SHT4xA
4th Generation, High-Accuracy, 16-bit, Automotive-Grade Relative
Humidity and Temperature Sensor
Features
•
Relative humidity accuracy: up to ±2 %RH
•
Operating range: 0…100 %RH, -40…125 °C
•
Temperature accuracy: up to ±0.3 °C
•
Fully functional in condensing environment
•
Supply voltage: 2.3 V … 5.5 V
•
Variable power heater
•
I2C fast mode plus, CRC checksum
•
AEC Q100 qualification, high-reliability design
•
Pulse-width modulation interface
•
Mature technology from global market leader
•
Designed for 85°C/85%RH reliability testing
•
Patented protection options
General Description
SHT4xA is an automotive-grade digital sensor platform for measuring relative humidity and
temperature with different accuracy gradings. It fulfills demanding reliability requirements for
automotive applications, such as 85°C/85%RH accelerated life tests. The sensors can be
interfaced via I2C or pulse-width modulation. An integrated heater allows for advanced on-boarddiagnostics while the sensor element is designed for reliable operation in harsh conditions such
as condensing environments. The four-pin dual-flat-no-leads package is suitable for surface
mount technology (SMT) processing and can be ordered with a wettable flanks option.
Device Overview
Functional Block Diagram
Products
SHT40A-AD1B
SHT40A-FD1B
Details
base RH&T accur., 0x44 I2C addr.
base RH&T accur., PWM interface
base RH&T accur., 0x44 I2C addr.,
SHT40A-AW1B
wettable flanks
SHT41A-AD1B improved RH&T accur., 0x44 I2C addr.
improved RH&T accur., 0x44 I2C
SHT41A-AW1B
addr., wettable flanks
Full product list on page 17
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Contents
Features ........................................................................................................................................................................ 1
General Description ................................................................................................................................................... 1
Device Overview ......................................................................................................................................................... 1
Functional Block Diagram ........................................................................................................................................ 1
1 Quick Start – Hello World ..................................................................................................................................... 3
2 Humidity and Temperature Sensor Specifications ....................................................................................... 4
2.1 Relative Humidity ............................................................................................................................................4
2.2 Temperature .....................................................................................................................................................5
2.3 Recommended Operating Conditions ......................................................................................................6
3 Electrical Specifications ........................................................................................................................................ 6
3.1 Electrical Characteristics ..............................................................................................................................7
3.2 Timings ...............................................................................................................................................................8
3.3 Absolute Maximum Ratings .........................................................................................................................8
4 Sensor Operation .................................................................................................................................................... 9
4.1 I2C communication.........................................................................................................................................9
4.2 I2C Communication Timing .........................................................................................................................9
4.3 I2C Data type & length ..................................................................................................................................9
4.4 I2C Checksum Calculation...........................................................................................................................9
4.5 I2C Command Overview ............................................................................................................................10
4.6 I2C Conversion of Signal Output .............................................................................................................10
4.7 I2C Serial number .........................................................................................................................................11
4.8 I2C Heater Operation...................................................................................................................................11
4.9 Pulse-Width Modulation (PWM) interface .............................................................................................11
4.10 PWM Conversion of Signal Output .......................................................................................................12
4.11 Reset ..............................................................................................................................................................12
5 Physical Specification .......................................................................................................................................... 12
5.1 Package Description ....................................................................................................................................12
5.2 Package Outline – Standard Package ...................................................................................................13
5.3 Package Outline – Package with Wettable Flanks.............................................................................13
5.4 Land Pattern ...................................................................................................................................................14
5.5 Pin Assignment & Laser Marking.............................................................................................................15
5.6 Thermal Information .....................................................................................................................................15
6 Quality and Material Contents........................................................................................................................... 15
7 Tape and Reel Packaging .................................................................................................................................. 15
8 Product Name Nomenclature ............................................................................................................................ 16
9 Ordering Information ............................................................................................................................................ 17
10 Bibliography .......................................................................................................................................................... 17
11 Revision History .................................................................................................................................................. 17
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1 Quick Start – Hello World
A typical application circuit for SHT4xA is shown on the left-hand side of Figure 1. After reaching
the minimal supply voltage and allowing for the maximal power-up time of 1 ms the sensor is ready
for I2C communication. The quickest way to measure humidity and temperature is pseudo-coded
on the right-hand side of Figure 1. Together with the conversion formulae given in equations ( 1 ),
( 2 ), and ( 3 ), the digital signals can be translated into relative humidity and temperature readings.
