www.sensirion.com May 2015 - Version 0.93 1/13
Datasheet SHT3x-ARP
Humidity and Temperature Sensor
Fully calibrated, linearized, and temperature
compensated analog output
Wide supply voltage range, from 2.4 to 5.5 V
10 to 90% ratiometric analog voltage output
Typical accuracy of 2%RH and 0.3°C
Parallel measurement of temperature and humidity
at separate pins
Tiny 8-Pin DFN package
Product Summary
SHT3x-ARP is the next generation of Sensirion’s
temperature and humidity sensors. It builds on a new
CMOSens® sensor chip that is at the heart of Sensirion’s
new humidity and temperature platform. The SHT3x-
ARP has increased intelligence, reliability and improved
accuracy specifications compared to its predecessor. Its
functionality includes enhanced signal processing,
temperature and humidity can be read out at different
pins. The DFN package has a footprint of 2.5 x 2.5 mm
while keeping a height of 0.9 mm. This allows for
integration of the SHT3x-ARP into a great variety of
applications. Additionally, the wide supply voltage range
of 2.4 to 5.5 V guarantees compatibility with diverse
assembly situations. All in all, the SHT3x-ARP
incorporates 15 years of knowledge of Sensirion, the
leader in the humidity sensor industry.
Benefits of Sensirion’s CMOSens® Technology
High reliability and long-term stability
Industry-proven technology with a track record of
more than 15 years
Designed for mass production
High process capability
Low signal noise
Content
1 Sensor Performance............................................. 2
2 Specifications ....................................................... 4
3 Pin Assignment .................................................... 6
4 Operation and Communication ............................. 6
5 Packaging ............................................................. 8
6 Shipping Package .............................................. 10
7 Quality ................................................................ 11
8 Ordering Information........................................... 11
9 Further Information ............................................. 11
Figure 1 Functional block diagram of the SHT3x-ARP. The
sensor signals for humidity and temperature are factory
calibrated, linearized and compensated for temperature
and supply voltage dependencies.
Datasheet SHT3x-ARP
www.sensirion.com May 2015 - Version 0.93 2/13
1 Sensor Performance
1.1 Humidity Sensor Performance
Parameter
Conditions
Value
Units
SHT30 Accuracy tolerance1
Typ.
3
%RH
Max.
Figure 2
%RH
SHT31 Accuracy tolerance1
Typ.
2
%RH
Max.
Figure 4
%RH
Repeatability2
0.1
%RH
Resolution
14
bit
Integrated Non-Linearity3
Max.
0.2
%RH
Hysteresis
at 25°C
0.8
%RH
Specified range4
extended5
0 to 100
%RH
Response time6
63%
8
s
Long-term drift
Typ.7
<0.25
%RH/yr
Sensitivity
VDD=2.4V
19.2
mV/%RH
VDD=3.3V
26.4
mV/%RH
VDD=5.5V
44
mV/%RH
Table 1 Humidity sensor specification
Relative Humidity (%RH)
100
±4.5
±4.5
±4.5
±4.5
±4.5
±4.5
±4.5
±4.5
±4.5
90
±3
±3
±3
±3
±3
±3
±3
±3
±3
80
±3
±3
±3
±3
±3
±3
±3
±3
±3
70
±3
±3
±3
±3
±3
±3
±3
±3
±3
60
±3
±3
±3
±3
±3
±3
±3
±3
±3
50
±3
±3
±3
±3
±3
±3
±3
±3
±3
40
±3
±3
±3
±3
±3
±3
±3
±3
±3
30
±3
±3
±3
±3
±3
±3
±3
±3
±3
20
±3
±3
±3
±3
±3
±3
±3
±3
±3
10
±3
±3
±3
±3
±3
±3
±3
±3
±3
0
±4.5
±4.5
±4.5
±4.5
±4.5
±4.5
±4.5
±4.5
±4.5
0
10
20
30
40
50
60
70
80
SHT30
Temperature (°C)
Figure 2 Tolerance of RH at 25°C for SHT30
Figure 3 Typical tolerance of RH over T for SHT30
1
For definition of typical and maximum accuracy tolerance, please refer to the document “Sensirion Humidity Sensor Specification Statement”.
