Preliminary Data Sheet SHT3x-DIS
Humidity and Temperature Sensor
Fully calibrated, linearized, and temperature
compensated digital output
Wide supply voltage range, from 2.4 to 5.5 V
I2C Interface with communication speeds up to 1
MHz and two user selectable addresses
Typical accuracy of 2%RH and 0.3°C
Very fast start-up and measurement time
Tiny 8-Pin DFN package
Product Summary
SHT3x-DIS 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-DIS
has increased intelligence, reliability and improved
accuracy specifications compared to its predecessor. Its
functionality includes enhanced signal processing, two
distinctive and user selectable I2C addresses and
communication speeds of up to 1 MHz. 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-DIS 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-DIS 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
nRESET
RH Sensor T Sensor
ADC
ADC
VDD
Power on
Reset
VSS
Calibration
Memory
Content
1
Sensor Performance.............................................2
2
Specifications .......................................................4
3
Pin Assignment ....................................................6
4
Operation and Communication .............................7
5
Packaging...........................................................13
6
Shipping Package ..............................................15
7
Quality ................................................................16
8
Ordering Information...........................................16
9
Further Information .............................................16
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Data processing
& Linearization
Digital Interface
ADDR
SDA SCL
RESET
Alert Logic
Alert
Figure 1 Functional block diagram of the SHT3x-DIS. 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-DIS
1
Sensor Performance
1.1
Humidity Sensor Performance
Parameter
SHT30 Accuracy tolerance1
SHT31 Accuracy tolerance1
Repeatability2
Resolution
Hysteresis
Specified range3
Response time5
Long-term drift
Conditions
Value
Units
Typ.
Max.
Typ.
Max.
3
Figure 2
2
Figure 4
0.13
0.05
0.8
0 to 100
86
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-DIS.
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-DIS
2
2.1
Specifications
Electrical Specifications
Parameter
Supply voltage
Power-up/down level
Supply current
Heater power
Symbol
Condition
VDD
VPOR
IDD
PHeater
Min.
Typ.
Max.
2.4
2.22
3.3
2.35
5.5
2.4
Not measuring
0.2
Measuring
800
Average
2
Heater running
Units Comments
V
V
Average current when
sensor is not performing
a measurement.
Average current
consumption while
A
sensor is measuring at
lowest repeatability,
Average current
consumption (operation
A with one measurement
per second at lowest
repeatability)
Depending on the
mW
supply voltage
A
5
25
Table 3 Electrical specifications, Specification are at 25°C and typical VDD
2.2
Timing Specification for the Sensor System
Parameter
Symbol
Conditions
Power-up time
tPU
Soft reset time
tSR
Typ.
Max.
After hard reset,
VDD ≥ VPOR
0.3
0.5
After soft reset.
0.3
0.5
tMEAS,l
2.5
3
tMEAS,m
4.5
5
tMEAS,h
12.5
13.5
Duration of reset pulse
Measurement duration
Min.
350
Units Comments
Time between VDD reaching
ms VPOR and sensor entering idle
state
Time between ACK of soft
ms reset command and sensor
entering idle state
ns See section 3.6
Duration for a humidity and
temperature measurement
ms
when the repeatability is set to
low
Duration for a humidity and
temperature measurement
ms
when the repeatability is set to
medium
Duration for a humidity and
temperature measurement
ms
when the repeatability is set to
high
Table 4 System Timing Specification, Specification are at 25°C and typical VDD
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Preliminary Data Sheet SHT3x-DIS
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 (SDA); pin 2
(ADDR); pin 3 (ALERT); pin 4(SCL); 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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Preliminary Data Sheet SHT3x-DIS
3
Pin Assignment
The SHT3x-DIS comes in a tiny 8-pin DFN package –
see Table 6.