Typical application circuit
Pseudo code
i2c_write(i2c_addr=0x44, tx_bytes=[0xFD])
wait_seconds(0.01)
rx_bytes = i2c_read(i2c_addr=0x44,
number_of_bytes=6)
t_ticks = rx_bytes[0] * 256 + rx_bytes[1]
checksum_t = rx_bytes[2]
rh_ticks = rx_bytes[3] * 256 + rx_bytes[4]
checksum_rh = rx_bytes[5]
t_degC = -45 + 175 * t_ticks/65535
rh_pRH = -6 + 125 * rh_ticks/65535
if (rh_pRH > 100):
rh_pRH = 100
if (rh_pRH < 0):
rh_pRH = 0
Figure 1: Typical application circuit (left) and pseudo code (right) for easy starting with the I2C
interface. For details on the signal cropping in the last four lines see section 4.6.
Find code resources and embedded drivers on: https://github.com/Sensirion/embeddedsht/releases
CAD files can be downloaded from SnapEDA (“*” considered as wildcard):
•
SHT4*A-*D*B
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2 Humidity and Temperature Sensor Specifications
Every SHT4xA is individually tested and calibrated and is identifiable by its unique serial number
(see section 4.7 for details on the serial number). For the calibration, Sensirion uses transfer
standards, which are subject to a scheduled calibration procedure. The calibration of the reference,
used for the calibration of the transfer standards, is NIST traceable through an ISO/IEC 17025
accredited laboratory.
2.1 Relative Humidity
Parameter
Conditions
typ.
SHT40A RH accuracy1
Value
3
see Figure 2
max.
typ.
SHT41A RH accuracy1
2
See Figure 3
0.08
0.15
0.21
0.01
max.
high
medium
low
At 25°C
Repeatability2
Resolution3
Hysteresis
range4
0.8
0 to 100
4
100 kΩ
0
-
10%VDD
V
-
PWM: Rload > 100 kΩ
90% VDD
-
VDD
V
-
I2C:
Rp ≥ 820 Ω: fast mode
-
-
400
pF
I2C:
Rp ≥ 390 Ω,
VDD ≥ 3.0 V: fast mode
plus
-
-
340
pF
PWM
0
-
1
nF
-
I2C:
VDD ≥ 2.3V, Rp ≥ 820 Ω
Low level output
voltage
High level output
voltage
Cap bus load
VOL
VOH
Cb
-
I2C:
VDD ≥ 3.0V, Rp ≥ 390 Ω
Capac. bus load can
be determined from
Cb < trise
/(0.8473*Rp).
Rise times are
trise = 300 ns for fast
mode and
trise = 120 ns for fast
mode plus
PWM frequency
1/tF
PWM
95
122
150
Hz
Base frequency
Measurement
frequency
-
PWM
-
2
-
Hz
Frequency with
which the sensor
acquires new values
Table 3: Electrical specifications.
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3.2 Timings
Parameter
Symbol
Conditions
Min.
Typ.
I2C:
Power-up time
tPU
After hard reset,
VDD ≥ VPOR
-
0.3
1
PWM:
Power-up time
tPU
After hard reset,
VDD ≥ VPOR
-
5
10
I2C:
Soft reset time
tSR
After soft reset
-
-
1
-
1.3
1.6
-
3.7
4.5
-
6.9
8.3
Long pulse
0.81
1
1.19
s
Short pulse
0.08
0.1
0.12
s
tMEAS,l
I2C:
Measurement
duration
tMEAS,m
tMEAS,h
I2C:
Heater-on duration
Low
repeatability
Med.
repeatability
High
repeatability
Max. Units
Comments
Time between VDD
reaching VPOR and
ms
sensor entering idle
state
Time between VDD
reaching VPOR and
ms
sensor providing
measurement data on
output pins
Time between ACK of
soft reset command and
ms
sensor entering idle
state. Also valid for I2C
general call reset.
ms
The three repeatability
modes differ with
ms respect to measurement
duration, noise level and
energy consumption
ms
tHeater
After that time the heater
is automatically switched
off
After that time the heater
is automatically switched
off
Table 4 System timing specifications.
3.3 Absolute Maximum Ratings
Stress levels beyond those listed in Table 5 may cause permanent damage or affect the reliability
of the device. These are stress ratings only and functional operation of the device at these
conditions is not guaranteed. Ratings are only tested each at a time.
