SSI Series Amplified stainless steel pressure sensors FEATURES · 200 mbar to 35 bar, 3 to 500 psi absolute, gage or vacuum pressure (custom pressure ranges on request) · Amplified analog output and I²C bus interface (SPI on request) · Precision ASIC signal conditioning · Calibrated and temperature compensated · Rugged stainless steel isolated package · RoHS compliant · Quality Management System according to ISO 13485:2003 and ISO 9001:2008 MEDIA COMPATIBILITY Wetted materials: Stainless steel 316/316 L SPECIFICATIONS ELECTRICAL CONNECTION Maximum ratings Supply voltage VS Temperature ranges Compensated Operating Storage Insulation resistance Proof pressure1 Burst pressure2 4.5 V ... 5.5 VDC max. 6.50 VDC -20 ... +85 °C -40 ... +120 °C -40 ... +120 °C 100 MΩ at 100 VDC 2 x rated pressure 4 x rated pressure Pin 1 2 3 4 5 6 7 Connection +Vs GND Vout I/C* SC L SD A I/C* * Internal connection. Do not connect for any reason E / 11671 / D 1/7 www.first-sensor.com www.sensortechnics.com SSI Series Amplified stainless steel pressure sensors PERFORMANCE CHARACTERISTICS (VS = 5.0 VDC, TA = 25°C, analog output signal is ratiometric to VS, digital output signal is not ratiometric to VS) Characteristics Total accuracy (-20...85 °C)4 Response delay5, 6 A/D resolution6 D/A resolution Current consumption7 Min. Typ. Max. ±1.5 2 13 11 5 Units %FSS ms bi t mA A N A L O G U E P E R F O R M A N C E C H A R A C T E R IS T IC Output at min. specified pressure Full scale span (FSS)3 Full scale output 0.44 4.44 0.50 4.00 4.50 0.56 V 4.56 D IG IT A L P E R F O R M A N C E C H A R A C T E R IS T IC Output at min. specified pressure Full scale span (FSS)3 Full scale output 2883 29097 3277 26214 29490 3670 counts 29883 Specification notes: 1. Proof pressure is the maximum pressure which may be applied without causing durable shifts of the electrical parameters of the sensing element. 2. Burst pressure is the maximum pressure which may be applied without causing damage to the sensing element or leaks to the housing. 3. Full Scale Span (FSS) is the algebraic difference between the output signal for the highest and lowest specified pressure. 4. Total accuracy is the combined error from offset and span calibration, linearity, pressure hysteresis, and temperature effects. Linearity is the measured deviation based on a straight line. Hysteresis is the maximum output difference at any point within the operating pressure range for increasing and decreasing pressure. Calibration errors include the deviation of offset and full scale from nominal values. 5. Max. delay time between pressure change at the pressure die and signal change at the output. 6. The response time depends on the adjusted internal A/D resolution of the sensor. For 13 bit it is typ. 2 ms. Other A/D resolutions and reponse time are available on request. Please contact First Sensor for further information. 7. Sensors with lower current consumption are available on request. Please contact First Sensor for further information. E / 11671 / D 2/7 www.first-sensor.com www.sensortechnics.com SSI Series Amplified stainless steel pressure sensors I²C BUS Introduction DATA valid (D): State of data line represents valid data when, after START condition, data line is stable for duration of HIGH period of clock signal. Data on line must be changed during LOW period of clock signal. There is one clock pulse per bit of data. The sensor is capable to generate a digital output signal. The device runs a cyclic program, which will store a corrected pressure value with 13 bit resolution about every 500 µs within the output registers of the internal ASIC. In order to use the sensor for digital signal readout, it should be connected to a bidirectional I²C-bus. Acknowledge (A): Data is transferred in pieces of 8 bits (1 byte) on serial bus, MSB first. After each byte receiving device – whether master or slave – is obliged to pull data line LOW as acknowledge