SENSIRION SDP1000 User manual

www.sensirion.com Sensirion - the sensor company
SDP1000 / SDP2000
Low Range Differential Pressure Sensor
for Air and Non-Aggressive Gases
Data Sheet – v4.0
−For cost sensitive HVAC and medical OEM applications
−Unsurpassed performance thanks to CMOSens®technology
−Offset and hysteresis free
−Excellent accuracy and reproducibility even below 10 Pa
−Fully calibrated and temperature compensated
−Linear or square root extracted output characteristics available
−Not sensitive to the mounting orientation
−Direct PCB mounting with simple snap-on system
SDP1000 / SDP2000 Product Summary
The SDP1000 / SDP2000 differential pressure sensors
for air cover the following measurement ranges: –5 to
125 Pa (0.5 inch H2O), -20 to 500 Pa (2 inch H2O), and -
100 to 3500 Pa (14 inch H2O).
Mounted in a rugged, chemically inert PPS housing the
SDP1000 / SDP2000 differential pressure sensors
feature a unique dynamic range, zero offset and
unsurpassed long term stability. This makes it an ideal fit
for demanding yet cost sensitive OEM applications in
HVAC and medical equipment.
The devices are supplied with 5.0 V and provide a
0.25…4.0 V output. Although the output of the
SDP1000 / SDP2000 differential pressure sensor is
analog, the internal linearization and temperature
compensation is performed digitally. This results in a
superior accuracy, outstanding resolution (up to 0.05
Pa), and lowest temperature dependence. The SDP1000
is available with a linear or square root extracted output
characteristics at the same price. Since fully
exchangeable just a few external electronic components
around the SDP1000 / SDP2000 make a high quality
differential sensor transmitter with e.g. an 0...10 V output
or other interfaces (see Figure 8).
Its leading performance is based on Sensirion’s
proprietary CMOSens®sensor technology which
combines the sensor element with amplification and A/D
conversion on one single silicon chip. The differential
pressure is measured by a thermal sensor element. In
contrast to other thermal differential pressure sensors
only a very small amount of air is required (see
Figure 6). This leads to a reliable operation even under
harsh conditions. In comparison to membrane based
sensors the SDP1000 / SDP2000 differential pressure
sensors show an extended measurement range, better
offset stability and improved reproducibility even at
lowest pressure ranges (see Figure 1 and 2). In addition
the SDP1000 / SDP2000 is robust against pressure
bursts and shows no sensitivity to the mounting
orientation.
SDP1000 / SDP2000 is fully RoHS compliant.
Applications
- Medical
- HVAC
- Automotive
- Process Automation
Block Diagram
Differential
pressure
Sensor
CMOSens®
SENSOR CHIP
DIGITAL
Linearization and
Temperature
compensation
A/D converter
Memory
D/A
converter
VDD
5.0 V
OUT
0.25 V
to 4 V
GND
actual size