Parameter
Supply voltage VDD
Max. voltage on any pin
Operating temperature range
Storage temperature range10
ESD HBM
ESD CDM
Latch up, JESD78 Class II, 125°C
Rating
-0.3 V … 6.0 V
VSS - 0.3 V … VDD + 0.3 V
-40 °C … 125 °C
-40 °C …150 °C
4 kV
750 V
+-100 mA
Table 5: Absolute maximum ratings.
10
The recommended storage temperature range is 10-50°C. Please consult (Sensirion, Handling Instructions for Humidity Sensors, 2020) for more information.
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4 Sensor Operation
4.1 I2C communication
I2C communication is based on NXP’s I2C-bus specification and user manual UM10204, Rev.6, 4
April 2014. Supported I2C modes are standard, fast mode, and fast mode plus. Data is transferred
in multiples of 16-bit words and 8-bit check sum (cyclic redundancy check = CRC). All transfers
must begin with a start condition (S) and terminate with a stop condition (P). To finish a read
transfer, send not acknowledge (NACK) and stop condition (P). Addressing a specific slave device
is done by sending its 7-bit I2C address followed by an eighth bit, denoting the communication
direction: “zero” indicates transmission to the slave, i.e. “write”, a “one” indicates a “read” request.
Schematics of the I2C transfer types are sketched in Figure 8.
Figure 8: I2C transfer types: First a write header is sent to the I2C slave, followed by a command,
for example “measure RH&T with highest precision”. After the measurement is finished the read
request directed to this I2C slave will be acknowledged and transmission of data will be started by
the slave.
4.2 I2C Communication Timing
All details on the timing are following the interface specification of NXP’s user manual UM10204,
Rev.6, 4 April 2014. Please follow mandatory capacitor and resistor requirements given in Table
3.
4.3 I2C Data type & length
I2C bus operates with 8-bit data packages. Information from the sensor to the master has a
checksum after every second 8-bit data package.
Humidity and temperature data will always be transmitted in the following way: The first value is
the temperature signal (2 * 8-bit data + 8-bit CRC), the second is the humidity signal (2 * 8-bit data
+ 8-bit CRC).
4.4 I2C Checksum Calculation
For read transfers each 16-bit data is followed by a checksum with the following properties
Property
Name
Message Length
Polynomial
Initialization
Value
CRC-8
16-bit
8
0x31 (x + x5 + x4 +1)
0xFF
Reflect Input/Output
Final XOR
Examples
false/false
0x00
CRC(0xBEEF) = 0x92
Table 6 Data check sum properties.
The master may abort a read transfer after the 16-bit data if it does not require a checksum.
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4.5 I2C Command Overview
Command
(hex)
Response length
incl. CRC (bytes)
0xFD
6
0xF6
6
0xE0
6
0x89
6
0x94
-
0x39
6
0x32
6
0x2F
6
0x24
6
0x1E
6
0x15
6
Description
[return values]
measure T & RH with high precision (high repeatability)
[2 * 8-bit T-data; 8-bit CRC; 2 * 8-bit RH-data; 8-bit CRC]
measure T & RH with medium precision (medium repeatability)
[2 * 8-bit T-data; 8-bit CRC; 2 * 8-bit RH-data; 8-bit CRC]
measure T & RH with lowest precision (low repeatability)
[2 * 8-bit T-data; 8-bit CRC; 2 * 8-bit RH-data; 8-bit CRC]
read serial number
[2 * 8-bit data; 8-bit CRC; 2 * 8-bit data; 8-bit CRC]
soft reset
[ACK]
activate heater with 200mW for 1s, including a high precision
measurement just before deactivation
[2 * 8-bit T-data; 8-bit CRC; 2 * 8-bit RH-data; 8-bit CRC]
activate heater with 200mW for 0.1s including a high precision
measurement just before deactivation
[2 * 8-bit T-data; 8-bit CRC; 2 * 8-bit RH-data; 8-bit CRC]
activate heater with 110mW for 1s including a high precision
measurement just before deactivation
[2 * 8-bit T-data; 8-bit CRC; 2 * 8-bit RH-data; 8-bit CRC]
activate heater with 110mW for 0.1s including a high precision
measurement just before deactivation
[2 * 8-bit T-data; 8-bit CRC; 2 * 8-bit RH-data; 8-bit CRC]
activate heater with 20mW for 1s including a high precision
measurement just before deactivation
[2 * 8-bit T-data; 8-bit CRC; 2 * 8-bit RH-data; 8-bit CRC]
activate heater with 20mW for 0.1s including a high precision
measurement just before deactivation
[2 * 8-bit T-data; 8-bit CRC; 2 * 8-bit RH-data; 8-bit CRC]
Table 7 Overview of I2C commands. If the sensor is not ready to process a command, e.g. because it is still
measuring, it will return NACK to the I2C read header. Given heater power values are typical and valid for
VDD=5V. At VDD=3.3V, heating power is reduced to 5% of the nominal value.
