FPS SERIES PRESSURE SENSOR Features • Pressure Ranges from 0.1 to 2 inH2O (25 to 500 Pa) • Pressure Sensor based on thermal micro-flow measurement • Calibrated and Temperature compensated • Analog Output and Digital SPI Interface • High Flow Impedance • Very low flow-through leakage • High immunity to dust and humidity • No loss in sensitivity using long tubing • RoHS and REACH compliant Pressure Sensor Characteristics Device Operating Pressure Proof Pressure5 Burst Pressure5 FPSS025U 0.1 inH2O 0 - 25 Pa 0 - 0.25 mbar 30 psi (2 bar) 30 psi (2 bar) FPSS050U 0.2 inH2O 0 - 50 Pa 0 - 0.50 mbar 30 psi (2 bar) 30 psi (2 bar) FPSS100U 0.4 inH2O 0 - 100 Pa 0 - 1.00 mbar 30 psi (2 bar) 30 psi (2 bar) FPSS250U 1.0 inH2O 0 - 250 Pa 0 - 2.50 mbar 30 psi (2 bar) 30 psi (2 bar) FPSS500U 2.0 inH2O 0 - 500 Pa 0 - 5.00 mbar 30 psi (2 bar) 30 psi (2 bar) FPSS025B ±0.1 inH2O 0 - ±25 Pa 0 - ±0.25 mbar 30 psi (2 bar) 30 psi (2 bar) FPSS050B ±0.2 inH2O 0 - ±50 Pa 0 - ±0.50 mbar 30 psi (2 bar) 30 psi (2 bar) FPSS100B ±0.4 inH2O 0 - ±100 Pa 0 - ±1.00 mbar 30 psi (2 bar) 30 psi (2 bar) FPSS250B ±1.0 inH2O 0 - ±250 Pa 0 - ±2.50 mbar 30 psi (2 bar) 30 psi (2 bar) FPSS500B ±2.0 inH2O 0 - ±500 Pa 0 - ±5.00 mbar 30 psi (2 bar) 30 psi (2 bar) Gas Correction Factors10 (Page 7) Gas Type Dry Air Oxygen (O2) Nitrogen (N2) Argon (Ar) Carbon dioxide (CO2) Electrical Connection Correction Factor 1.00 1.07 0.97 0.98 0.56 All Sensors Pin 1, 10 2 3 4, 5 6 7 8 9 Connection Do Not Connect Vs GND Vout SCLK MOSI MISO /CS Note: Pins 1 and 10 are internally connected. DS-0329 Rev B Page 1 f 408 225 2079 • Air and other non-corrosive gasses p 408 225 4314 Media a 16035 Vineyard Blvd. Morgan Hill, CA 95037 • HVAC • Medical e www.allsensors.com all sensors Applications Specifications Pressure Sensor Maximum Ratings Environmental Specifications Supply Voltage (VS) FPS 3V 2.70 to 3.30 Vdc FPS 5V 4.75 to 5.25 Vdc Output Current 1 mA Lead Specifications Average preheating temperature gradient Soak time Time above 217°C Time above 230°C Time above 250°C Peak Temperature Cooling Temperature gradient 2.5 C/s Approx. 3 min 50 s 40 s 15 s 260°C -3.5 C/s Temperature Ranges Compensated Operating Storage 0°C to 70°C -20°C to 80 °C -40°C to 80 °C Humidity Limits Vibration1 Mechanical Shock2 97% RH (non condensing) 20 g 500 g Specification Notes note 1: Sweep 20 to 2000 Hz, 8 min, 4 cycles per axis, MIL-STD-883, Method 2007. note 2: 5 Shocks, 3 axes, MIL-STD-883E, Method 2002.4. Performance Characteristics4 for: FPSS025x, FPSS050x 5V Device (Vs = 5.0 VDC , TA= 20 °C , PAbs = 1 bara, calibrated in air, output signals analog and digital are non-ratiometric to Vs) Common Characteristics Min Typ Max Units - - ± (1% of reading + 0.5 % FSS) - Total Accuracy 5 to 55°C - - ± (1.5% of reading + 1.5 % FSS) - 0 to 70°C - - ± (3.5% of reading +1.5 %FSS) - - 0.03 - %FSS - - less than noise - - ±0.0002 ±0.0004 inH2O/year Current