2
The stated repeatability is 3 times the standard deviation (3σ) of multiple consecutive measurements at constant ambient conditions. It is a measure for the noise on
the physical sensor output. It is measured with analog circuit and integrated over 1 second.
3
Maximum deviation from the ideal shape (linear curve)
4
Specified range refers to the range for which the humidity or temperature sensor specification is guaranteed.
5
For details about recommended humidity and temperature operating range, please refer to section 0.
6
Time for achieving 63% of a humidity step function, valid at 25°C and 1m/s airflow. Humidity response time in the application depends on the design-in of the sensor.
7
Typical value for operation in normal RH/T operating range, see section 1.3. Maximum value is < 0.5 %RH/yr. Value may be higher in environments with vaporized
solvents, out-gassing tapes, adhesives, packaging materials, etc. For more details please refer to Handling Instructions.
±0
±2
±4
±6
±8
010 20 30 40 50 60 70 80 90 100
Relative Humidity (%RH)
SHT30
maximal tolerance
typical tolerance
DRH (%RH)
Datasheet SHT3x-ARP
www.sensirion.com May 2015 - Version 0.93 3/13
Relative Humidity (%RH)
100
±2
±2
±2
±2
±2
±2
±2
±2
±2
90
±2
±2
±2
±2
±2
±2
±2
±2
±2
80
±2
±2
±2
±2
±2
±2
±2
±2
±2
70
±2
±2
±2
±2
±2
±2
±2
±2
±2
60
±2
±2
±2
±2
±2
±2
±2
±2
±2
50
±2
±2
±2
±2
±2
±2
±2
±2
±2
40
±2
±2
±2
±2
±2
±2
±2
±2
±2
30
±2
±2
±2
±2
±2
±2
±2
±2
±2
20
±2
±2
±2
±2
±2
±2
±2
±2
±2
10
±2
±2
±2
±2
±2
±2
±2
±2
±2
0
±2
±2
±2
±2
±2
±2
±2
±2
±2
0
10
20
30
40
50
60
70
80
SHT31
Temperature (°C)
Figure 4 Tolerance of RH at 25°C for SHT31
Figure 5 Typical tolerance of RH over T for SHT31
±0
±2
±4
±6
±8
010 20 30 40 50 60 70 80 90 100
Relative Humidity (%RH)
SHT31
maximal tolerance
typical tolerance
DRH (%RH)
Datasheet SHT3x-ARP
www.sensirion.com May 2015 - Version 0.93 4/13
1.2 Temperature Sensor Performance
Parameter
Condition
Value
Units
Accuracy tolerance1
Typ. 10 to +55
0.3
°C
Repeatability2
0.1
°C
Resolution
Typ.
14
bit
Specified Range
-
-40 to 125
°C
Response time 8
63%
>2
s
Long Term Drift
max.
<0.03
°C/yr
Sensitivity
VDD=2.4V
11.6
mV/°C
VDD=3.3V
16
mV/°C
VDD=5.5V
26.7
mV/°C
Table 2 Temperature sensor specification; values are target specs and not
confirmed by measurements yet
Figure 6 Tolerance of the temperature sensor in °C for the SHT30 and SHT31
1.3 Recommended Operating Condition
The sensor shows best performance when operated within recommended normal temperature and humidity range of 5 –
60 °C and 20 – 80 %RH, respectively. Long term exposure to conditions outside normal range, especially at high humidity,
may temporarily offset the RH signal (e.g.+3%RH after 60h at >80%RH). After returning into the normal temperature and
humidity range the sensor will slowly come back to calibration state by itself. Prolonged exposure to extreme conditions
may accelerate ageing. To ensure stable operation of the humidity sensor, the conditions described in the document
“SHTxx Assembly of SMD Packages”, section “Storage and Handling Instructions” regarding exposure to volatile organic
compounds have to be met. Please note as well that this does apply not only to transportation and manufacturing, but also
to operation of the SHT3x-ARP.