4.6 I2C Conversion of Signal Output
The digital sensor signals correspond to following humidity and temperature values:
𝑆𝑅𝐻
𝑅𝐻 = (−6 + 125 ∙ 16
) %RH
2 −1
𝑆𝑇
𝑇 = (−45 + 175 ∙ 16
) °C
2 −1
𝑆𝑇
𝑇 = (−49 + 315 ∙ 16
) °F
2 −1
(1)
(2)
(3)
N.B.: The RH conversion formula (1) allows values to be reported which are outside of the range
of 0 %RH … 100 %RH. Relative humidity values which are smaller than 0 %RH and larger than
100 %RH are non-physical, however these “uncropped” values might be found beneficial in some
cases (e.g. when the distribution of the sensors at the measurement boundaries are of interest).
For all users who don’t want to engage in evaluation of these non-physical values, cropping of the
RH signal to the range of 0 %RH … 100 %RH is advised.
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4.7 I2C Serial number
Every single sensor has a unique serial number, that is assigned by Sensirion during production.
It is stored in the one-time-programmable memory and cannot be manipulated after production.
The serial number is accessible via I2C and is transmitted as two 16-bit words, each followed by
an 8-bit CRC.
4.8 I2C Heater Operation
The sensor incorporates an integrated on-chip heater which can be switched on by the set of
commands given in Table 7. There are three different heating powers and two different heating
times accessible to the user. After reception of a heater-on command, the sensor executes the
following procedure:
1. The heater is enabled, and the timer starts its count-down.
2. On timer expiration a temperature and humidity measurement with the highest repeatability
is started, the heater remains enabled.
3. After the measurement is finished the heater is turned off.
4. Temperature and humidity values are now available for readout.
The maximum on-time of the heater commands is 1 second in order to prevent overheating of the
sensor by unintended usage of the heater. Thus, there is no dedicated command to turn off the
heater. For extended heating periods it is required to send periodic heater-on commands, keeping
in mind that the heater is designed for a maximal duty cycle of less than 10%. To obtain a fast
increase in temperature the idle time between consecutive heating pulses shall be kept minimal.
Possible Heater Use Cases
Please refer to the dedicated Sensirion application notes elaborating on various use cases of the
heater. In general, the applications of the on-chip heater cover:
1. Removal of condensed / spray water on the sensor surface. Although condensed water is
not a reliability / quality problem to the sensor, it will however make the sensor nonresponsive to RH changes in the air as long as there is liquid water on the surface.
2. Drift-free operation in high humid environments. Periodic heating pulses allow for drift-free
high-humidity measurements over extended periods of times.
Important notes for operating the heater:
1. The heater is designed for a maximum duty cycle of 10%, meaning the total heater-ontime should not be longer than 10% of the sensor’s lifetime.
2. During operation of the heater, sensor specifications are not valid.
3. The temperature sensor can additionally be affected by the thermally induced mechanical
stress, offsetting the temperature reading from the actual temperature.
4. The sensor’s temperature (base temperature + temperature increase from heater) must
not exceed Tmax = 125 °C to have proper electrical functionality of the chip.
5. The heater draws a large amount of current once enabled (up to ~50mA in the highest
power setting). Although a dedicated circuitry draws this current smoothly, the power
supply must be strong enough to avoid large voltage drops that could provoke a sensor
reset.
6. If higher heating temperatures are desired, consecutive heating commands can be sent to
the sensor. To keep times between consecutive heating pulses minimal, polling of the
sensor is advised. The heater shall only be operated in ambient temperatures below 65°C
else it could drive the sensor outside of its maximal operating temperature.
4.9 Pulse-Width Modulation (PWM) interface
The sensor can be ordered with a pre-configured pulse width modulation (PWM) interface. This is
a permanent interface configuration and cannot be changed by the user.
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After power-up of the sensor, it needs at most 10 ms until providing measurement data as PWM
bit-stream on the respective output pins (see Figure 13). During that time the temperature and
humidity pins have an undefined state.