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1Specifications
Table 1: Sensor specifications (at 23°C and pabsolute = 966 mbar, VDD = 5.0 V unless otherwise noted).
SDP1000-L025 SDP1000-L05 SDP1000-L SDP1000-R SDP2000-L Unit
Parameter
Min Typ Max Min Typ Max Min Typ Max Min Typ Max Min Typ Max
-62 62 -5 125 - 20 500 - 20 500 -100 3500 Pa
Measurement range
-0.25 0.25 -0.02 0.5 -0.08
2 -0.08 2 -0.4 14 Inch water
Power supply
(see Tab 4) 4.75 5.00 5.25 4.75 5.00 5.25 4.75 5.00 5.25 4.75 5.00 5.25 4.75 5.00 5.25 V
Full scale output
(100 kΩload)
Typ. 4.00V at +62Pa
Typ. 0.20V at –62Pa 4.00 4.00 4.00 4.00 V
Zero Pressure Output 2.10 0.250 0.250 0.250 0.250 V
0.5 0.6 0.2 0.3 0.1 0.2 0.2 0.3 0.1 0.2 % FS
(1)(2)
Accuracy
(also see Figure 1) 1.5 2 1.5 2 1 1.5 1 1.5 1 1.5 % m.v.
(1)
Repeatability 0.3 0.5 0.3 0.5 0.3 0.5 0.3 0.5 0.3 0.5 % m.v.
(1)
Offset stability 0 ±0.1 0
±0.1
0
±0.1 0 ±0.3 0 ±0.3 Pa / year
0.003 0.006 0.003 0.006 0 0 0 0 0 0 % FS/°C
(2) Additional error
over temperature
(T ≠23°C) 0.03 0.05 0.03 0.05 0.03 0.05 0.03 0.05 0.03 0.05 % m.v./°C
Resolution < 30% FS(1) 0.05 0.1 0.2 0.05 0.1 0.2 0.2 0.5 1 Pa
Resolution 30..70% FS(1)
0.2 0.5 1.5 0.2 0.5 1.5 1 2.5 8 Pa
Resolution > 70% FS(1)
0.05 0.1 0.2 0.05 0.1 0.2
1.5 2.2 3 1.5 2.2 3 8 11 14 Pa
(1) FS = full scale or span, m.v. = measured value, i.e. reading, whichever value is bigger
(2) FS = full scale or span, i.e. for the SDP1000 it is 500 Pa (2 “H2O), for the SDP2000 it is 3500 Pa (14 “H2O)
(3) See 2.2 Voltage Output formula for conversion
0
1
2
3
4
5
6
7
8
9
10
0 102030405060708090100
differential pressure [% full scale]
± error [ % of measured value]
0
1
2
3
4
5
6
7
01234
repeatability [Pa]
offset drift/year [Pa]
Figure 1: Accuracy (includes errors caused by offset, linearity,
hysteresis and repeatability) of the SDP1000 -L (1), (2)
compared with typical membrane sensors (3).
Figure 2: Max. repeatability and offset drift/year of
the SDP1000-L (1) compared with two
typical membrane based sensors (2,3).
(1)
(2)
(3)
(1) SDP1000-L
(2,3) Membrane based sensors
1
2
3
(1) SDP1000 / SDP2000 around
23°C
(2) SDP1000 / SDP2000 between
0°…50°C
(3) Typical membrane based
sensor with 1.5% FS error
between 10°…40°C

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Table 2: Additional sensor specifications.
Media Air, N2– for other gases contact Sensirion AG.
Operating Conditions:
- Temperature
- Humidity
-10 °C … +60 °C / 14°F … 140 °F
non-condensing
Ambient storage conditions1 -40 °C … +80 °C / -40°F … 176 °F
Position sensitivity below resolution
Response time 40 ms (for faster response time contact Sensirion)
Admissible overpressure (short term) 1 bar (14.5 PSI)
Burst Pressure Capability 2 bar (29 PSI)
Weight 14 g
Protection Class IP 20
Wetted materials Glass (silicon nitride, silicon oxide), Silicon, PPS (Polyphenylene Sulfide),
PEEK (Polyetheretherketone), FR4, Silicone as static sealing, Epoxy, Gold
Gas flow through sensor see Figure 6.
Lead free The SDP1000 family is fully RoHS compliant
(1) For maximum 2 weeks
1.1 Temperature Compensation
The SDP1000 / SDP2000 differential pressure
sensors feature a sophisticated built-in temperature
compensation circuit. The temperature is measured
on the CMOSens chip by means of a PTAT bandgap
reference temperature sensor. Its data is fed into a
compensation circuit which is also integrated on the
CMOSens®sensor chip. No external temperature
compensation is therefore required.
1.2 Altitude Correction
The SDP1000 / SDP2000 differential pressure
sensors achieve their unsurpassed performance by
using a dynamic measurement principle, i.e. an
applied differential pressure forces a small air flow
through the sensor. This results in a dependence of
the indicated differential pressure on the ambient air
density. While the temperature effect is compensated
(see Paragraph 1.1) the altitude above sea level has
an influence on the SDP1000 / SDP2000 output. If
desired, this effect can be compensated by a
correction factor according to the following equation:
Dpeff = Dpsensor *Pcal / Pamb
where Dpeff is the effective differential pressure,
Dpsensor the differential pressure indicated by the
SDP1000 / SDP2000, Pcal the absolute pressure
during calibration (966 mbar) and Pamb the actual
ambient absolute pressure.
This leads to the following correction factors:
Table 3: Altitude correction factors.
Altitude
[meter]
Ambient Pressure
(Pamb) [mbar]
Correction Factor
Pcal /Pamb
0 1013 0.95
250 984 0.98
425 966 1.00
500 958 1.01
750 925 1.04
1500 842 1.15
2250 766 1.26
3000 697 1.38
Example:
The SDP1000 is used at 750 m above sea level. The
output of the SDP1000 shows 0.5 V, which
corresponds to Dpsensor = 33.3 Pa. Taking into account
the correction factor Pcal / Pamb = 1.04 the effective
differential pressure Dpeff is 33.3 Pa * 1.04 = 34.6 Pa.
Note:
In many HVAC applications such as filter monitoring,
fan/ventilator control or air flow measurement the
described effect is actually welcome since at the end
the mass flow and not volume flow is the effective
value to control.

