www.sensirion.com Version 1 – December 2017 1/9
Datasheet SDP3x-Analog
Differential Pressure Sensor with Analog Output
Smallest size enables portable applications
Reflow solderable – Pick & Place
Configurable analog output
Calibrated and temperature compensated
Excellent repeatability, no drift
Product Summary
The SDP3x sensor family is Sensirion’s series of small differential pressure sensors designed for high-volume applications
where size is a key requirement. It builds on the next generation CMOSens® sensor chip that is at the heart of Sensirion’s
new differential pressure and flow sensing platform.
The analog SDP3x sensors offer a calibrated and temperature compensated analog voltage output. The output signal is
configurable: different measurement speeds, output curves and temperature compensations can be selected – even
dynamically during operation mode.
Benefits of Sensirion’s CMOSens® Technology
High reliability and long-term stability
Best signal to noise ratio
Industry-proven technology with a track record of more
than 15 years
Designed for mass production
High process capability
Content
1. Sensor Performance .............................................................. 2
2. Specifications ......................................................................... 3
3. Pin Assignment ...................................................................... 4
4. Package Outline..................................................................... 6
5. Soldering ................................................................................ 7
6. Shipping Package .................................................................. 8
7. Ordering Information .............................................................. 8
Revision History .............................................................................. 8
Important Notices ........................................................................... 9
Headquarters and Subsidiaries ...................................................... 9
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1. Sensor Performance
1.1 Differential Pressure Specification
1
1
Unless otherwise noted, all sensor specifications are valid at 25°C with VDD = 3.3 V and absolute pressure = 966 mbar.
2
For other pressure ranges contact Sensirion
3
Includes repeatability
4
Total accuracy/repeatability is a sum of zero-point and span accuracy/repeatability.
5
Output voltage integral non linearity and output voltage noise are not included and defined later in chapter 2.1. Note that the effect of output voltage
integral non linearity and output voltage noise on accuracy is highly dependent on the output configuration (linear or square root).
Parameter
Configuration
SDP36
SDP37
Measurement range 2
Linear
- 50 to 500 Pa
(-0.2 to 2 inH2O)
- 12.5 to 125 Pa
(-0.05 to 0.5 inH2O)
Square Root
- 500 to 500 Pa
(- 2 to 2 inH2O)
- 125 to 125 Pa
(- 0.5 to 0.5 inH2O)
Zero point accuracy 3,4,5
0.1 Pa 5
0.08 Pa 5
Span accuracy 3,4,5
3% of reading 5
3% of reading 5
Zero point repeatability 4,5
0.03 Pa 5
0.025 Pa 5
Span repeatability 4,5
0.5% of reading 5
0.5% of reading 5
Span shift due to temperature
variation
< 0.5% of reading per 10°C
< 0.5% of reading per 10°C
Offset stability
< 0.01 Pa/year
< 0.01 Pa/year
Response time (τ63)
Slow
< 9 ms
Fast
< 5 ms
Internal digital resolution
16 bit
Calibrated for
Air, N2
Media compatibility
Air, N2, O2, non-condensing
Calibrated temperature range
-40 °C to +85 °C
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2. Specifications
2.1 Electrical Specifications
Parameter
Symbol
Condition
Min.
Typ.
Max.
Units
Comments
Supply
Supply Voltage
VDD
2.7
3.3
5.5
V
Power-up/down level
VPOR
2.3
2.5
2.7
V
Supply current
IDD
3.8
5.5
mA
Ratiometric analog voltage output
Output range
10%
90%
VDD
Resistive load to GND
10 1
100
kOhm
Resistive load to VDD
1000
kOhm
Capacitive load
Cload
100
nF
Output voltage Integral
Non Linearity (INL)
5
mV
Output voltage noise
(RMS)
0.5
mV
2.2 Timing Specifications
Parameter
Symbol
Condition
Min.
Typ.
Max.
Units
Comments
Power-up time
tPU
25
ms
Time to first reliable
measurement
2.3 Mechanical Specifications
Parameter
Symbol
Condition
Min.
Typ.
Max.
Units
Comments
Allowable overpressure2
Pmax
1
bar
Rated burst pressure
Pburst
3
bar
Weight
W
0.2
g
2.4 Materials
Parameter
Wetted materials
glass (silicon nitride, silicon oxide), LCP, green epoxy-based mold compound, epoxy-based resins
REACH, RoHS
REACH and RoHS compliant
2.5 Absolute Maximum Ratings
Parameter
Rating
Units
Supply Voltage VDD
-0.3 to 5.5
V
Max Voltage on pins (Inputs)
-0.3 to VDD+0.3
V
Input current on any pin
±70
mA
Operating temperature range3
-40 to +85
°C
Storage temperature range4
-40 to +85
°C
Max. humidity for long term exposure
40°C dew point
ESD HBM (human body model)
2
kV
1
For a resistive load to GND less than 100kOhm a 1nF capacitor to GND on the AOUT is recommended
2
Allowable overpressure during operation. Refer to the SDP selection guide for pressure dependency of the measured signal. Fast absolute pressure
changes on both ports can result in dynamic effects on the sensor signal. For higher overpressures or continuous high overpressures contact Sensirion.
3
For Air and N2. Long term exposure to high temperatures and (high concentrations of) O2 can reduce the product lifetime
4
For long term storage in Tape and Reel refer to the SDP3x handling instructions
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3. Pin Assignment
The SDP3x consists of a QFN package with a plastic cap covering the top and providing the pneumatic connections to the
sensor. Table 1 shows the pin assignments of the SDP3x-Analog sensor.
Pin no.
