Datasheet SDP1108-R Low Differential Pressure Sensor with fast response time For medical ventilators (ICU and home care) High sensitivity below 10 Pa to measure small volume flow (neonatal) Fast response time for efficient trigger function Unsurpassed performance thanks to CMOSens technology Offset and hysteresis free Fully calibrated and temperature compensated Not sensitive to the mounting orientation and vibrations SDP1108-R Product Summary superior accuracy, outstanding resolution (up to 0.05 Pa), The SDP1108-R sensor is a differential pressure sensor and lowest temperature dependence. for air based on the successful SDP1000 sensor from Sensirion. The response time of the SDP1108-R has Its leading performance is based on Sensirions proprietary been optimized for medical ventilation applications. CMOSens sensor technology which combines the sensor element with amplification and A/D conversion on one Mounted in a rugged, chemically inert PPS housing the single silicon chip. The differential pressure is measured by SDP1108-R differential pressure sensors feature a unique a thermal sensing element. In contrast to other thermal dynamic range, zero offset and unsurpassed long term differential pressure sensors only a very small amount of stability. This makes it an ideal fit for demanding yet cost air is required. This leads to a reliable operation even sensitive OEM applications in medical and HVAC under harsh conditions. In comparison to membrane and equipment. piezo-resistive based sensors the SDP1108-R differential The SDP1108-R is supplied with 5.0 V and provides a pressure sensors show an extended measurement range, 0.254.0 V output. Although the output of the sensor is better offset stability and improved reproducibility even at analog, the internal linearization and temperature lowest pressure ranges. In addition the SDP1108-R is compensation is performed digitally. This results in a robust against pressure bursts and shows no sensitivity to the mounting orientation. Applications Block Diagram Medical applications: Homecare ventilation Pin 3: OUT CMOSens 0.25 V to 4 V Intensive care ventilation (ICU) SENSOR CHIP Pin 2: GND Pin 1: VDD 5.0 V www.sensirion.com Version 2.1 November 2016 1/7 Differential pressure Sensor A/D converter DIGITAL Linearization and Temperature compensation D/A Memory converter 1 1 Sensor Output Characteristics SDP1108-R 3.75 The SDP1108-R provides a fully calibrated voltage output. To enhance the sensitivity at very low 3.25 differential pressures, the SDP1108-R comes with a 2.75 root-square output characteristic. 2.25 1.75 1.25 0.75 0.25 0 20 40 60 80 100 differential pressure % FS 2 Output Voltage 0.25V Use this formula to convert the sensor output into Diff. Press. Pa 500 physical value. 3.75V 1 Calibration conditions apply unless otherwise noted: 23C and pabsolute = 966 mbar, dry air, VDD = 5.000 V. 2 Specifications 1 Table 1: SDP1108-R Sensor specifications SDP1108-R Unit Parameter Min Typ Max 0.25 - 4 Volts Measurement range 0 - 500 Pa 0 - 2 Inch water 4 20% FS to 100% FS - 1.0 2.0 % Measured Value 5 0 to 20% FS - 0.2 0.4 % Full Span 3 Accuracy 15 40 mV 2 zero - 0.01 0.06 Pa 100 to 500 Pa - 0.3 1.0 % Measured Value Repeatability 5 0 to 100 Pa - 0.05 0.2 % Full Span 6 Null drift per year - 0 0.1 Pa / year 4 0 to 100 % FS - 0.03 0.05 % Measured Value / C Additional error over 7 temperature (T 23C) zero - 1 2 mV/C (8) Response time 6.6 8.0 10.1 ms Cut off frequency of internal filter 17 20 24 Hz 1 Calibration conditions apply unless otherwise noted: 23C and pabsolute = 966 mbar, dry air, VDD = 5.000 V 2 Variance between the zero point (offset) of different sensors measured under the same conditions (e.g. same supply voltage, temperature, ) 3 Include deviations due to linearity, hysteresis, and repeatability 4 % Measured value = (SDP1108-R output Pa - output of reference instrument Pa ) / output of reference instrument Pa . 5 Full span is defined as 3750 mV / 500 Pa for SDP1108-R 6 Drift over time due to aging, pressure cycles Test results can be provided. 7 The additional error due to temperature variation is temporary. Once the sensor is back to the calibration temperature, the shift disappears (no hysteresis). 8 Tau= 0 to 63%, filter response time = 8ms. www.sensirion.com Version 2.1- August 2016 2/7 output voltage V