Name
Comments
1
SDA
2
ADDR
3
ALERT
4
5
SCL
VDD
6
nRESET
7
R
8
VSS
Serial data; input / output
Address pin; input; connect to either
VDD or VSS, do not leave floating
Indicates alarm condition; output; must
be left floating if unused
Serial clock; input / 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)
Serial Clock and Serial Data (SCL, SDA)
SCL is used to synchronize the communication between
microcontroller and the sensor. The clock frequency can
be freely chosen between 0 to 1000 kHz. Commands
with clock stretching according to I2C Standard9 are
supported.
The SDA pin is used to transfer data to and from the
sensor. For safe communication, the timing
specifications defined in the I2C manual9 must be met.
Both SCL and SDA lines are open-drain I/Os with diodes
to VDD and VSS. They should be connected to external
pull-up resistors (please refer to Figure 7). A device on
the I2C bus must only drive a line to ground. The external
pull-up resistors (e.g. Rp=10 kΩ) are required to pull the
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VDD(5)
ALERT(3)
SCL(4)
ADDR(2)
SDA(1)
die
VSS(8) pad
3.3
The electrical specifications of the SHT3x-DIS 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
nRESET(6)
RP
RP
R(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.
Table 6 SHT3x-DIS pin assignment (Transparent top view).
Dashed lines are only visible if viewed from below. The die
pad is internally connected to VSS.
3.1
VDD
100nF
Pin
signal high. For dimensioning resistor sizes please take
bus capacity and communication frequency into account
(see for example Section 7.1 of NXPs I2C Manual for
more details9). It should be noted that pull-up resistors
may be included in I/O circuits of microcontrollers. It is
recommended to wire the sensor according to the
application circuit as shown in Figure 7.
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”.
3.4
ADDR Pin
Through the appropriate wiring of the ADDR pin the I2C
address can be selected. Please note that the I2C
address is represented through the 7 MSBs of the I2C
read or write header. The LSB switches between read or
write header. The wiring for the default address is shown
in Table 7 and Figure 7. The ADDR pin must not be left
floating. Please note that only the 7 MSBs of the I2C
Read/Write Header constitute the I2C Address.
SHT3x-DIS
I2C Address in Hex.
representation
I2C address A
0x44 (default)
I2C address B
0x45
Condition
ADDR (pin 2)
connected to VSS
ADDR (pin 2)
connected to VDD
Table 7 I2C device address
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Preliminary Data Sheet SHT3x-DIS
3.5
ALERT Pin
The alert pin may be used to connect to the interrupt pin
of a microcontroller. The output of the pin depends on
the value of the RH/T reading relative to programmable
limits. Its function is explained in a separate application
note. If not used, this pin must be left floating.
3.6
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. Its function is
explained in more detail in section 4. If not used it is
recommended to connect to VDD.
4
Operation and Communication
The SHT3x-DIS supports I2C fast mode (and
frequencies up to 1000 kHz). Clock stretching can be
enabled and disabled through the appropriate user
command. For detailed information on the I2C protocol,
refer to NXP I2C-bus specification9.
All SHT3x-DIS commands and data are mapped to a 16bit address space. Additionally, data and commands are
protected with a CRC checksum. This increases
communication reliability. The 16 bits commands to the
sensor already include a 3 bit CRC checksum. Data send
from and received by the sensor is always succeeded by
an 8 bit CRC.
In write direction it is mandatory to transmit the
checksum, since the SHT3x-DIS only accepts data if it is
followed by the correct checksum. In read direction it is
up to the master to decide if it wants to read and process
the checksum.
4.1
Power-Up and Communication Start
The sensor starts powering-up after reaching the powerup threshold voltage VPOR specified in Table 3. After
reaching this threshold voltage the sensor needs the
time tPU to enter idle state. Once the idle state is entered
it is ready to receive commands from the master
(microcontroller).
address plus 0 as the write bit) and a 16-bit
measurement command. The proper reception of each
byte is indicated by the sensor. It pulls the SDA pin low
(ACK bit) after the falling edge of the 8th SCL clock to
indicate the reception. A complete measurement cycle is
depicted in Table 8.