The PWM is based on a constant base frequency with period tF, as shown in Figure 9. The
humidity and temperature signals are provided as duty cycle (tPW/tF) on that base frequency. A
ratio of e.g. tPW_RH/tF = 0.1 corresponds to RH = -6 %RH while a ratio of e.g. tPW_RH/tF = 0.9
corresponds to RH = 119 %RH.
tF
tPW
VDD
0V
Figure 9 PWM signal: The base frequency of 1/tF remains constant, whereas tPW is variable. The physical
signal of temperature and humidity is provided as tPW/tF on the respective pins.
4.10 PWM Conversion of Signal Output
Measurement data is linearized and compensated for temperature and supply voltage effects by
the sensor. The provided pulse widths tPW_RH and tPW_Temp are translated into humidity and
temperature values by the following formulae, respectively:
𝑡PW_RH
(4)
𝑅𝐻 = (−21.625 + 156.25 ∙
) %RH
𝑡F
17.5 175 𝑡𝑃𝑊_Temp
(5)
𝑇 = (− 45 −
+
⋅
) °C
0.8
0.8
𝑡𝐹
31.5 315 𝑡𝑃𝑊_Temp
(6)
𝑇 = (− 49 −
+
⋅
) °F
0.8
0.8
𝑡𝐹
4.11 Reset
A reset of the sensor can be achieved in three ways:
•
I2C Soft reset: send the reset command described in Table 7.
•
I2C general call: all devices on I2C bus are reset by sending the command 0x06 to the I2C
address 0x00.
•
Power down (incl. pulling SCL and SDA low)
5 Physical Specification
5.1 Package Description
SHT4xA is provided in an open-cavity dual flat no lead (DFN) package. The humidity sensor
opening is centered on the top side of the package. The sensor chip is made of silicon, hosted on
a copper lead frame and overmolded by an epoxy-based mold compound. Exposed bottom side of
the leadframe with the metallic contacts is Ni/Pd/Au coated, side walls are bare copper.
Moisture sensitivity level (MSL) of 1 according to IPC/JEDEC J-STD-020 is achieved. It is
recommended to process the sensors within one year after date of delivery.
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5.2 Package Outline – Standard Package
Figure 10 Dimensional drawing of SHT4xA including package tolerances (units mm).
5.3 Package Outline – Package with Wettable Flanks
Figure 11 Dimensional drawing of SHT4xA with wettable flanks, including package tolerances (units mm).
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5.4 Land Pattern
The land pattern is recommended to be designed according to the used PCB and soldering process
together with the physical outer dimensions of the sensor. For reference, the land pattern used with
Sensirion’s PCBs and soldering processes is given in Figure 12. It is suitable for the DFN with
wettable flanks and without wettable-flanks option.
Sensirion recommends to not solder the central die pad because the sensor can reach higher
temperatures upon heater activation.
Figure 12: Recommended land pattern (in
mm). Details can vary and depend on used
PCBs and solder processes. There shall be
no copper under the sensor other than at
the pin pads.
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5.5 Pin Assignment & Laser Marking
Pin
Name
I2C
PWM
1
SDA
RH
2
SCL
T
3
4
VDD
VSS
Comments
I2C
PWM
Serial data,
RH out
bidirectional
Serial clock,
T out
unidirectional input
Supply voltage
Ground
Figure 13 Pin assignment (transparent top view). Dashed lines are only visible if sensor is viewed
from below. The die pad is not directly connected to any pin.
The laser marking consists of two lines, indicated in Figure 13. In the first line a filled circle serves
as pin-1 indicator and is followed by “SH4”. The fourth character will indicate the accuracy class
of this product (here “x” serves as place holder). Last “A” indicates the automotive grade. In the
second line, the first three characters specify the product characteristics according to positions 8,
9 and 10 of Table 9. The second three characters serve as internal batch tracking code.
5.6 Thermal Information
Symbol
Description
𝑅𝜃𝐽𝐴
Junction-to-ambie.
thermal resistance
Junction-to-case
thermal resistance
Junction-to-board
thermal resistance
Junction-to-board
characteriz. param.
Junction-to-top
characteriz. param.