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2Electrical Specifications
2.1 Power Supply
The SDP1000 / SDP2000 differential pressure
sensors require a stable voltage supply of 5 V.
Influence of the supply voltage variation on the offset
and the sensitivity are given in Table 5.
2.2 Voltage Output
The SDP1000 / SDP2000 features a voltage output
from 0.25 V to 4.0 V (Figure 2, 3). An output voltage
below 0.25 V indicates a negative differential
pressure. This range is not calibrated however.
Exempt from this statement is the SDP1000-L025,
which features a fully bidirectional calibration with 0.2
to 4.0 V output.
The resistive load at the output pin should be larger
than 20 kOhm. The capacitive load at the output pin
must not be larger than 200 pF. If the design shows a
larger capacity at the output pin an additional resistor
is required in series at the output (e.g. 620 Ohm).
Linear output
Formula: P = lfactor * (voltage(1) – 0.250)/3.750
lfactor = SDP1000-L05 SDP1000-L SDP2000-L
Pascal 125 500 3500
Inch water 0.5 2 14
(1) voltage: measured output voltage in Volt.
For bi-directional SDP1000-L025
Formular: P=lfactor * (voltage – 2.10)/1.90
lfactor = 62 Pa or 0.25 Inch water
Square Root output
Formula: P = rfactor * (voltage(1) -0.250)^2
rfactor = SDP1000-R
Pascal 35.55556
Inch water 0.14222
(1) voltage: measured output voltage in Volt.
0.00
1.00
2.00
3.00
4.00
0 20406080100
differential pressure [% full scale]
output voltage [V]
0.00
1.00
2.00
3.00
4.00
0 20406080100
differential pressure [% full scale]
output voltage [V]
Figure 2: Linear output at 5 Vdc supply of the SDP1000-L
and the SDP2000-L. The fine lines indicate the
maximum tolerances including a temperature
variation from 0 to 50°C.
Figure 3: Square root extracted output of the SDP1000-R
and the SDP2000-R at 5 Vdc supply. The fine lines
indicate the maximum tolerances including a
temperature variation from 0 to 50°C.
SDP1000-L / SDP2000-L SDP1000-R / SDP2000-R

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Table 4: SDP1000 / SDP2000 electrical characteristics.
Parameter Conditions Min. Typ. Max. Units
Power Supply Voltage VDD 4.75 5.0 5.25 VDC
Operating Current 5 V, no load, zero flow 4.3 5.2 mA
Output capacitive load Cload 20 200 pF
Recommended load Rload 20 100
∞kΩ
Table 5: Typical power supply dependence of the offset and the sensitivity.
Parameter Device 4.75 V 5.0 V 5.25 V Units
SDP1000-L05 - 0.4 + 0.4
SDP1000-L - 1.6 + 1.6
Offset
SDP2000-L - 10.3 + 10.3
Pa
SDP1000-L05 28 30 32
SDP1000-L 7.1 7.5 7.9
Sensitivity
SDP2000-L 1.01 1.07 1.13
mV/Pa

