SDP600 SENSIRION, SDP600 Datasheet - Page 6

• Manufacturer Part Number: SDP600
• Description: Digital Differential Pressure Sensor
• Manufacturer: SENSIRION

Specifications of SDP600

• Sensor Output: Voltage
• Supply Current: 6mA
• External Depth: 18mm
• Voltage Rating: 3.6V
• Port Style: Tube
• Pressure Measurement Type: Differential
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

5. Conversion to Physical Values
The calibrated signal read from the sensor is a signed
INTEGER number (two's complement number). The
INTEGER value can be converted to the physical value by
dividing it by the scale factor (pressure = sensor output
scale factor). The scale factor is specified in Section 2.1.
The SDP600 sensor series features digital temperature
compensation. The temperature is measured on the
CMOSens
data is fed to a compensation circuit that is also integrated
on the CMOSens
compensation is necessary.
A sensor output proportional to mass flow is necessary for
measuring mass flow in a bypass configuration. Even
though the output of the SDP sensors with mass flow
temperature compensation is still differential pressure, the
temperature compensation is adapted especially for mass
flow measurements in a bypass configuration. At
calibration temperature both calibrations are equivalent.
Please find the application note “Measuring Flow in a
Bypass Configuration” on our website
The SDP600 sensor series achieves its unsurpassed
performance by using a dynamic measurement principle.
The applied differential pressure forces a small flow of gas
through the sensor, which is measured by the flow sensor
element. As a result, any variation in gas density affects
the sensor reading. While temperature effects are
compensated
pressure (elevation above sea level) can be compensated
by a correction factor according to the following formula:
DP
DP
P
P
Altitude correction factors:
www.sensirion.com
Altitude
[meters]
cal
amb
5.1
5.2
5.3
5.4
eff
sensor
:
:
250
425
500
750
:
0
: Differential pressure indicated by the sensor
Signal scaling and physical unit
Temperature compensation
Mass flow temperature compensation
Altitude correction
Effective differential pressure
Absolute pressure at calibration (966 mbar)
Actual ambient absolute pressure.
®
chip by an on-chip temperature sensor. This
Ambient pressure (P
[mbar]
DP
internally,
®
eff
sensor chip. No external temperature
= DP
1013
984
966
958
925
sensor
variations
amb
(P
)
cal
Correction factor
(P
/ P
.
cal
amb
/ P
in
)
amb
0.95
0.98
1.00
1.01
1.04
)
atmospheric
Version 1.5 –January 2011
Example: At 750 m above sea level and a sensor reading
of 40 Pa, the effective differential pressure is 41.8 Pa.
Note: In many HVAC applications such as air flow
measurement in a bypass configuration, the described
dependence on absolute pressure is actually welcome
because the quantity that must effectively be controlled is
the mass flow and not the volume flow. Mas flow is
dependent on differential pressure and absolute pressure.
For details please refer to our application note “Measuring
Flow in a Bypass Configuration”.
6. OEM Options
A variety of custom options can potentially be
implemented for high-volume OEM applications. None of
these options is available with the standard sensors.
Contact Sensirion for more information.
A switch version with a programmable trigger level and
programmable hysteresis can be realized.
The sensor temperature can be read out via the digital
interface.
The value of the supply voltage Vdd can be read out via
the digital interface.
Breakage of the sensor element can be detected by a
sensor chip self-test.
For analog voltage output, please contact Sensirion.
6.1
6.2
6.3
6.4
6.5
1500
2250
3000
Switch function
Temperature measurement
Vdd measurement
Broken sensor element detection
Customer-specific interface
842
766
697
1.15
1.26
1.38
6/10