2 Specifications
2.1 Electrical Specifications
Parameter
Symbol
Condition
Min
Typ.
Max
Units
Comments
Supply voltage
VDD
2.4
3.3
5.5
V
Power-up/down level
VPOR
2.2
2.28
2.35
V
8
Temperature response times strongly depends on the design-in of the sensor in the final application. Minimal response time can be achieved when the thermalized
sensor at T1 is placed on a well conducting surface with temperature T2.
±0.0
±0.5
±1.0
±1.5
±2.0
-40 -20 0 20 40 60 80 100 120
Temperature (°C)
SHT30/SHT31
maximal tolerance
typical tolerance
DT (°C)DT (°C)DT (°C)DT (°C)DT (°C)DT (°C)
Datasheet SHT3x-ARP
www.sensirion.com May 2015 - Version 0.93 5/13
Slew rate change of the
supply voltage
VDDslew
20
V/ms
Voltage changes on the
VDD line between VDD
min and VDD max should
be below the maximum
slew rate
Supply current
IDD
Average
220
350
A
At a measurement rate
of 2 Hz.
Depends on the resistive
load on the output pins
Output current
AOIOUT
-100
100
A
Capacitive load
CL
5
nF
Capacitance that can be
driven by the sensor on
the signal lines
Table 3 Electrical specifications, Specification are valid at 25°C and typical VDD
2.2 Timing Specification for the Sensor System
Parameter
Symbol
Conditions
Min.
Typ.
Max.
Units
Comments
Power-up time
tPU
After hard reset,
VDD ≥ VPOR
17
ms
Time between VDD reaching
VPOR and first measurement
signal available
Analog output settling time
AOsettle
For a step of VDD/2
0.3
1
ms
Time needed for adapting to a
changing supply voltage and
measurement value. Value
depends on output load.
Typical value is for a load of
1nF.
Duration of reset pulse
tRESETN
350
ns
See section 3.3
Table 4 System Timing Specification, Specification are valid at 25°C and typical VDD
2.3 Absolute Minimum and Maximum Ratings
Stress levels beyond those listed in Table 5 may cause permanent damage to the device or affect the reliability of the
sensor. These are stress ratings only and functional operation of the device at these conditions cannot be guaranteed.
Parameter
Rating
Units
Supply voltage VDD
-0.3 to 6
V
Max Voltage on pins (pin 1 (RH); pin 2
(R); pin 3 (R); pin 4(T); pin 6(nRESET))
-0.3 to VDD+0.3
V
Input current on any pin
±100
mA
Operating temperature range
-40 to 125
°C
Storage temperature range
-40 to 150
°C
ESD HBM (human body model)
4
kV
ESD CDM (charge device model)
750
V
Table 5 Absolute minimum and maximum ratings; values are target specs and not
confirmed by measurements yet
Datasheet SHT3x-ARP
www.sensirion.com May 2015 - Version 0.93 6/13
3 Pin Assignment
The SHT3x-ARP comes in a tiny 8-pin DFN package –
see Table 6.
Pin
Name
Comments
1
RH
Analog voltage out; output
2
R
No electrical function; recommended to
connect to VSS
3
R
No electrical function; recommended to
connect to VSS
4
T
Analog voltage out; output
5
VDD
Supply voltage; input
6
nRESET
Reset pin active low; Input; if not used it
is recommended to connect to VDD
7
R
No electrical function; recommended to
connect to VSS
8
VSS
Ground
Table 6 SHT3x-ARP pin assignment (Transparent top view).
Dashed lines are only visible from the bottom. The die pad is
internally connected to VSS.
3.1 Power Pins (VDD, VSS)
The electrical specifications of the SHT3x-ARP are
shown in Table 3. The power supply pins must be
decoupled with a 100 nF capacitor that shall be placed
as close to the sensor as possible – see Figure 7 for a
typical application circuit.
