SLP004D Low pressure sensors FEATURES GENERAL DESCRIPTION · 0...4 "H2O · Accurate low pressure readings · Low cost · High impedance bridge · Low noise · Low power consumption for battery operation The SLP series of pressure sensors provides low cost measuring for very low pressures. These devices were specifically designed to accurately measure differential and gage pressures of 0 to 4 "H2O. They are compatible for use with non-corrosive and non-ionic media, such as air and dry gases. The devices allow application of pressure to either side of the diaphragm and can be used for gage or differential pressure measurements. APPLICATIONS · Medical instrumentation · Portable and battery powered equipment · Air flow monitoring · HVAC · Industrial controls EQUIVALENT CIRCUIT Scale: 1 cm ½ inch ELECTRICAL CONNECTION DIFFERENTIAL/GAGE Vs + OUTPUT+ output +VS GROUND OUTPUT- +VS - Note: Polarity applies for positive pressure applied to port P2 (backward gage) July 2005 / 046 BUTTON PACKAGE "D4" DIP PACKAGE 1/4 www.sensortechnics.com SLP004D Low pressure sensors ABSOLUTE MAXIMUM RATINGS Supply voltage, VS Temperature range Operating Storage Common-mode pressure Lead temperature (soldering 4 sec.) Proof pressure Burst pressure1 7.5 VDC 0 to 50°C 0 to 70°C 150 "H2O 250°C 10 "H2O 5 psi or 150 "H2O SLP004D PERFORMANCE CHARACTERISTICS1 Characteristics Min. Typ. Max. Unit Operating pressure Sensitivity TA= 25°C Full-scale span 4 "H2O2 Temperature coefficient of span5,8 Zero pressure offset TA= 25°C Temperature coefficient of offset5 Combined linearity and hysteresis3 Long term stability of offset and sensitivity7 Response time (10 % to 90 %)6 Input resistance TA = 25°C Temperature coefficient of resistance5,8 Output impedance Repeatability4 Position sensitivity --+1700 +34 -2850 -40 ----------+2100 ------- --+2500 +50 -2400 0 ±4 0.5 0.5 0.5 4.65 +2300 4.70 0.2 50 4 +5500 +110 -1950 +40 --1.0 ------+2500 ------- "H2O µV/V/"H2O mV ppm/°C mV µV/V°C %FS %FS ms kΩ ppm/°C kΩ %FS µV/V/g WARNING: Due to the delicate nature of these very sensitive devices, some special handling is required . Parts are sensitive to shock and vibration and must be handled with care. Dropping on any hard surface (bench top etc.) can destroy the device. Note 10 "H2O overpressure. Specification notes: 1. Reference conditions: supply voltage, VS = 5 VDC, TA = 25°C, common-mode line pressure = 0 psig, pressure applied to P2. 2. Span is the algebraic difference between the output voltage at full scale pressure and the output at zero pressure. 3. See Definition of Terms: Hysteresis - the maximum output difference at any point within the operating pressure range for increasing and decreasing pressure. 4. Maximum difference in output at any pressure with the operating pressure range an temperature within 0°C to +50°C after: a) 1,000 temperature cycles, 0°C to 50°C b) 1.5 million pressure cycles, 0 psi to full-scale span 5. Slope of the best straight line from 0°C to 50°C. For operation outside this temperature, contact factory for more specific applications information. 6. Response time for a 0 psi to full-scale span pressure step change. 10 % to 90 % rise time. 7. Long term stability over a one year period. 8. This parameter is is not 100 % tested. It is guaranteed by process design and tested on a sample basis only. 9. If the maximum burst pressure is exceeded, even momentarily, the package may leak or burst, or the pressure sensing die may fracture. 2/4 July 2005 / 046 www.sensortechnics.com SLP004D Low pressure sensors TYPICAL PERFORMANCE CHARACTERISTICS APPLICATION INFORMATION General Information The SLP family of pressure sensors function as a wheatstone bridge. When pressure applied to the device the resistors in the arms of the bridge change as shown in Figure 1. The resulting differential output voltage, V0, is easily shown to by V0 = VB x ∆R. Since the change in resistance is directly proportional to pressure, V0 can be written as: V0 = S x P x VB + VOS where: V0 S P VB VOS is the output voltage in mV is the sensitivity in mV/V psi is the pressure in psi is the bridge voltage in volts is the offset error (the differential output voltage when the applied pressure is zero). For a complete application discussion see SenSym´s SCC series datasheet. Figure I July 2005 / 046 3/4 www.sensortechnics.com SLP004D Low pressure sensors PHYSICAL DIMENSIONS Button package mass: 1 g dimensions in inches (mm) D4-housing 0.550 (13.97) P1 0.050 typ. (1.27) P2 0.470 (11.94) 0.090 typ. (2.29) 0.135 (3.43) 0.300 (7.62) 0.250 (6.35) 0.285 (7.24) 0.070 (1.78) 0.600 (15.24) mass: 1 g 0.01 (0.25) 0.380 (9.65) 0.110 typ. (2.79) 0.020 typ. (0.51) 0.100 typ. (2.54) dimensions in inches (mm) ORDERING INFORMATION Pressure range 0 to 4 "H2O Order part number Button package DIP package SLP004D SLP004DD4 SenSym and Sensortechnics reserve the right to make changes to any products herein. SenSym and Sensortechnics do not assume any liability arising out of the application or use of any product or circuit described herein, neither does it convey any license under its patent rights nor the rights of others. 4/4 July 2005 / 046 www.sensortechnics.com