LDE series digital low dierff ential pressure sensors The LDE dieff rential low pressure sensors are based on thermal flow measurement of gas through a micro-flow channel integrated within the sensor chip. The innovative LDE technology features superior sensitivity especially for ultra low pressures. The extremely low gas flow through the sensor ensures high immunity to dust contamination, humidity and long tubing compared to other flow-based pressure sensors. Features Certificates Applications Ultra-low pressure ranges from 25 to 500 Pa Quality Management System according to Medical (0.1 to 2 inH O) EN ISO 13485 and EN ISO 9001 Ventilators 2 Pressure sensor based on thermal micro- RoHS and REACH compliant Spirometers flow measurement CPAP High flow impedance Sleep diagnostic equipment very low flow-through leakage Nebulizers high immunity to dust and humidity Media compatibility Oxygen conservers/concentrators no loss in sensitivity using long tubing Insulff ators/endoscopy Calibrated and temperature compensated Air and other non-corrosive gases Unique offset autozeroing feature ensuring Industrial superb long-term stability HVAC Osff et accuracy better than 0.2% FS VAV Total accuracy better than 0.5% FS typical Filter monitoring On-chip temperature sensor Burner control Analog output and digital SPI interface Fuel cells No position sensitivity Gas leak detection Gas metering Fume hood Instrumentation Security systems E / 11815 / G Subject to change without notice www.first-sensor.com contact first-sensor.com Page 1/13LDE series digital low dierff ential pressure sensors Maximum ratings Parameter Min. Max. Unit Supply voltage V LDE...3... 2.70 3.60 S V DC LDE...6... 4.75 5.25 Output current 1 mA Soldering recommendations (1, 2) Reflow soldering Average preheating temperature gradient 1.5 K/s Time above 217 C 74 s Time above 240 C 30 Peak temperature 245 C Cooling temperature gradient -1.4 K/s Wave soldering, pot temperature 260 C Hand soldering, tip temperature 370 Temperature ranges Compensated 0 +70 Operating -20 +80 C Storage -40 +80 Humidity limits (non-condensing) 97 %RH (3) Vibration 20 g (4) Mechanical shock 500 Pressure sensor characteristics (5) (5) Part no. Operating pressure Proof pressure Burst pressure LDES025U... 0...25 Pa / 0...0.25 mbar (0.1 inH2O) LDES050U... 0...50 Pa / 0...0.5 mbar (0.2 inH2O) LDES100U... 0...100 Pa / 0...1 mbar (0.4 inH O) 2 LDES250U... 0...250 Pa / 0...2.5 mbar (1 inH O) 2 LDES500U... 0...500 Pa / 0...5 mbar (2 inH2O) 2 bar 5 bar (30 psi) (75 psi) LDES025B... 0...25 Pa / 0...0.25 mbar (0.1 inH2O) LDES050B... 0...50 Pa / 0...0.5 mbar (0.2 inH O) 2 LDES100B... 0...100 Pa / 0...1 mbar (0.4 inH O) 2 LDES250B... 0...250 Pa / 0...2.5 mbar (1 inH O) 2 LDES500B... 0...500 Pa / 0...5 mbar (2 inH2O) (6) Gas correction factors Gas type Correction factor Dry air 1.0 Oxygen (O2) 1.07 Nitrogen (N2) 0.97 Argon (Ar) 0.98 Carbon dioxide (CO ) 0.56 2 Specification notes (4) 5 shocks, 3 axes, MIL-STD-883E, Method 2002.4. (1) Recommendations only. Actually reflow settings depend on many factors, for (5) The max. common mode pressure is 5 bar. example, number of oven heating and cooling zones, type of solder paste/flux (6) For example with a LDES500... sensor measuring CO gas, at full-scale output 2 used, board and component size, as well as component density. It is the the actual pressure will be: responsibility of the customer to fine tune their processes for optimal results. P = P x gas correction factor = 500 Pa x 0.56 = 280 Pa eff Sensor (2) Handling instruction: Products are packaged in vacuum sealed moisture P = True differential pressure eff barrier bag with a floor life of 168hours (<30C, 60% R.H.). If floor life or P = Differential pressure as indicated by output signal Sensor environmental conditions have been exceeded prior to reflow assembly, baking is recommended. Recommended bake-out procedure is 72 hours 60C. (3) Sweep 20 to 2000 Hz, 8 min, 4 cycles per axis, MIL-STD-883, Method 2007. E / 11815 / G Subject to change without notice www.first-sensor.com contact first-sensor.com Page 2/13