3.2 Temperature and Humidity Pin
The physical output of temperature and humidity can be
read out at separated pins, as shown in Table 6. Data is
supplied as ratiometric voltage output. The specification
of the Analog voltage signal and its conversion to
physical values is explained in Section 4.
3.3 nRESET Pin
The nReset pin may be used to generate a reset of the
sensor. A minimum pulse duration of 350 ns is required
to reliably trigger a reset of the sensor. If not used it is
recommended to connect to VDD.
Figure 7 Typical application circuit. Please note that the
positioning of the pins does not reflect the position on the
real sensor. This is shown in Table 6.
3.4 Die Pad (center pad)
The die pad or center pad is visible from below and
located in the center of the package. It is electrically
connected to VSS. Hence electrical considerations do
not impose constraints on the wiring of the die pad.
However, due to mechanical reasons it is recommended
to solder the center pad to the PCB. For more
information on design-in, please refer to the document
“SHTxx Design Guide”.
4 Operation and Communication
4.1 Start-up of the sensor
As a first step, the sensor needs to be powered up to
VDD (between 2.4 and 5.5 V). After power-up, the
sensor needs at most 17 ms for providing data as voltage
output on the respective output pins. During that time the
temperature and humidity pins have an undefined state.
4.2 Conversion of the Signal Output
The physical values as measured by the sensor are
mapped to a ratiometric voltage output (VX, x=T, RH as
10 to 90% of VDD). Prior to conversion into a voltage
signal, the physical values are linearized and
compensated for temperature and supply voltage effects
by the sensor. Additionally, the voltage output is
calibrated for each sensor. Hence the relationship
between temperature and humidity and the voltage
output is the same for each sensor, within the limits given
by the accuracy.
This allows to describe the relationship between physical
values (RH and T) and the voltage output for
temperature and humidity (VX, x=T, RH) through a
generic linear formula shown in Equation 1 (for RH) and
Equation 2 (for T), its graphical representation can be
found in Figure 8 & Figure 9.
1
2
3
45
8
7
6
VDD
R(2,3,7)
RH(1)
T(4)
VDD(5)
VSS(8) die
pad
100nF
nRESET(6)
0.1nF
0.1nF
Datasheet SHT3x-ARP
www.sensirion.com May 2015 - Version 0.93 7/13
Figure 8 Relationship between the ratiometric analog voltage output and the measured relative humidity
Figure 9 Relationship between the ratiometric analog voltage output and the measured temperature
0
10
20
30
40
50
60
70
80
90
100
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Relative Humidity (%)
Voltage out (VRH/VDD)
-49
1
51
101
151
201
251
-45
-25
-5
15
35
55
75
95
115
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Temperature (°F)
Temperature (°C)
Voltage out (VT/VDD)
DD
RH
DD
RH
V
V
V
V
0.8
100
0.8
10
12512.5 RH
Equation 1 Relative humidity conversion formula (result in %RH):
DD
T
DD
T
DD
T
DD
T
V
V
V
V
88.375 F
V
V
V
V
66.875
0.8
315
0.8
31.5
49 75.393 T
0.8
175
0.8
17.5
45 75.218 C T
Equation 2 Temperature conversion formula (result in °C and °F respectively)
Datasheet SHT3x-ARP
www.sensirion.com May 2015 - Version 0.93 8/13
5 Packaging
SHT3x-ARP sensors are provided in a DFN package.
DFN stands for dual flat no leads. The humidity sensor
opening is centered on the top side of the package.
The sensor chip is made of silicon and is mounted to a
lead frame. The latter is made of Cu plated with
Ni/Pd/Au. Chip and lead frame are overmolded by an
epoxy-based mold compound leaving the central die pad
and I/O pins exposed for mechanical and electrical
connection. Please note that the side walls of the sensor
are diced and therefore these diced lead frame surfaces
are not covered with the respective plating.