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3Physical Dimensions and Mounting Information
3.1 Housing
The SDP1000 / SDP2000 differential pressure sensor
is mounted in chemically inert PPS housing. The
rugged package has been designed to withstand
continuous overpressures of at least 1 bar (14.5 PSI).
Burst pressure is > 2 bar (29 PSI)
The physical dimensions and mounting information is
given in Figure 4 and 5.
3.4
(0.134)
5.4
(0.213)
2.54
(0.100)
16.0
(0.630)
44.0
(1.732)
SDP100000206-10033-250-001
Hi Lo
1.8
(0.071)
30.0
(1.181)
Pin# 1 2 3
A
G C
F
D
E
H
I
No Components
inside this Area
B
B
A
Figure 4: Pin out and physical dimensions in mm (inch). The
drawing is not to scale.
Figure 5: SDP1000 / SDP2000 PCB footprint. The
drawing is not to scale.
3.2 Soldering Instructions
The SDP1000 / SDP2000 differential pressure sensor
can be wave soldered. Direct reflow soldering is not
recommended since it may affect the accuracy.
If reflow soldering is required Sensirion recommends
to use an SMD connector (e.g. type Samtec SSM-
103-L-SV) and to mount the SDP1000 / SDP2000
after soldering.
22.1
(0.870)
Dim. [mm] [inch] [mil]
A 3.00 0.118 118
B 3.30 0.130 130
C 1.20 0.047 47
D 10.20 0.402 402
E 28.20 1.110 1110
F 2.54 0.100 100
G 0.60 0.024 24
H 0.50 0.020 20
I 22.70 0.894 894
Pin# Function
1 VDD
(
5Vdc
)
2 Ground
3 OUT (0.25…4 Vdc)
18.3
(0.720)
30.5
(1.200)
5.2
(
0.205
)
13.1
(0.516)

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3.3 Connecting Hose
Sensirion recommends a hose with an inner diameter
of 1/8 to 3/20 inch (3.18 to 3.8mm). Due to the
dynamic measurement principle, a small air flow is
required (Figure 6) which
leads to a dependence on the length of the hose
(Figure 7). Tubes up to 1 m show less than 1 % error
of the measured value (Figure 7).
0
20
40
60
80
100
120
0 20406080100
differential pressure [% full scale]
gas flow [sccm]
Figure 6: Typical air flow through the SDP1000 / SDP2000.
Please note: 1 sccm = 1 cm3/min at 0°C and
1013 mbar pressure (1 sccm = 0.001 norm liter).
Figure 7: Influence of the length of the connecting hose on
the accuracy (using 3/16 inch inner diameter).
Example: a 50 Pa difference pressure is shown as
49.8 Pa when using 0.5 m tube with 3/16 inch
diameter.
4Application Example: A High End Differential Pressure Sensor
Example:
Output Vout : 0…10 Vdc
Range: 0…500 Pa, linear characteristics
Power supply Vsupply: 14.5… 27 Vdc
Component Value
IC1LM78L12
IC2LP2980
SDP SDP1000
OP1, OP2, OP3LMC6044
C1200 nF
C22.2 uF
R110 kΩ(5%, 10 ppm)
R218 kΩ(5%, 10 ppm)
R31 kΩ(5%, 10 ppm)
R4100 Ω
R56 kΩ(3x18 kΩ5%, 10 ppm in
parallel)
R610 kΩ(5%, 10 ppm)
Figure 8: Schematic of a high-end differential pressure transmitter using the SDP1000 / SDP2000. With only a few external
components and no additional calibration the transmitter features an accurate and temperature compensated 0…10 Vdc
output signal. (Component values not valid for SDP1000-L025.)
IC1IC2
Vsupply 5V
+
-
+
- +
-
5V
12V
Vout
SDP1000 / SDP2000
C1C2
C1
R1
R1
R2
R3
R1
R1
R4
R6
R5
OP1
OP2
OP3
Vout = (VSDP – 5V *(R3/(R2+R3))) *(R5+R6)/R5
1
2
3
Length of the
connecting hose
Deviation of
Measured Value
0.5 m (20 inch) - 0.4 %
1.0 m (40 inch) - 0.8 %
2.0 m (80 inch) - 1.6 %
4.0 m (160 inch) - 3.2 %
1
2
3
12V 12V 12V