With the acknowledgement of the measurement
command, the SHT3x-DIS starts measuring humidity
and temperature.
4.3
Measurement Commands for Single Shot
Data Acquisition Mode
In this mode one issued measurement command
triggers the acquisition of one data pair. Each data pair
consists of one 16 bit temperature and one 16 bit
humidity value (in this order). During transmission the
data pair is always followed by a CRC checksum, see
section 4.4.
In single shot mode different measurement commands
can be selected. The 16 bit commands are shown in
Table 8. They differ with respect to repeatability (low,
medium and high) and clock stretching (enabled or
disabled).
The repeatability setting influences the measurement
duration and the current consumption of the sensor. This
is explained in section 2.2.
During measurement the sensor generally does not
respond to any I2C activity, i.e. I2C read and write
headers are not acknowledged (NACK). However, when
a command with clock stretching has been issued, the
sensor responds to a read header with an ACK and
subsequently pulls down the SCL line. The SCL line is
pulled down until the measurement is complete. As soon
as the measurement is complete, the sensor releases
the SCL line and sends the measurement results.
Each transmission sequence begins with a START
condition (S) and ends with a STOP condition (P) as
described in the I2C-bus specification. The stop
condition is optional. Whenever the sensor is powered
up, but not performing a measurement or
communicating, it automatically enters sleep state for
energy saving. This sleep state cannot be controlled by
the user.
4.2
Starting a Measurement
A measurement communication sequence consists of a
START condition, the I2C write header (7-bit I2C device
9
http://www.nxp.com/documents/user_manual/UM10204.pdf
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Preliminary Data Sheet SHT3x-DIS
Condition
Repeatability
Clock
stretching
Hex. code
MSB
LSB
High
06
Medium
enabled
0x2C
0D
Low
10
High
00
Medium
disabled
0x24
0B
Low
16
e.g. 0x2C06: high repeatability measurement with clock
stretching enabled
In case the user needs humidity and temperature data
but does not want to process CRC data, it is
recommended to read the first two bytes of data with the
CRC byte (without processing the CRC data) and abort
the read transfer after reading the second two data bytes
with a NACK.
4.5
Measurement Commands for Periodic
Data Acquisition Mode
In this mode one issued measurement command yields
a stream of data pairs. Each data pair consists of one 16
bit temperature and one 16 bit humidity value (in this
order).
In periodic mode different measurement commands can
be selected. The corresponding 16 bit commands are
shown in Table 9. They differ with respect to repeatability
(low, medium and high) and data acquisition frequency
(0.5, 1, 2, 4 & 10 measurements per second, mps). Clock
stretching cannot be selected in this mode.
The data acquisition frequency and the repeatability
setting influences the measurement duration and the
current consumption of the sensor. This is explained in
section 2.2 of this datasheet.
Condition
Repeatability
After the sensor has completed the measurement, the
master can read the measurement results (pair of RH&
T) by sending a START condition followed by an I2C
read header. The sensor will acknowledge the reception
of the read header and send two bytes of data
(temperature) followed by one byte CRC checksum and
another two bytes of data (relative humidity) followed by
one byte CRC checksum. Each byte must be
acknowledged by the microcontroller with an ACK
condition for the sensor to continue sending data. If the
sensor does not receive an ACK from the master after
any byte of data, it will not continue sending data.
The sensor will send the temperature value first and then
the relative humidity value. After receiving the checksum
for the humidity value a NACK and stop condition should
be send (see Table 10).