The package (except for the humidity sensor opening)
follows JEDEC publication 95, design registration 4.20,
small scale plastic quad and dual inline, square and
rectangular, No-LEAD packages (with optional thermal
enhancements) small scale (QFN/SON), Issue D.01,
September 2009.
5.1 Traceability
All SHT3x-ARP sensors are laser marked for easy
identification and traceability. The marking on the sensor
top side consists of a pin-1 indicator and two lines of text.
The top line consist of the pin-1 indicator which is located
in the top left corner and the product name. The small
letter x stands for the accuracy class.
The bottom line consists of 6 letters. The first two digits
XY (=AR) describe the output mode. The third letter (A)
represents the manufacturing year (4 = 2014, 5 = 2015,
etc). The last three digits (BCD) 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.
If viewed from below pin 1 is indicated by triangular
shaped cut in the otherwise rectangular die pad. The
dimensions of the triangular cut are shown in Figure 11
through the labels T1 & T2.
Figure 10 Top View of the SHT3x-ARP illustrating the laser
marking.
.
XYABCD
SHT3x
Datasheet SHT3x-ARP
www.sensirion.com May 2015 - Version 0.93 9/13
5.2 Package Outline
Figure 11 Dimensional drawing of SHT3x-ARP sensor package
Parameter
Symbol
Min
Nom.
Max
Units
Comments
Package height
A
0.8
0.9
1
mm
Leadframe height
A3
0.2
mm
Not shown in the drawing
Pad width
b
0.2
0.25
0.3
mm
Package width
D
2.4
2.5
2.6
mm
Center pad length
D2
1
1.1
1.2
mm
Package length
E
2.4
2.5
2.6
mm
Center pad width
E2
1.7
1.8
1.9
mm
Pad pitch
e
0.5
mm
Pad length
L
0.3
0.35
0.4
mm
Max cavity
S
1.5
mm
Only as guidance. This value includes all tolerances,
including displacement tolerances. Typically the
opening will be smaller.
Center pad marking
T1xT2
0.3x45°
mm
indicates the position of pin 1
Table 7 Package outline
5.3 Land Pattern
Figure 12 shows the land pattern. The land pattern is
understood to be the metal layer on the PCB, onto which
the DFN pads are soldered.
The solder mask is understood to be the insulating layer
on top of the PCB covering the copper traces. It is
recommended to design the solder mask as a Non-
Solder Mask Defined (NSMD) type. For NSMD pads, the
solder mask opening should provide a 60 μm to 75 μm
design clearance between any copper pad and solder
mask. As the pad pitch is only 0.5 mm we recommend to
have one solder mask opening for all 4 I/O pads on one
side.
For solder paste printing it is recommended to use a
laser-cut, stainless steel stencil with electro-polished
trapezoidal walls and with 0.1 or 0.125 mm stencil
thickness. The length of the stencil apertures for the I/O
pads should be the same as the PCB pads. However,
the position of the stencil apertures should have an offset
of 0.1 mm away from the center of the package. The die
pad aperture should cover about 70 – 90 % of the die
pad area –thus it should have a size of about 0.9 mm x
1.6 mm.
For information on the soldering process and further
recommendation on the assembly process please
consult the Application Note
HT_AN_SHTxx_Assembly_of_SMD_Packages , which
can be found on the Sensirion webpage.
E
D
S
A
e
b
D2
E2
L
T1 x T2
Datasheet SHT3x-ARP
www.sensirion.com May 2015 - Version 0.93 10/13
Figure 12 Recommended metal land pattern and stencil apertures for the SHT3x-ARP. The dashed lines represent the outer
dimension of the DFN package. The PCB pads and stencil apertures are indicated through the shaded areas.
6 Shipping Package
Figure 13 Technical drawing of the packaging tape with sensor orientation in tape. Header tape is to the right and trailer tape to the
left on this drawing. Dimensions are given in millimeters.