𝑅𝜃𝐽𝐶
𝑅𝜃𝐽𝐵
Ψ𝐽𝐵
Ψ𝐽𝑇
Heater off, die pad Heater on, die pad Heater off, die pad Heater on, die pad
soldered (K/W)
soldered (K/W) not solder. (K/W) not solder. (K/W)
DFN
DFN+WF
DFN
DFN+WF
DFN
DFN+WF
DFN
DFN+WF
246
258
308
329
297
322
357
390
189
183
255
252
191
188
257
254
159
177
225
242
193
219
258
284
159
171
223
242
191
213
254
282
38
35
105
104
44
42
112
111
Table 8 Typical values for thermal metrics. In the “heater on” columns a heater power of 200 mW was
assumed. Soldering of the die pad is not recommended, therefore the two right hand side columns are bold.
The sub-columns labelled “DFN+WF” display the results for the DFN package with soldered wettable flanks
terminals. Values are based on simulation.
6 Quality and Material Contents
Qualification of SHT4xA is performed based on the AEC Q100 qualification test method.
Qualification pending. The device is fully RoHS and WEEE compliant, e.g. free of Pb, Cd, and
Hg. For general remarks of best practice in processing humidity sensor please refer to (Sensirion,
Handling Instructions for Humidity Sensors, 2020).
7 Tape and Reel Packaging
All specifications for the tape and reel packaging can be found on Figure 14. Reel diameters are
13 inch and 8 inch for the 10k and the 2.5k packaging sizes, respectively.
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Figure 14: Tape and reel specifications including sensor orientation in pocket (see indication of two sensors
on the right side of the tape).
8 Product Name Nomenclature
position
1
2
3
4
5
6
7
8
9
value(s)
S
H
T
4
0
1
A
A
B
F
explanation
Sensirion
humidity signal
temperature signal
fourth product generation
base accuracy
improved accuracy
automotive version
delimiter
I2C interface with 0x44 address
I2C interface with 0x45 address
PWM Interface
D
W
DFN package
DFN package with wettable flanks
1
B
R
2
3
reserved
blank package without membrane
delimiter
tape on reel packaging
reel contains 2’500 pieces
reel contains 10’000 pieces
10
11
12
13
14
Table 9 SHT4xA product name nomenclature.
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9 Ordering Information
Material Description
SHT40A-AD1B-R2
SHT40A-AD1B-R3
SHT40A-FD1B-R2
SHT40A-FD1B-R3
Material Number
3.000.546
3.000.672
3.000.676
3.000.673
SHT40A-AW1B-R2
3.000.677
SHT40A-AW1B-R3
3.000.674
SHT41A-AD1B-R2
SHT41A-AD1B-R3
3.000.551
3.000.624
SHT41A-AW1B-R2
3.000.552
SHT41A-AW1B-R3
3.000.675
Details
base RH&T accuracy, 0x44 I2C addr.
base RH&T accuracy, 0x44 I2C addr.
base RH&T accuracy, PWM interface
base RH&T accuracy, PWM interface
base RH&T accuracy, 0x44 I2C addr.,
wettable flanks
base RH&T accuracy, 0x44 I2C addr.,
wettable flanks
improved RH&T accuracy, 0x44 I2C addr.
improved RH&T accuracy, 0x44 I2C addr.
improved RH&T accuracy, 0x44 I2C addr.,
wettable flanks
improved RH&T accuracy, 0x44 I2C addr.,
wettable flanks
Quantity (pcs)
2’500
10’000
2’500
10’000
2’500
10’000
2’500
10’000
2’500
10’000
Table 10 SHT4xA ordering options.
10 Bibliography
Sensirion. (2020). Handling Instructions for Humidity Sensors. Retrieved from www.sensirion.com
11 Revision History
Date
January 2022
Version
1
July 2022
2
Page(s)
All
4
7
12
3
6
10
13
www.sensirion.com / D1
Changes
First release
Updated drift specification in Table 1
Updated max. current in Table 3
Updated formula (4) and PWM description
Added SnapEDA link in section 1
Corrected typo in caption of Figure 7
Corrected erratum in caption of Table 7:
old: “… valid for VDD=3.3V” new: “… valid for VDD=5V”
Introduced new section 5.3 describing wettable flanks pack.
Version 2 – July 2022
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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 © 2022, by SENSIRION. CMOSens® is a trademark of Sensirion. All rights reserved
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phone: +81 3 3444 4940
info-jp@sensirion.com
www.sensirion.com/jp
Sensirion China Co. Ltd.
phone: +86 755 8252 1501
info-cn@sensirion.com
www.sensirion.com/cn
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phone: +886 3 5506701
info@sensirion.com
www.sensirion.com
www.sensirion.com / D1
To find your local representative, please visit www.sensirion.com/distributors
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