Preliminary Data Sheet SHT3x-ARP
Humidity and Temperature Sensor
Fully calibrated, linearized, and temperature
compensated digital 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 SHT3xARP 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 ..................................................... 5
4
Operation and Communication .............................. 5
5
Packaging.............................................................. 7
6
Shipping Package ................................................. 9
7
Quality ................................................................. 10
8
Ordering Information............................................ 10
9
Further Information .............................................. 10
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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.
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Preliminary Data Sheet SHT3x-ARP
1
Sensor Performance
1.1
Humidity Sensor Performance
Parameter
SHT30 Accuracy tolerance1
SHT31 Accuracy tolerance1
Repeatability2
Resolution
Integrated Non-Linearity3
Hysteresis
Specified range4
Response time6
Long-term drift
Conditions
Value
Units
Typ.
Max.
Typ.
Max.
3
Figure 2
2
Figure 4
0.2
14
0.2
0.8
0 to 100
8
2
s
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.
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.
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Preliminary Data Sheet SHT3x-ARP
2
2.1
Specifications
Electrical Specifications
Parameter
Supply voltage
Power-up/down level
Symbol
VDD
VPOR
Supply current
IDD
Output current
AOIOUT
Capacitive load
CL
Duration of reset pulse
Condition
Min
Typ.
Max
2.4
2.22
3.3
2.35
5.5
2.4
Average
tRESETN
V
V
A
217
-100
Units Comments
100
A
5
nF
350
ns
At a measurement rate
of 2 Hz.
Depends on the resistive
load on the output pins
Capacitance that can be
driven by the sensor on
the signal lines
See section 3.3
Table 3 Electrical specifications, Specification are at 25°C and typical VDD
2.2
Timing Specification for the Sensor System
Parameter
Power-up time
Analog output settling time
Symbol
Conditions
tPU
After hard reset,
VDD ≥ VPOR
AOsettle
For a step of VDD/2
Min.
Typ.
Max.
15
0.3
Units Comments
Time between VDD reaching
ms VPOR and first measurement
signal available
Time needed for adapting to a
changing supply voltage and
measurement value. Value
ms
depends on output load.
Typical value is for a load of
1nF.
Table 4 System Timing Specification, Specification are at 25°C and typical VDD
2.3
Absolut 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
Supply voltage VDD
Max Voltage on pins (pin 1 (RH); pin 2
(R); pin 3 (R); pin 4(T); pin 6(nRESET))
Input current on any pin
Operating temperature range
Storage temperature range
ESD HBM (human body model)
ESD MM (machine model)
ESD CDM (charge device model)
Rating
Units
-0.5 to 6
-0.5 to VDD+0.5
V
V
±100
-40 to 125
-40 to 150
4
200
750
mA
°C
°C
kV
V
V
Table 5 Absolut minimum and maximum ratings; values are target specs and not
confirmed by measurements yet
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November 2014 - 0.9
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Preliminary Data Sheet SHT3x-ARP
3
VDD
Pin Assignment
The SHT3x-ARP comes in a tiny 8-pin DFN package –
see Table 6.
Pin
Name
Comments
1
RH
2
R
3
R
4
5
T
VDD
6
nRESET
7
R
8
VSS
Analog voltage out; output
No electrical function; recommended to
connected to VSS
No electrical function; recommended to
connected to VSS
Analog voltage out; output
Supply voltage; input
Reset pin active low; Input; if not used it
is recommended to connect to VDD
No electrical function; recommended to
connected to VSS
Ground
1
8
2
7
3
6
4
5
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, ranging from 10
to 90% of VDD. 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.
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VDD(5)
100nF
T(4)
RH(1)
0.1nF
0.1nF
die
VSS(8) pad R(2,3,7)
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”.
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
nRESET(6)
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 15 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.
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Relative Humidity (%)
Preliminary Data Sheet SHT3x-ARP
100
90
80
70
60
50
40
30
20
10
0
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Voltage out (VRH/VDD)
Figure 8 Relationship between the ratiometric analog voltage output and the measured relative humidity
RH 12.5 125
VRH
10 100 VRH
VDD
0.8 0.8 VDD
251
115
95
201
75
151
55
35
101
15
51
Temperature (°F)
Temperature (°C)
Equation 1 Relative humidity conversion formula (result in %RH):
-5
1
-25
-45
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
-49
100%
Voltage out (VT/VDD)
Figure 9 Relationship between the ratiometric analog voltage output and the measured temperature
T C 66.875 218.75
VT
17.5 175 VT
45
VDD
0.8 0.8 VDD
T F 88.375 393.75
VT
31.5 315 VT
49
VDD
0.8 0.8 VDD
Equation 2 Temperature conversion formula (result in °C and °F respectively)
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Preliminary Data Sheet SHT3x-ARP
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.
