= 2010, 1 = 2011, etc.). The last three digits eventually
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.
Reels are also labeled, as displayed in Figure 12 and
Figure 13, and give additional traceability information.
Figure 12: First label on reel: XX = Sensor Type (21 for SHT21),
O = Output mode (D = Digital, P = PWM, S = SDM), NN =
product revision no., Y = last digit of year, RRR = number of
sensors on reel divided by 10 (200 for 2000 units), TTTTT =
Traceability Code.
SHT21
P0AC4
Lot No.: XXO-NN-YRRRTTTTT
Quantity: RRRR
RoHS: Compliant
Lot No.
Datasheet SHT21P
www.sensirion.com Version 4 – May 2014 8/10
Figure 13: Second label on reel: For Device Type and Part
Order Number (See Packaging Information on page 2), Delivery
Date (also Date Code) is date of packaging of sensors (DD =
day, MM = month, YYYY = year), CCCC = Sensirion order
number.
7.4 Shipping Package
SHT2x are provided in tape & reel shipment packaging,
sealed into antistatic ESD bags. For SHT21P standard
packaging sizes are 400, 1500 and 5000 units per reel.
Each reel contains 440mm (55 pockets) header tape and
200mm (25 pockets) trailer tape.
The drawing of the packaging tapes with sensor
orientation is shown in Figure 13. The reels are provided in
sealed antistatic bags.
Figure 14 Sketch of packaging tape and sensor orientation.
Header tape is to the right and trailer tape to the left on this
sketch.
8.0
2.0
4.0
0.3
1.3
R0.3 MAX
R0.25
Ø1.5 MIN
Ø1.5 MIN
3.3
0.25
3.3
1.75
5.5
12.0
Device Type: 1-100PPP-NN
Description: Humidity & Temperature Sensor
SHTxx
Part Order No. 1-100PPP-NN or Customer Number
Date of Delivery: DD.MM.YYYY
Order Code: 46CCCC / 0
Datasheet SHT21P
www.sensirion.com Version 4 – May 2014 9/10
Revision History
Date
Version
Page(s)
Changes
19 Aug 2009
0.6
1, 6
Figure 1 adapted, add details to Section 1.2, 5.1 and Chapter 7
29 Jan 2010
1.0
1 – 9
Completely revised version. Require Change Protocol for details.
5 May 2010
1.1
1 – 9
Elimination of errors and addition of information (ask for change protocol)
31 May 2011
2
1 – 4,
6 – 10
Updated temperature accuracy specifications, MSL and standards. Elimination of
errors. For detailed information, please require complete change list at
info@sensirion.com.
December 2011
3
1, 7
Minor text adaptations and corrections.
May 2014
4
1-4, 7-8
Sensor window dimension updated, several minor adjustments
Datasheet SHT21P
www.sensirion.com Version 4 – May 2014 10/10
Important Notices
Warning, Personal Injury
Do not use this product as safety or emergency stop devices or in
any other application where failure of the product could result in
personal injury. Do not use this product for applications other
than its intended and authorized use. Before installing, handling,
using or servicing this product, please consult the data sheet and
application notes. Failure to comply with these instructions could
result in death or serious injury.
If the Buyer shall purchase or use SENSIRION products for any
unintended or unauthorized application, Buyer shall defend, indemnify
and hold harmless SENSIRION and its officers, employees,
subsidiaries, affiliates and distributors against all claims, costs,
damages and expenses, and reasonable attorney fees arising out of,
directly or indirectly, any claim of personal injury or death associated
with such unintended or unauthorized use, even if SENSIRION shall be
allegedly negligent with respect to the design or the manufacture of the
product.
ESD Precautions
The inherent design of this component causes it to be sensitive to
electrostatic discharge (ESD). To prevent ESD-induced damage and/or
degradation, take customary and statutory ESD precautions when
handling this product.
See application note “ESD, Latchup and EMC” for more information.
Warranty
SENSIRION warrants solely to the original purchaser of this product for
a period of 12 months (one year) from the date of delivery that this
product shall be of the quality, material and workmanship defined in
SENSIRION’s published specifications of the product. Within such
period, if proven to be defective, SENSIRION shall repair and/or
replace this product, in SENSIRION’s discretion, free of charge to the
Buyer, provided that:
notice in writing describing the defects shall be given to
SENSIRION within fourteen (14) days after their appearance;
such defects shall be found, to SENSIRION’s reasonable
satisfaction, to have arisen from SENSIRION’s faulty design,
material, or workmanship;
the defective product shall be returned to SENSIRION’s factory at
the Buyer’s expense; and
the warranty period for any repaired or replaced product shall be
limited to the unexpired portion of the original period.
This warranty does not apply to any equipment which has not been
installed and used within the specifications recommended by
SENSIRION for the intended and proper use of the equipment.
EXCEPT FOR THE WARRANTIES EXPRESSLY SET FORTH
HEREIN, SENSIRION MAKES NO WARRANTIES, EITHER EXPRESS
OR IMPLIED, WITH RESPECT TO THE PRODUCT. ANY AND ALL
WARRANTIES, INCLUDING WITHOUT LIMITATION, WARRANTIES
OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR
PURPOSE, ARE EXPRESSLY EXCLUDED AND DECLINED.
SENSIRION is only liable for defects of this product arising under the
conditions of operation provided for in the data sheet and proper use of
the goods. SENSIRION explicitly disclaims all warranties, express or
implied, for any period during which the goods are operated or stored
not in accordance with the technical specifications.
SENSIRION does not assume any liability arising out of any application
or use of any product or circuit and specifically disclaims any and all
liability, including without limitation consequential or incidental
damages. All operating parameters, including without limitation
recommended parameters, must be validated for each customer’s
applications by customer’s technical experts. Recommended
parameters can and do vary in different applications.
SENSIRION reserves the right, without further notice, (i) to change the
product specifications and/or the information in this document and (ii) to
improve reliability, functions and design of this product.
© Copyright 2014 by Sensirion.
CMOSens® is a trademark of Sensirion
All rights reserved
Headquarters and Subsidiaries
SENSIRION AG
Laubisruetistr. 50
CH-8712 Staefa ZH
Switzerland
phone: +41 44 306 40 00
fax: +41 44 306 40 30
info@sensirion.com
www.sensirion.com
Sensirion Inc., USA
phone: +1 805 409 4900
info_us@sensirion.com
www.sensirion.com
Sensirion Japan Co. Ltd.
phone: +81 3 3444 4940
info@sensirion.co.jp
www.sensirion.co.jp
Sensirion Korea Co. Ltd.
phone: +82 31 337 7700~3
info@sensirion.co.kr
www.sensirion.co.kr
Sensirion China Co. Ltd.
phone: +86 755 8252 1501
info@sensirion.com.cn
www.sensirion.com.cn
Sensirion AG (Germany)
phone: +41 44 927 11 66
info@sensirion.com
www.sensirion.com
To find your local representative, please visit www.sensirion.com/contact