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5Ordering Information
When ordering SDP1000 / SDP2000 differential pressure sensors please refer to the following part names and article
numbers. For the latest product information and local distributor check out Sensirion’s website on
http://www.sensirion.com
Table 6: Overview ordering information
Part Name Output Range (Full Scale) Article Number
SDP1000-L025 Voltage 0.2 – 4.0 V, linear ± 62 Pa ± 62 mbar ±0.25 "H20 ± 0.009 PSI 1-100313-02
SDP1000-L05 Voltage 0.25 - 4.0 V, linear 125 Pa 1.25 mbar 0.5 "H20 0.018 PSI 1-100235-02
SDP1000-L Voltage 0.25 - 4.0 V, linear 500 Pa 5 mbar 2 "H20 0.07 PSI 1-100110-02
SDP2000-L Voltage 0.25 - 4.0 V, linear 3500 Pa 35 mbar 14 "H20 0.50 PSI 1-100113-02
SDP1000-R Voltage 0.25 - 4.0 V, square root 500 Pa 5 mbar 2 "H20 0.07 PSI 1-100111-02
SDPx000-OEM For high quantity OEM versions (e.g. with digital output), please contact Sensirion. -
6Revision history
Table 7: Revision history
Date Version Page(s) Changes
November 2002 Preliminary v0.9 all First preliminary release
January 2003 First release all Specifications, typos, various small modifications
December 2004 V2.6 all Introduction type L05
Juni 2005 V2.7 all Change of address, adjusted specifications for type L05
March 2006 V2.8 all Introduction of Sensirion USA address, updated disclaimer
March 2006 V2.9 2,6 New Calibration temperature: 23°C. Change of barbs/ports diameter
specification
October 2006 V3.0 1,8,9 RoHS statement, Introduction of revision history in this document
May 2008 V3.1 All RoHS statement on page 3, New disclaimer on page 10, Contact
addresses updated, Various small modifications, Inconsistency in Zero
Pressure / Full Scale Output corrected
September 2008 V4.0 2-5,8 SDP2000-R discontinued, new SDP1000-L025 implemented, power
consumption, power supply dependence and temperature dependence
changed due to new SF04 sensor chip version, article number index
counted up due to new sensor chip version. Small linguistic adaptations.
Notes:

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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 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©2001-2008, SENSIRION.
CMOSens®is a trademark of Sensirion
All rights reserved
RoHS and WEEE Statement
The SDP1000 family complies with requirements of the
following directives:
•EU Directive 2002/96/EC on waste electrical
and electronic equipment (WEEE),
OJ13.02.2003; esp. its Article 6 (1) with Annex
II.
•EU Directive 2002/95/EC on the restriction of
the use of certain hazardous substances in
electricaland electronic equipment (RoHS), OJ
13.02.2003; esp. its Article 4.

www.sensirion.com v4.0 October 2008 10/10
Headquarters and Sales Offices
Sensirion AG Phone: + 41 44 306 40 00
Laubisruetistrasse 50 Fax: + 41 44 306 40 30
CH-8712 Staefa ZH e-mail: [email protected]
Switzerland Web: www.sensirion.com
SENSIRION Inc Phone: [phone]
Westlake Pl. Ctr. I, suite 240 Fax: [phone]
2801 Townsgate Road e-mail: [e-mail]
Westlake Village, CA 91361 Web: www.sensirion.com
USA
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#1414, Anyang Construction Twr B/D Fax: [phone]
1112-1, Bisan-dong, Anyang-city e-mail: [email protected]
Gyeonggi-Province, Web: www.sensirion.co.kr
South Korea
SENSIRION Japan phone: [phone]
Sensirion Japan Co. Ltd. fax: [phone]
Shinagawa Station Bldg. 7F e-mail: [email protected]
4-23-5 Takanawa Web: www.sensirion.co.jp
Minato-ku, Tokyo, Japan