5.1
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
dimension of the triangular cut are shown in Figure 11
through the labels T1 & T2.
SHT 3 x
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,
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XYABCD
Figure 10 Top View of the SHT3x-ARP illustrating the
laser marking.
.
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Preliminary Data Sheet SHT3x-ARP
5.2
Package Outline
T1 x T2
b
E
E2
e
S
D
A
L
D2
Figure 11 Dimensional drawing of SHT3x-ARP sensor package
Parameter
Package height
Leadframe height
Pad width
Package width
Center pad length
Package length
Center pad width
Pad pitch
Pad length
Symbol
Min
Nom.
A
A3
0.8
0.9
0.2
1
b
D
D2
E
E2
e
L
S
0.2
2.4
1
2.4
1.7
0.25
2.5
1.1
2.5
1.8
0.5
0.35
0.3
2.6
1.2
2.6
1.9
0.3
Max Units Comments
0.4
1.5
mm
mm
mm
mm
mm
mm
mm
mm
mm
mm
Max cavity
Center pad marking
T1xT2
0.3x45°
mm
Not shown in the drawing
Only as guidance. This value includes all tolerances,
including displacement tolerances. Typically the
opening will be smaller.
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 NonSolder 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.
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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.
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Preliminary Data Sheet SHT3x-ARP
land pattern
stencil aperture
sensor outline
0.25
1.6
0.5
0.4
0.45
0.5
0.375
1.7
0.5
0.375
0.5
0.25
0.5
0.5
0.3x45°
0.3
0.2
0.55
1
0.55
0.75
0.55
0.9
0.8
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
Ø1.5 +.1 /-0.0
4.00
2.00 ±.05 SEE Note 2
0.30 ±.05
Ø1.00 MIN
1.75 ±.1
4.00 SEE Note 1
A
5.50 ±.05
SEE NOTE 2
R 0.2 MAX.
B0
B
12.0 +0.3/-0.1
A
R 0.25 TYP.
K0
A0
SECTION A - A
A0 = 2.75
B0 = 2.75
K0 = 1.20
TOLERANCES - UNLESS
NOTED 1PL ±.2 2PL ±.10
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
DETAIL B
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.
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November 2014 - 0.9
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Preliminary Data Sheet SHT3x-ARP
7
8
Quality
Qualification of the SHT3x-ARP is performed based on
the AEC Q 100 qualification test method.
7.1
This sensor cannot be ordered so far. Samples are
available upon request. Please contact Sensirion.
9
Material Contents
The device is fully RoHS and WEEE compliant, e.g.
free of Pb, Cd, and Hg.
Ordering Information
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,)
SHTxx Design Guide
Design guidelines for designing SHTxx humidity
sensors into applications
SHTxx Handling Instructions
Available for download at the Sensirion
Guidelines for proper handling of SHTxx humidity
humidity sensors download center:
sensors (Reconditioning Procedure)
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
Available for download at the Sensirion
humidity sensors download center:
www.sensirion.com/humidity-download
Available for download at the Sensirion
humidity sensors download center:
www.sensirion.com/humidity-download
Table 8 Documents containing further information relevant for theSHT3x-ARP.
Revision History
Date
Version
0.9
www.sensirion.com
Page(s)
Changes
Initial release
November 2014 - 0.9
10/11
Preliminary Data Sheet SHT3x-ARP
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SENSIRION AG
Laubisruetistr. 50
CH-8712 Staefa ZH
Switzerland
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phone: +1 805 409 4900
info_us@sensirion.com
www.sensirion.com
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phone: +82 31 337 7700 3
info@sensirion.co.kr
www.sensirion.co.kr
phone: +41 44 306 40 00
fax:
+41 44 306 40 30
info@sensirion.com
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Sensirion Japan Co. Ltd.
phone: +81 3 3444 4940
info@sensirion.co.jp
www.sensirion.co.jp
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
http://www.sensirion.com/contact
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