1.7
0.25
1
0.5
0.5
0.5
0.55
0.3x45°
0.375
0.2
0.75
0.4
0.9
1.6
0.55
0.5 0.5 0.5
0.25
0.55
0.45
0.8
0.375
0.3
land pattern stencil aperture
sensor outline
TOLERANCES - UNLESS
NOTED 1PL ±.2 2PL ±.10
A = 2.75
B = 2.75
K = 1.20
0
0
0
NOTES:
1. 10 SPROCKET HOLE PITCH CUMULATIVE TOLERANCE ±0.2
2. POCKET POSITION RELATIVE TO SPROCKET HOLE MEASURED
AS TRUE POSITION OF POCKET, NOT POCKET HOLE
3. A0 AND B0 ARE CALCULATED ON A PLANE AT A DISTANCE "R"
ABOVE THE BOTTOM OF THE POCKET
A0
K0
B0
R 0.25 TYP.
SECTION A - A
0.30 ±.05
A
R 0.2 MAX.
0.30 ±.05
2.00 ±.05 SEE Note 2 4.00
4.00 SEE Note 1
Ø1.5 +.1 /-0.0
Ø1.00 MIN 1.75 ±.1
12.0 +0.3/-0.1
5.50 ±.05
SEE NOTE 2
A
B
DETAIL B
Datasheet SHT3x-ARP
www.sensirion.com May 2015 - Version 0.93 11/13
7 Quality
Qualification of the SHT3x-ARP is performed based on
the AEC Q 100 qualification test method.
7.1 Material Contents
The device is fully RoHS and WEEE compliant, e.g. free
of Pb, Cd, and Hg.
8 Ordering Information
The SHT3x-ARP can be ordered in tape and reel
packaging with different sizes, see Table 8. The reels are
sealed into antistatic ESD bags. The document (SHT3x
shipping package) that shows the packaging tape with
sensor orientation is available upon request.
Name
Quantity
Order Number
SHT30-ARP-B500E
500
1-101250-01
SHT30-ARP-B10kS
10000
1-101175-01
SHT31-ARP-B1kS
1000
1-101257-01
SHT31-ARP-B10kS
10000
1-101178-01
Table 8 SHT3x-ARP ordering options.
9 Further Information
For more in-depth information on the SHT3x-ARP and its
application please consult the following documents:
Document Name
Description
Source
SHT3x Shipping Package
Information on Tape, Reel and shipping bags
(technical drawing and dimensions)
Available upon request
SHTxx Assembly of SMD
Packages
Assembly Guide (Soldering Instruction,)
Available for download at the Sensirion
humidity sensors download center:
www.sensirion.com/humidity-download
SHTxx Design Guide
Design guidelines for designing SHTxx humidity
sensors into applications
Available for download at the Sensirion
humidity sensors download center:
www.sensirion.com/humidity-download
SHTxx Handling Instructions
Guidelines for proper handling of SHTxx humidity
sensors (Reconditioning Procedure)
Available for download at the Sensirion
humidity sensors download center:
www.sensirion.com/humidity-download
Sensirion Humidity Sensor
Specification Statement
Definition of sensor specifications.
Available for download at the Sensirion
humidity sensors download center:
www.sensirion.com/humidity-download
Table 9 Documents containing further information relevant for theSHT3x-ARP.
Revision History
Date
Version
Page(s)
Changes
0.9
Initial release
0.91
2-4
Added definition for sensitivity
Table 5, removed MM model due to change in AEC Q100 Rev H, amended
absolut maximum ratings
Datasheet SHT3x-ARP
www.sensirion.com May 2015 - Version 0.93 12/13
0.93
8
Section 5, added section paragraph on package standard
Section 8, Added ordering information
Table 2, defined Long term drift as max
Table 3, amended Power-up/down level
Datasheet SHT3x-ARP
www.sensirion.com May 2015 - Version 0.93 13/13
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SENSIRION AG
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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
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phone: +41 44 927 11 66
info@sensirion.com
www.sensirion.com
To find your local representative, please visit
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