Consumption (no load) - 7 8 mA Response Time (t63) - 5 - ms Power-On Time - - 25 ms Characteristics Min Typ Max Units Zero Pressure Offset 0.49 0.50 0.51 V Full Scale Span 3.97 4.00 4.03 V - 4.50 - V Offset @ 5 to 55°C - - ±20 mV Offset @ 0 to 70°C - - ±40 mV Span @ 5 to 55°C - ±1.25 ±2 %FSS Span @ 0 to 70°C - ±1.75 ±2.75 %FSS Non-Linearity9 3 Noise Level(RMS) Offset Warm-Up Shift Offset Long Term Stability 6 8 Analog Output (Unidirectional Devices) Full Scale Output Thermal Effects Thermal Effects FPS Series Pressure Sensor Page 2 Performance Characteristics4 (Cont’d) Typ Max Units Zero Pressure Offset 2.49 2.50 2.51 V Full Scale Span 3.97 4.00 4.03 V Output @ Max. Specified Pressure - 4.50 - V Output @ Min. Specified Pressure - 0.50 - V Offset @ 5 to 55°C - - ±15 mV Offset @ 0 to 70°C - - ±30 mV Span @ 5 to 55°C - ±1.25 ±2 %FSS Span @ 0 to 70°C - ±1.75 ±2.75 %FSS Min Typ Max Units Scale Factor (Digital Output)7 0.1 inH2O / ±0.1 inH2O - 300 - counts/0.001 inH2O 0.2 inH2O / ±0.2 inH2O - 150 - counts/0.001 inH2O Zero Pressure Offset Tolerance -0.2 - +0.2 %FSS Full Scale Span Tolerance -0.75 - +0.75 %FSS Offset @ 5 to 55°C - - ±60 counts Offset @ 0 to 70°C - - ±120 counts Span @ 5 to 55°C - ±1 ±1.75 %FSS Span @ 0 to 70°C - ±1.75 ±2.75 %FSS Thermal Effects Characteristics Thermal Effects Thermal Effects p 408 225 4314 Digital Output Performance Characteristics4 for: FPSS100x, FPSS250x, FPSS500x 5V Device (Vs = 5.0 VDC , TA= 20 °C , PAbs = 1 bara, calibrated in air, output signals analog and digital are non-ratiometric to Vs) Common Characteristics Min Typ Max Units - - ± (1% of reading + 0.5 % FSS) - Total Accuracy @ 5 to 55°C - - ± (1.5% of reading + 1.5 % FSS) - @ 0 to 70°C - - ± (3.5% of reading +1.5 %FSS) - 0.03 - %FSS - - less than noise - - - ±0.1 %FSS/year Current Consumption (no load) - 7 8 mA Response Time (t63) - 5 - ms Power-On Time - - 25 ms Non-Linearity 9 3 Noise Level(RMS) Offset Warm-Up Shift Offset Long Term Stability 6 8 All Sensors - DS-0329 Rev B Page 3 a 16035 Vineyard Blvd. Morgan Hill, CA 95037 Thermal Effects e www.allsensors.com Min f 408 225 2079 Characteristics all sensors Analog Output (Bidirectional Devices) Performance Characteristics4 (Cont’d) Analog Output (Unidirectional Devices) Characteristics Min Typ Max Units Zero Pressure Offset 0.49 0.50 0.51 V Full Scale Span 3.97 4.00 4.03 V - 4.50 - V Offset @ 5 to 55°C - - ±10 mV Offset @ 0 to 70°C - - ±12 mV Span @ 5 to 55°C - ±1 ±1.75 %FSS Span @ 0 to 70°C - ±2 ±2.75 %FSS Characteristics Min Typ Max Units Zero Pressure Offset 2.49 2.50 2.51 V Full Scale Span 3.97 4.00 4.03 V Output @ Max. Specified Pressure - 4.50 - V Output @ Min. Specified Pressure - 0.50 - V Offset @ 5 to 55°C - - ±10 mV Offset @ 0 to 70°C - - ±12 mV Span @ 5 to 55°C - ±1 ±1.75 %FSS Span @ 0 to 70°C - ±2 ±2.75 %FSS Full Scale Output Thermal Effects Thermal Effects Analog Output (Bidirectional Devices) Thermal