1
S
2
3
4
5
6
I2C Address
I2C write header
7
8
9
W
1
2
3
4
5
6
7
Command MSB
8
9
10 11 12 13 14 15 16 17 18
Command LSB
ACK
Readout of Measurement Results for
Single Shot Mode
ACK
4.4
mps
High
32
Medium
0.5
0x20
24
Low
2F
High
30
Medium
1
0x21
26
Low
2D
High
36
Medium
2
0x22
20
Low
2B
High
34
Medium
4
0x23
22
Low
29
High
37
Medium
10
0x27
21
Low
2A
e.g. 0x2F31: 10 high repeatability mps - measurement per
second
ACK
Table 8 Measurement commands in single shot mode (Clear
blocks are controlled by the microcontroller, grey blocks by
the sensor.)
Hex. code
MSB
LSB
16-bit command
Table 9 Measurement commands for periodic data acquisition
mode (Clear blocks are controlled by the microcontroller, grey
blocks by the sensor.)
The I2C master can abort the read transfer with a NACK
condition after any data byte if it is not interested in
subsequent data, e.g. the CRC byte or the second
measurement result, in order to save time.
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Preliminary Data Sheet SHT3x-DIS
4.6
Readout of Measurement Results for
Periodic Mode
Transmission of the measurement data can be initiated
through the command shown in Table 10. If no
measurement data is present the I2C read header is
responded with a NACK instead of an ACK (Bit 9 in Table
10) and the communication stops.
Command
Hex code
Fetch Data
0x E0 00
4.8
Reset
A system reset of the SHT3x-DIS can be generated
externally by issuing a command (soft reset) or by
sending a pulse to the dedicated reset pin (nReset pin).
Additionally, a system reset is generated internally
during power-up or when brownout conditions are met.
During the reset procedure the sensor will not process
commands.
In order to achieve a full reset of the sensor without
removing the power supply, it is recommended to use the
nRESET pin of the SHT3x-DIS.
Soft Reset
Table 10 Data fetch command (Clear blocks are controlled
by the microcontroller, grey blocks by the sensor.)
4.7
ART Command
The unique ART (accelerated response time) feature
can be activated by issuing the command in Table 12.
The art command is structurally similar to any other
command in Table 9. Hence section 4.5 & 4.6 apply for
starting a measurement and reading out data. The ART
feature can also be evaluated using the Evaluation Kit
EK-H5 from Sensirion.
Command
Hex Code
Periodic Measurement with
ART
0x30A2
4
5
6
I2C Address
7
8
9
W
I2C write header
1
2
3
4
5
6
7
Command MSB
8
9
It is worth noting that the sensor reloads calibration data
prior to every measurement by default.
Command
Hex Code
Soft Reset
0x30A2
Table 12 Soft reset command (Clear blocks are controlled
by the microcontroller, grey blocks by the sensor.)
10 11 12 13 14 15 16 17 18
Command LSB
ACK
3
ACK
S
2
ACK
1
The SHT3x-DIS provides a soft reset mechanism that
forces the system into a well-defined state without
removing the power supply. When the system is in idle
state the soft reset command can be sent to the SHT3xDIS. This triggers the sensor to reset its system
controller and reloads calibration data from the memory.
In order to start the soft reset procedure the command
as shown in Table 12 should be sent.
16-bit command
Table 11 Command for a periodic data acquisition with the
ART feature (Clear blocks are controlled by the
microcontroller, grey blocks by the sensor.)
Reset through the nReset Pin
Pulling the nReset pin low (see Table 6) generates a
reset similar to a hard reset (switching the power supply
to the VDD Pin off and then on again. The pins 1 (SDA),
4(SCL) and 2(ADDR) have a lower voltage than VDD.
Otherwise the sensor will be powered over the ESD
diodes. The reset pin is internally connected to VDD
through a pull-up and hence active low. The nReset pin
has to be pulled low for at least 350 ns to generate a
reset.
General Call
Additionally a reset of the sensor can also be generated
using the “general call” mode according to I2C-bus
specification9. This generates a reset which is
functionally identical to using the nReset pin. It is
important to understand that a reset generated in this
way is not device specific. All devices on the same I2C
bus that support the general call mode will perform a
reset. Additionally, for this command to work it is required
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Preliminary Data Sheet SHT3x-DIS
that the sensor is able to process I2C commands. The
appropriate command consists of two bytes and is
shown in Table 13.
