SFM3400-AW Digital Flow Meter for Neonatal/Pediatric Medical Applications
7Pages

Datasheet SFM3400-AW Preliminary Datasheet SFM3400-D Digital Flow Meter for Neonatal/Pediatric Medical Applications      Flow range: ± 33slm (bidirectional) Small dead space < 1ml Re-use (-AW) version Preliminary single-use (-D) version Very fast update time (0.5ms) Product Summary The SFM3400 sensor series is Sensirion’s digital flow meter designed for neonatal/pediatric medical applications. It measures the flow rate of air, oxygen and other nonaggressive gases with superb accuracy. The special design of the flow channel results in a very small dead space. The SFM3400-AW is designed for multiple use with the ability to withstand autoclave procedures. The single-use version SFM3400-D is in development stage with preliminary specifications identical to SFM3400-AW. Therefore, the SFM3400 series is extremely well suited for proximal flow measurements in neonatal/pediatric medical ventilation and other respiratory applications. The SFM3400 series has been designed with the use by medical professionals in mind. It features medical cones for pneumatic connection to standard breathing circuits and a mechanical interface for easy and reliable electrical reconnection. The sensor element, signal processing and digital calibration are on a single microchip assuring very fast signal processing time, best-in-class accuracy and superior robustness to rough handling and adverse conditions. The well-proven and patented CMOSens® sensor technology is perfectly suited for high-quality mass production and is the ideal choice for demanding and costsensitive OEM applications. Sensor chip Proximal flow measurement for infants / neonates Expiratory flow measurement for infants / neonates Ventilation & Anesthesia for infants / neonates Respiratory measurements for infants / neonates Metabolic Measurements for infants / neonates The SFM3400 flow meter features a fifth-generation silicon sensor chip. In addition to a thermal mass flow sensor element, the chip contains an amplifier, A/D converter, EEPROM memory, digital signal processing circuitry, and interface. Due to seamless integration of signal acquisition and processing on the single silicon die significant performance and cost benefits are achieved. OEM options A variety of custom options can be implemented for highvolume OEM applications (custom flow rates, calibration for other gases, different body form factor, disposable option etc.). Contact us for more information.

Reference conditions are temperature = 25°C, absolute pressure = 966 mbar, horizontal flow and Vdd = 5V slm: mass flow measured in liters per minute at standard conditions (T = 20 °C, p = 1013.25 mbar) For "Max" no sensor measured outside of this limit will be shipped and a CpK of 1.33 is targeted For accuracy, noise level or resolution the total value is the sum of the offset and span values This value corresponds to a CpK of 0.67 (95% of sensors within the “Typical” limit) Dependent on tracheal tube diameter % m .v. = % measured value = % of reading Noise level defined as standard...

2. Electrical Specifications2.1 Electrical Characteristics Electrical properties 2.3 Conversion to Physical Values In order to obtain the measured flow in [slm], the measured value needs to be converted using the following formula: measured, value — offset flow flow [slm] = ■ scale factor flow Please note that the first measurement performed directly after chip initialization is not valid. 11 After 4.75V is reached 12 When the heater resistor on the PCB is not in operation 13 16 bit with two least significant bits always zero

3. Mechanical Specifications All dimensions are in millimeters (mm). 3.1 Mechanical fitting Fittings of the SFM3400 sensor correspond to the international standard ISO5356-1:2004. Details about this type of connection can be found in the description of the standard. 3.2 Mechanical / Electrical Interface SFM3400 series has been designed for use in an expiratory environment. Therefore, the sensor has been designed for a connector that can be easily connected and disconnected. The connector itself is not provided as a standard product by Sensirion but Sensirion can help with an application...

ESD information about the additional EEPROM (type: 24LC01BT-I/MC) please consult the datasheet of the EEPROM. Calibration orientation The sensors are calibrated horizontally as depicted in the following graph: Inlet flow conditions In order to provide good flow conditions, the inner diameter of the connecting tube has to be approximately the same as the inner diameter of the SFM3400 main flow channel. Temperature compensation The SFM3400-AW sensor features digital temperature compensation. The temperature is measured on the CMOSens® chip by an on-chip temperature sensor. This data is fed to...

5. Ordering Information Use the part names and product numbers shown in the table below when ordering SFM3400-AW sensors. For the latest product information and local distributors, visit www.sensirion.com.

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 tor any unintended or unauthorized application,...