Effects Thermal Effects Digital Output Characteristics Min Typ Max Scale Factor (Digital Output) 0.4 inH2O / ±0.4 inH2O - 75 - counts/0.001 inH2O 1.0 inH2O / ±1.0 inH2O - 30 - counts/0.001 inH2O 2.0 inH2O / ±2.0 inH2O - 15 - counts/0.001 inH2O Zero Pressure Offset Tolerance -0.1 - +0.1 %FSS Full Scale Span Tolerance -0.75 - +0.75 %FSS Offset @ 5 to 55°C - - ±30 counts Offset @ 0 to 70°C - - ±60 counts Span @ 5 to 55°C - ±1 ±1.75 %FSS Span @ 0 to 70°C - ±2 ±2.75 %FSS 7 Thermal Effects Thermal Effects Units FPS Series Pressure Sensor Page 4 Performance Characteristics4 for: FPSS025x, FPSS050x 3V Device (Vs = 3.0 VDC , TA= 20 °C , PAbs = 1 bara, calibrated in air, output signals analog and digital are non-ratiometric to Vs) Min Typ Max Units - - ± (1% of reading + 0.5 % FSS) - Total Accuracy @ 5 to 55°C - - ± (1.5% of reading + 1.5 % FSS) - @ 0 to 70°C - - ± (3.5% of reading +1.5 %FSS) - - 0.03 - Offset Warm-Up Shift - - less than noise - Offset Long Term Stability6 - ±0.0002 ±0.0004 inH2O/year Current Consumption (no load)8 - 14 16 mA Response Time (t63) - 5 - ms Power-On Time - - 25 ms Characteristics Min Typ Max Units Zero Pressure Offset 0.29 0.30 0.31 V Full Scale Span 2.37 2.40 2.43 V - 2.70 - V Offset @ 5 to 55°C - - ±20 mV Offset @ 0 to 70°C - - ±40 mV Span @ 5 to 55°C - ±1.25 ±2 %FSS Span @ 0 to 70°C - ±1.75 ±2.75 %FSS Characteristics Min Typ Max Units Zero Pressure Offset 1.49 1.50 1.51 V Full Scale Span 2.37 2.40 2.43 V Output @ Max. Specified Pressure - 2.70 - V Output @ Min. Specified Pressure - 0.30 - V Offset @ 5 to 55°C - - ±15 mV Offset @ 0 to 70°C - - ±30 mV Span @ 5 to 55°C - ±1.25 ±2 %FSS Span @ 0 to 70°C - ±1.75 ±2.75 %FSS Analog Output (Unidirectional Devices) Full Scale Output Thermal Effects Thermal Effects Analog Output (Bidirectional Devices) Thermal Effects Thermal Effects All Sensors DS-0329 Rev B Page 5 all sensors %FSS e www.allsensors.com Noise Level(RMS) f 408 225 2079 3 p 408 225 4314 Non-Linearity 9 a 16035 Vineyard Blvd. Morgan Hill, CA 95037 Common Characteristics Performance Characteristics4 (Cont’d) Digital Output Characteristics Min Typ Max Scale Factor (Digital Output) 0.1 inH2O / ±0.1 inH2O - 300 - counts/0.001 inH2O 0.2 inH2O / ±0.2 inH2O - 150 - counts/0.001 inH2O Zero Pressure Offset Tolerance -0.2 - +0.2 %FSS Full Scale Span Tolerance -0.75 - +0.75 %FSS Offset @ 5 to 55°C - - ±60 counts Offset @ 0 to 70°C - - ±120 counts Span @ 5 to 55°C - ±1 ±1.75 %FSS Span @ 0 to 70°C - ±1.75 ±2.75 %FSS 7 Thermal Effects Thermal Effects Units Performance Characteristics4 for: FPSS100x, FPSS250x, FPSS500x 3V Device (Vs = 3.0 VDC , TA= 20 °C , PAbs = 1 bara, calibrated in air, output signals analog and digital are non-ratiometric to Vs) Common Characteristics Min Typ Max Units - - ± (1% of reading + 0.5 % FSS) - Total Accuracy 5 to 55°C - - ± (1.5% of reading + 1.5 % FSS) - 0 to 70°C - - ± (3.5% of reading +1.5 %FSS) - - 0.03 - %FSS - - less than noise - - - ±0.1 %FSS/year Current Consumption (no load) - 14 16 mA Response Time (t63) - 5 - ms Power-On Time - - 25 ms Characteristics Min Typ Max Units Zero Pressure Offset 0.29 0.30 0.31 V Full Scale Span 2.37 2.40 2.43 V Non-Linearity 9 3 Noise Level(RMS) Offset Warm-Up Shift Offset Long Term Stability 6 8 Analog Output (Unidirectional Devices) Full Scale Output Thermal Effects Thermal Effects - 2.70 - V Offset @ 5 to 55°C - - ±10 mV Offset @ 0 to 70°C - - ±12 mV Span @ 5 to 55°C - ±1 ±1.75 %FSS Span @ 0 to 70°C - ±2 ±2.75 %FSS FPS Series Pressure Sensor Page 6 Performance Characteristics4 (Cont’d) Max Units Zero Pressure Offset 1.49 1.50 1.51 V Full Scale Span 2.37 2.40 2.43 V Output @ Max. Specified Pressure - 2.70 - V Output @ Min. Specified Pressure - 0.30 - V Offset @ 5 to 55°C - - ±10 mV Offset @ 0 to 70°C - - ±12 mV Span @ 5 to 55°C - ±1 ±1.75 %FSS Span @ 0 to 70°C - ±2 ±2.75 %FSS Min Typ Max Units Scale Factor (Digital Output) 0.4 inH2O / ±0.4 inH2O - 75 - counts/0.001 inH2O 1.0 inH2O / ±1.0 inH2O - 30 - counts/0.001 inH2O 2.0 inH2O / ±2.0 inH2O - 15 - counts/0.001 inH2O Zero Pressure Offset Tolerance -0.1 - +0.1 %FSS Full Scale Span Tolerance -0.75 - +0.75 %FSS Offset @ 5 to 55°C - - ±30 counts Offset @ 0 to 70°C - - ±60 counts Span @ 5 to 55°C - ±1 ±1.75 %FSS Span @ 0 to 70°C - ±2 ±2.75 %FSS Thermal Effects Thermal Effects Digital Output Characteristics 7 Thermal Effects Thermal Effects ΔPeff = ΔPsensor x 14.5 psia Pabs ΔPeff ΔPsensor ΔPabs a 16035 Vineyard Blvd. Morgan Hill, CA 95037 Specification Notes (Cont’d) note 3: Total accuracy is the combined error from offset and span calibration, linearity, pressure hysteresis and temperature effects. note 4: The sensor is calibrated with a common mode pressure of 1 bar absolute. Due to the mass flow based measuring principle, variations in absolute common mode pressure need to be compensated according to the following formula: = True differential pressure = Differential pressure as indicated by output voltage = Current absolute common mode pressure 5: The max. common mode pressure is 30 PSI 6: Figure based on accelerated lifetime test corresponding to 1 year of life. Note 7: The digital output signal is a signed, two’s complement integer. Negative pressures will result in a negative output. Note 8: Please contact All Sensors Corporation for low power options. Note 9: Non-linearity refers to a terminal based FSL (Fitting Straight Line) going through the actual zero pressure reading. Note 10: For example with a FPSS500... sensor measuring CO2 gas, at full-scale output the actual pressure will be 2.00 inH2O x 0.56 = 1.12 inH2O. note note ΔPeff = ΔPsensor x gas correction factor ΔPeff ΔPsensor = True differential pressure = Differential pressure as indicated by output voltage Note 11: For correct operation of FPS 3V devices, the device driving the SPI bus must have a minimum drive