Command
Code
Address byte
Second byte
Reset command using the
general call address
0x00
0x06
3
4
5
6
7
8
S General Call Address
9
General Call 1st byte
1
2
3
4
5
6
7
8
Command
Hex Code
Clear status register
0x 30 41
9
ACK
2
All flags (Bit 15, 11, 10, 4) in the status register can be
cleared (reinitialized to their default value) by sending the
command shown in Table 16.
0x0006
ACK
1
Clear Status Register
Reset Command
General Call 2nd byte
Table 13 Reset through the general call address (Clear
blocks are controlled by the microcontroller, grey blocks by
the sensor.).
Table 16 Command to clear the status register (Clear
blocks are controlled by the microcontroller, grey blocks by
the sensor.)
Bit
4.9
Heater
The heater can be switched on and off by command, see
table below. The status is listed in the status register.
After a reset the heater is disabled (default condition).
Command
Heater Enable
Heater Disabled
14
13
Hex Code
MSB
LSB
0x306
15
D
6
12
11
10
Table 14 Heater command (Clear blocks are controlled by
the microcontroller, grey blocks by the sensor.)
9:5
4
4.10 Status Register
The status register contains information on the
operational status of the heater, the alert mode and on
the execution status of the last command and the last
write sequence. The command to read out the status
register is shown in Table 15 whereas a description of
the content can be found in Table 17.
Command
Hex code
Read Out of status register
0xF32D
3:2
1
0
Field description
Alert pending status
'0': no pending alerts
'1': at least one pending alert
Write '1' to clear all alert flags
Reserved
Heater status
‘0’ : Heater OFF
‘1’ : Heater ON
Reserved
RH tracking alert
‘0’ : no alert
‘1’ . alert
T tracking alert
‘0’ : no alert
‘1’ . alert
Reserved
System reset detected
'0': no reset detected since last ‘clear all
alert flags write’
'1': reset detected (hard reset, soft reset
command or supply fail)
Reserved
Command status
'0': last command executed successfully
'1': last command not processed. It was
either invalid, failed the integrated
command checksum
Write data checksum status
'0': checksum of last write transfer was
correct
'1': checksum of last write transfer failed
Reset
value
‘0’
‘0’
‘0’
‘0’
‘0
‘0’
‘00000’
‘0’
‘00’
‘0’
‘0’
Table 17 Description of the status register
Table 15 Command to read out the status register (Clear
blocks are controlled by the microcontroller, grey blocks by
the sensor.)
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Preliminary Data Sheet SHT3x-DIS
4.11 Checksum Calculation
The 8-bit CRC checksum transmitted after each data
word is generated by a CRC algorithm. Its properties are
displayed in Table 18. The CRC covers the contents of
the two previously transmitted data bytes. To calculate
the checksum only these two previously transmitted data
bytes are used.
Property
Value
Name
Width
Protected data
Polynomial
Initialization
Reflect input
Reflect output
Final XOR
Examples
CRC-8
8 bit
read and/or write data
0x31 (x8 + x5 + x4 + 1)
0xFF
False
False
0x00
CRC (0xBEEF) = 0x92
Table 18 I2C CRC properties.
4.12 Conversion of Signal Output
Measurement data is always transferred as 16-bit values
(unsigned integer). These values are already linearized
and compensated for temperature and supply voltage
effects. Converting those raw values into a physical
scale can be achieved using the following formulas.
Relative humidity conversion formula (result in %RH):
RH 100
S RH
2 16 1
Temperature conversion formula (result in °C & °F):
ST
2 1
S
T F 49 347 16 T
2 1
T C 45 175
16
SRH and ST denote the raw sensor output for humidity
and temperature, respectively. The formulas only work
correct when SRH and ST are used in decimal
representation.