Name
Description
1
GND
Connect to ground
2
GND
Connect to ground
3
GND
Connect to ground
4
BWS
Bandwidth selection input
5
TCS
Temperature compensation selection input
6
GND
Connect to ground
7
VDD
VDD Supply
8
OCS
Output curve selection input
9
AOut
Ratiometric analog voltage output
10
GND
Connect to ground
11
GND
Connect to ground
12-16
-
Reserved. Do not connect
Table 1: SDP3x-Analog pin assignment (bottom view).
3.1 Power Pins (VDD, GND)
The power supply pins must be decoupled with a 100 nF capacitor that shall be placed as close to the sensor as possible.
3.2 OCS: Output Curve Selection Input
Config.
Polarity
Description
Conversion to physical values
AOut[V], VDD[V], Differential Pressure (DP) [Pa]
Linear
Low
(GND)
Analog output is configured as a linear
output. The sensor is not fully bi-
directional in this configuration: -10% full-
scale to 100% full scale.
SDP36
(500Pa)
SDP37
(125Pa)
Square
Root
High
(VDD)
Analog output is a fully bi-directional
output with square root conversion. The
benefits are that the bidirectional output
has a more stable zero point and higher
sensitivity at lower pressures
SDP36
(500Pa)
SDP37
(125Pa)
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3.3 TCS: Temperature Compensation Selection Input
Configuration
Polarity
Description
Temperature
compensation for
mass flow
Low (GND)
In this configuration temperature compensation is optimized for applications where
mass flow measurements in bypass are performed
Temperature
compensation for
differential pressure
High (VDD)
In this configuration the analog output signal is temperature compensated for
differential pressure. This configuration is recommended for applications where real
differential pressure measurements are required.
For more information about temperature compensation for differential pressure sensors, for example volume flow
measurements in bypass, refer to the selection guide in the differential pressure download center on our website.
3.4 BWS: Bandwidth Selection Input
Configuration
Polarity
Description
Fast
Low (GND)
In this configuration the chip will output the differential pressure value on the analog
output with the highest possible bandwidth and lowest latency. This configuration is
recommended to be used in use cases where small changes need to be detected
as quickly as possible.
The response time in this configuration is less than 5ms
Slow
High (VDD)
In this configuration extra averaging is in place in order to achieve an excellent
signal to noise ratio.
The response time in this configuration is less than 9ms
3.5 AOut Pin
The AOut pin gives out an analog ratiometric voltage, representing the measured differential pressure value. Please note the
resistive and capacitive loads as mentioned in section 2.1.
Formulas for converting AOut [V] to differential pressure [Pa] can be found in section 3.2.
3.6 Die Pad (Center Pad)
The die pad or center pad is visible from below and located in the center of the package. It is internally connected to GND and
therefore there are no electrical constraints on connecting or not connecting the die pad to GND. For mechanical stability it is
recommended to solder the center pad to the PCB.
The hole in the middle of the die pad must stay open during and after soldering.
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5. Soldering
Recommended land pattern
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 land pattern as a Non- Solder Mask Defined (NSMD) type.
Recommended stencil aperture
The sensor must enter the reflow process only once and with a minimal temperature and exposure time. When both sides of
the PCB are reflow soldered or multiple reflow runs are required, the sensor must be soldered in the last soldering run. In any
case the temperature should not exceed 260°C; temperatures above 200°C should be limited in time to a maximum of 150
seconds.
Ensure that the ports of the sensor are well protected during assembly and soldering so that no dust, solder flux or other
liquids can enter the flow channel. In no case, a board wash shall be applied. It is strongly recommended to use “no-clean”
solder paste.
It is important to note that the diced edge or side faces of the I/O pads may oxidize over time, therefore a solder fillet may or
may not form. Hence there is no guarantee for solder joint fillet heights of any kind.
Refer to the SDP3x handling instructions on our website for more details.
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6. Shipping Package
SDP3x are provided in tape & reel shipment packaging. Standard packaging size is 1500 or 250 units per reel. The drawing of
the packaging tapes with sensor orientation is shown in Figure 2.
Figure 2: Packaging tape and sensor orientation. Header tape is to the right and trailer tape to the left on this drawing
7. Ordering Information
Use the part names and product numbers shown in the following table when ordering SDP3x differential pressure sensor. For
the latest product information and local distributors, visit www.sensirion.com.
Part name
Description / Output
Product number
Packaging
Tape & Reel size
SDP36
Analog, 500Pa
1-101471-02
Tape & Reel (QFN Quad 2 configuration)
1500
1-101571-02
Tape & Reel (QFN Quad 2 configuration)
250
SDP37
Analog, 125Pa
1-101497-02
Tape & Reel (QFN Quad 2 configuration)
1500
1-101572-02
Tape & Reel (QFN Quad 2 configuration)
250
Revision History
Date
Author
Version
Changes
14.12.2017
ANB
V1
Released. Chip revision update. Product numbers updated. Voltage
range extended. Operating temperature extended. TCS now
available.
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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 (including death). 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 datasheet 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 “Handling Instructions” 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 datasheet 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 © 2016-2017, SENSIRION.
CMOSens® is a trademark of Sensirion
All rights reserved
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Switzerland
phone: +41 44 306 40 00
fax: +41 44 306 40 30
info@sensirion.com
www.sensirion.com
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phone: +1 312 690 5858
info-us@sensirion.com
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phone: +82 31 337 7700~3
info-kr@sensirion.com
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phone: +81 3 3444 4940
info-jp@sensirion.com
www.sensirion.co.jp
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phone: +86 755 8252 1501
info-cn@sensirion.com
www.sensirion.com.cn
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phone: +886 3 5506701
info@sensirion.com
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