capability of ± 2 mA. All Sensors e www.allsensors.com Typ f 408 225 2079 Min p 408 225 4314 Characteristics all sensors Analog Output (Bidirectional Devices) DS-0329 Rev B Page 7 SPI - SERIAL PERIPHERAL INTERFACE Note: It is important to adhere to the communication protocol in order to avoid damage to the Sensor. Introduction Data read The FPS serial interface is a high-speed data input and output communication port that is asynchronous to the internal conversion cycle. The serial interface operates in 3-wire SPI mode. In this setup, the MOSI and MISO pins are tied together, forming a bidirectional data line to the master microcontroller. The remaining serial interface connections consist of chip select (/CS) and serial clock (SCLK). When powered on, the sensor begins to continuously measure pressure. To initiate data transfer from the sensor, the following three unique bytes must be written sequentially, MSB first, to the MOSI pin (see Fig. 1): Step Hexadecimal Binary Description 1 0x2D B00101101 Poll current pressure measurement 2 0x14 B00010100 Send result to data register 3 0x98 B10011000 Read data register Care should be taken to ensure that the sensor is properly connected to the master microcontroller. Refer to the manufacturer's datasheet for more information regarding physical connections. The entire 16 bit content of the FPS register is then read out on the MISO pin, MSB first, by applying 16 successive clock pulses to SCLK with /CS asserted low. Note that the value of the FPS is held at zero for internal signal processing purposes. This is below the noise threshold of the sensor and thus its fixed value does not affect sensor performance and accuracy. Signal control The serial interface is enabled by asserting /CS low. The serial input clock, SCLK, is gated internally to begin accepting the input data at MOSI, or sending the output data on MISO. When /CS rises, the data clocked into MOSI is loaded into an internal register. From the digital sensor output the actual pressure value can be calculated as follows: Note: If SPI communication is not required (i.e. only analog output is being used) pins 6 to 8 must be connected to ground and pin 9 to Vs. Failure to do so may result in damage to the sensor. Pressure [inH2O] = digital output [counts] scale factor counts inH2O So for a 1.0 inH2O sensor (FPSS250B...) with a scale factor of 120 a digital output of 30,000 counts (7530’h) calculates to a positive pressure of 1.0 inH2O. Similarly, a digital output of -30,000 counts (8AD0’h) calculates to a negative pressure of -1.0 inH2O. Fig. 1 : Data Transfer Step 1 Step 2 /CS SCLK (CPOL=0) (CPAH=0) MOSI 0 0 1 0 1 1 0 1 0 0 0 1 0 1 0 0 MISO Step 3 Data from sensor /CS SCLK (CPOL=0) (CPAH=0) MOSI 1 0 0 1 1 0 0 0 MSB MISO 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 FPS Series Pressure Sensor Page 8 Serial Interface Specification Typ. Max. Units