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Preliminary Data Sheet SHT3x-DIS
4.13 Communication Timing
Parameter
Symbol
SCL clock frequency
Hold time (repeated) START
condition
LOW period of the SCL
clock
HIGH period of the SCL
clock
SDA hold time
SDA set-up time
SCL/SDA rise time
SCL/SDA fall time
SDA valid time
Set-up time for a repeated
START condition
Set-up time for STOP
condition
Capacitive load on bus line
Low level input voltage
High level input voltage
Low level output voltage
fSCL
Conditions
Min.
Typ.
0
tHD;STA
After this period, the first
clock pulse is generated
Max.
Units
1000
kHz
0.24
µs
tLOW
0.65
µs
tHIGH
0.26
µs
tHD;DAT
tSU;DAT
tR
tF
tVD;DAT
250
100
ns
ns
ns
ns
µs
tSU;STA
0.6
µs
tSU;STO
0.6
µs
CB
VIL
VIH
VOL
300
300
0.9
400
0.3xVDD
1xVDD
0.66
-0.5
0.7xVDD
3 mA sink current
Comments
pF
V
V
V
Table 19 Communication timing specifications for I2C fm (fast mode), Specification are at 25°C and typical VDD . The numbers above
are values according to the I2C Specification (UM10204, Rev. 5, October 9 13, 2012)
1/fSCL
tHIGH
tR
tLOW
tF
70%
SCL
tSU;DAT
30%
tHD;DAT
DATA IN
70%
SDA
30%
tVD;DAT
tF
DATA OUT
tR
70%
SDA
30%
Figure 8 Timing diagram for digital input/output pads. SDA directions are seen from the sensor. Bold SDA lines are
controlled by the sensor, plain SDA lines are controlled by the micro-controller. Note that SDA valid read time is triggered
by falling edge of preceding toggle.
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Preliminary Data Sheet SHT3x-DIS
5
Packaging
SHT3x-DIS 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 10
through the labels T1 & T2.
SHT 3 x
Traceability
All SHT3x-DIS 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 (=DI) describe the output mode. The third letter (A)
represents the manufacturing year (4 = 2014, 5 = 2015,
www.sensirion.com
XYABCD
Figure 9 Top View of the SHT3x-DIS illustrating the laser
marking.
November 2014 - 0.9
13/17
Preliminary Data Sheet SHT3x-DIS
5.2
Package Outline
T1 x T2
b
E
E2
e
S
D
A
L
D2
Figure 10 Dimensional drawing of SHT3x-DIS 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 20 Package outline
5.3
Land Pattern
Figure 11 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.
www.sensirion.com
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.
November 2014 - 0.9
14/17
Preliminary Data Sheet SHT3x-DIS
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 11 Recommended metal land pattern and stencil apertures for the SHT3x-DIS. 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
Ø1.00 MIN
1.75 ±.1
4.00 SEE Note 1
0.30 ±.05
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 12 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.
www.sensirion.com
November 2014 - 0.9
15/17
Preliminary Data Sheet SHT3x-DIS
7
8
Quality
Qualification of the SHT3x-DIS 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-DIS 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
Available for download at the Sensirion
humidity sensors download center:
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.
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 21 Documents containing further information relevant for theSHT3x-DIS.
Revision History
Date
Version
0.9
www.sensirion.com
Page(s)
Changes
Initial release
November 2014 - 0.9
16/17
Preliminary Data Sheet SHT3x-DIS
Headquarters and Subsidiaries
SENSIRION AG
Laubisruetistr. 50
CH-8712 Staefa ZH
Switzerland
Sensirion Inc., USA
phone: +1 805 409 4900
info_us@sensirion.com
www.sensirion.com
Sensirion Korea Co. Ltd.
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
http://www.sensirion.com
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
www.sensirion.com
November 2014 - 0.9
17/17
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