ASP1400 Bidirectional Differential Pressure Meter Ultra low differential pressure from 100 Pa down to 0.002 Pa Zero drift & offset free Outstanding accuracy and resolution Ultra fast response time Fully calibrated & temperature compensated Digital output signal Datasheet April 2008 v2 ASP1400 Product Summary The ASP1400 differential pressure sensor is especially All measurement data is fully calibrated and suited for measurements of ultra low pressure temperature compensated by means of an internal differences of gases and true mass flow micro controller. measurements in bypass solutions. Mounted in rugged, chemically inert PBT housing the The micro-machined silicon sensor element of the ASP1400 is suitable for a wide range of applications. ASP1400 enables extremely long term stable and Such include for example monitoring of clean room offset free measurements. Its leading performance is conditions, intrusion detection and almost unlimited based on SENSIRIONs unsurpassed CMOSens bypass solutions in process control, building control as technology. With CMOSens , the on-chip sensor well as medical applications. element forms an integrated whole with the Bypass solutions allow a true mass flow measurement. amplification and A/D converter circuit. This results in The sensor housing provides two inlets for measuring superior resolution, fast response time and large the differential pressure and withstands overpressures dynamic range at lowest power consumption. of 1 bar (15 psi). The ASP1400 requires a supply voltage of 718Vdc and provides an RS-232 electrical interface. ASP1400 DIFFERENTIAL PRESSURE SENSOR GND Power VOLTAGE GAS FLOW Supply VDD REGULATOR SPI interface /CS CMOSens SENSOR CHIP MICRO SPI MOSI is no longer CONTROLLER Interface MISO supported SCK RS232 LINE RxD RS232 DRIVER/ TxD Interface RECEIVER EEPROM GAS FLOW Figure 1: Block Diagram ASP1400 Differential Pressure Sensor with CMOSens technology www.sensirion.com Sensirion - the sensor company DIFFERENTIAL PRESSURE THERMAL SENSOR AMPLIFIER ADCASP1400 Bidirectional Differential Pressure Meter Introductory Description Combining solid state sensor technology and differential pressure and temperature data are commercial IC fabrication, the ASP1400 dynamic accessed through an RS-232 interface. The RS-232 differential pressure sensor produced by SENSIRION interface allows you to connect the ASP1400 device provides unbeatable performance at very low cost. directly to a PC or PDA using standard terminal The lowest detectable differential pressure is 0.002 software. Pa, which corresponds to a force of only 0.00002g per In general, differential pressures of all gas types can 2 cm or a geographic height difference of only 0.16 be measured using the ASP1400 product. Calibration mm. Covering at the same time a differential pressure is done for dry air. Please contact SENSIRION, if you range of more than 4 orders of magnitude, the would like to use the sensor for applications with other ASP1400 sets a new standard wherever dynamic gases. differential pressure has to be measured or controlled. The ASP1400 device measures the differential (1) (1) pressure with a dynamic principle . The differential Please note that a small gas flow through the pressure induces a small gas flow through a tube of sensor is inherent in the dynamic measurement 1mm diameter. SENSIRIONs unique CMOSens principle. Thus, the ASP1400 is not suitable for technology provides an extremely precise applications where no gas flow is allowed. measurement of this gas flow even for very small differential pressures. In addition, the sensor signal is almost offset free and highly long term stable. You simply connect the gas differential pressure to be CMOSens sensor technology measured to the ASP1400 device to get an CMOSens is the base technology for all Sensirion instantaneous differential pressure at a sampling rate multi sensor modules and sensor systems. The of up to 7Hz (please contact us for sampling rates of unification of semiconductor chip and sensor up to 200Hz). The ASP1400 withstands technology serves as a platform for highly integrated overpressures up to 1 bar without any loss in system solutions with excellent sensor precision and precision. reliability. With CMOSens , the on-chip sensor Please note that absolute pressure (see section 1.4) element forms an integrated whole with the high-end and gas composition have to be well-known to amplification and A/D converter circuit. Due to the achieve measurements of highest accuracy. compact single-chip design, CMOSens based sensors are very resistant to electromagnetic The ASP1400 differential pressure sensor allows an disturbances (EMC), another important technical easy realization of high precision bypass solutions for advantage of this state of the art sensor technology. true mass flow measurements. It has to be pointed As a result, CMOSens based multi sensor modules out that the ASP1400 is based on the successful offer an excellent sensor precision, a fast response ASF1400 mass flow sensor. It measures differential time and a very large dynamic measurement range. In pressure indirectly with the mass flow, which is addition, the digital intelligence of the CMOSens generated through the applied differential pressure. sensor technology enables digital interfaces that Unlike with static differential pressure sensors, you permit an easy link with the system of the customer, a therefore profit in bypass solutions directly from a true real advantage and benefit that results in ready-to-use mass flow measurement. problem solutions (Mount&Sense). In addition to differential pressure, the ASP1400 device also provides information about the temperature on the CMOSens sensor chip. Both www.sensirion.com Datasheet April 2008 v2 2/11