MHZ Internal Oscillator Clock Frequency fICLK OSC(4:0)=00000 3.3 4.15 5.3 External Clock Frequency fECLK VCKSEL=0 Min. - 0.2 - - 5 - MHZ 40 - 60 %tECLK %tECLK fECLKIN LO tECLK=1/fECLK External Master Clock Input High Time fECLKIN HI tECLK=1/fECLK 40 - 60 SCLK Setup to Falling Edge /CS tSC - 30 - - ns /CS Falling Edge to SCLK Rising Edge Setup Time tCSS - 30 - - ns /CS Idle Time tCSI fCLK= 4 MHZ 1.5 - - µs SCLK Falling Edge to Data Valid Delay tDO CLOAD=15 pF - - 80 ns Data Valid to SCLK Rising Edge Setup Time tDS - 30 - - ns Data Valid to SCLK Rising Edge Hold Time tDH - 30 - - ns SCLK High Pulse Width tCH - 100 - - ns SCLK Low Pulse Width tCI - 100 - - ns /CS Rising Edge to SCLK Rising Edge Hold Time tCSH - 30 - - ns /CS Falling Edge to Output Enable tDV CLOAD=15 pF - - 25 ns /CS Rising Edge to Output Disable tTR CLOAD=15 pF - - 25 ns FPS (5 V Supply) Maximum Output Load Capacities CLOAD Input Voltage, Logic HIGH VIH Input Voltage, Logic LOW VIL Output Voltage, Logic HIGH VOH Output Voltage, Logic LOW VOL RLOAD= ∞, - 200 - pF Phase Margin > 55 ° RLOAD= ∞, RLOAD= 2 k Ω, RLOAD= ∞, RLOAD= 2 k Ω, 0.8 x Vs Vs-0.1 Vs-0.15 - - 0.2 x Vs 0.5 0.2 V V V V V V RLOAD= 1 k Ω, IO= -20 µA IO=20 µA 0.65 x Vs Vs-0.4 - 15 - 0.35 x Vs 0.4 pF V V V V all sensors Max. External Master Clock Input Low Time e www.allsensors.com MHZ f 408 225 2079 Symbol Conditions Min. p 408 225 4314 Parameter Maximum Output Load Capacities Input Voltage, Logic HIGH Input Voltage, Logic LOW Output Voltage, Logic HIGH Output Voltage, Logic LOW CLOAD VIH VIL VOH VOL Fig. 2 : Timing Diagram tCSI /CS tSC SCLK tDS tCSS tCL tCSH tCH tDH MOSI tDV tDO tTR MISO All Sensors DS-0329 Rev B Page 9 a 16035 Vineyard Blvd. Morgan Hill, CA 95037 FPS (3 V Supply)11 Package Drawings FA01 Package 17.70 12.70 ±0.15 5.60 ±0.2 0.25 High pressure port 10 9 8 7 6 3.0 13.85 15.22 18.03 17.53 10.70 ±0.15 5.0 Ø 2.20 6.26 1 2 3 4 5 1.43 5.08 2.54 3.10 ±0.2 0.51 1.27 1.60 ±0.2 5.60 dimensions in mm 2.50 FA02 Package 17.70 12.70 ±0.15 5.60 ±0.2 High pressure port 10 9 8 7 6 3.0 0.25 14.97 18.03 17.53 10.70 ±0.15 5.0 Ø 2.20 6.26 1 2 3 4 5 7.85 8.95 ±0.5 15.65 16.05 10.16 2.54 0.46 3.10 ±0.2 1.60 ±0.2 5.60 dimensions in mm 2.50 FPS Series Pressure Sensor Page 10 How To Order Series Options FPS Pressure Range Calibration Housing S025 0.1 inH2O (25 Pa) B Differential (Bidirectional) E S050 0.2 inH2O (50 Pa) U Gage (Unidirectional) F S100 0.4 inH2O (100 Pa) S250 FA01 SMT, 2 ports same side FA02 DIP, 2 ports Output 3 non-ratiometric, 3 V supply 6 non-ratiometric, 5 V supply Grade S High 1 inH2O S500 all sensors (250 Pa) 2 inH2O (500 Pa) S250 B F 6 S e www.allsensors.com FPS a 16035 Vineyard Blvd. Morgan Hill, CA 95037 p 408 225 4314 f 408 225 2079 Example: All Sensors reserves the right to make changes to any products herein. All Sensors does 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. All Sensors DS-0329 Rev B Page 11