for reception of data. Master must generate an extra clock pulse for this purpose. When acknowledge is missed, slave transmitter becomes inactive. It is on master either to send last command again or to generate STOP condition in that case. According to the I²C-bus specification, the bus is controlled by a master device, which generates the clock signal, controls the bus access and generates START and STOP conditions. The sensor is designed to work as a slave, hence it will only respond to requests from a master device. Digital I²C interface Slave address: The I²C-bus master-slave concept requires a unique address for each device. The sensor has a preconfigured slave address (1111000xb). By factory programming it is possible to define a secondary slave address additional to the general one. According to I²C specification 127 different addresses are available. The sensor will then listen to both slave addresses. After generating a START condition the master sends the address byte containing a 7 bit address followed by a data direction bit (R/W). A "0" indicates a transmission from master to slave (WRITE), a "1" indicates a data request (READ). The sensor complies with the following protocol (Fig. 1): Bus not busy: During idle periods both data line (SDA) and clock line (SCL) remain HIGH. START condition (S): HIGH to LOW transition of SDA line while clock (SCL) is HIGH is interpreted as START condition. START conditions are always generated by the master. Each initial request for a pressure value has to begin with a START condition. STOP condition (P): LOW to HIGH transition of SDA line while clock (SCL) is HIGH determines STOP condition. STOP conditions are always generated by the master. More than one request for the current pressure value can be transmitted without generation of intermediate STOP condition. DATA operation: The sensor starts to send 2 data bytes containing the current pressure value as a 15 bit information placed in the output registers. SCL SDA START condition Data valid 1 S Slave Address R/W A Data allowed to change Data Byte 1 A STOP condition Data Byte 2 Read out of first pressure value generated by master generated by slave A Data Byte 1 P Read out of n pressure values (optional) S = START condition Data Byte 1 = High Byte (MSB first) A = Acknowledge Data Byte 2 = Low Byte (LSB last) P = STOP condition Fig. 1: I²C bus protocol E / 11671 / D 3/7 www.first-sensor.com www.sensortechnics.com SSI Series Amplified stainless steel pressure sensors I²C Interface Parameters Parameter Symbol Input high level Input low level Output low level Pull-up resistor Load capacitance @ SDA Input capacitance @ SDA/SCL SCL clock frequency Bus free time between STOP and START condition Hold time (repeated) START condition, to first clock pulse LOW period of SCL HIGH period of SCL Setup time repeated START condition Data hold time Data setup time Rise time of both SDA and SCL Fall time of both SDA and SCL Setup time for STOP condition Min. Typ. 90 0 Max. Unit 100 10 10 % of V s Ω 500 C SD A CI2C_IN FSC L tBUF tHD.STA tLOW tHIGH tSU.STA tHD.DAT tSU.DAT tR tF tSU.STO 400 10 400 100* 1.3 0.8 1.3 0.6 1 0 0.2 pF kHz µs 0.3 0.3 0.6 * recommended Note: First Sensor recommends communication speeds of at least 100 kHz (max. 400 kHz). Please contact First Sensor for further information. tSU;DAT tHD;DAT tSU;STA tHD;STA tR tSU;STO tBUF tHD;STA tF SCL SDA tHIGH tLOW SCL SDA Fig. 2: Timing characteristics E / 11671 / D 4/7 www.first-sensor.com www.sensortechnics.com SSI Series Amplified stainless steel pressure sensors PHYSICAL DIMENSIONS SSI...1 (weld ring) Wires, 100 mm Vent tube Ø 16.4 Ø 1.6 O-ring groove recommended size 15.6 x 1.78 5.0 5.5 2.4 13.0 3.0 Ø 15.0 Do not touch diaphragm! Ø 18.4 Ø 19.0 mass: approx. 17 g +0,00 mm -0,05 mm dimensions in mm A clearance fit 19H8 with 20 ° phase is recommended for mounting. SSI...5 (1/4 " NPT) Wires, 100 mm Ø 19.0 Vent tube Ø 1.6 5.0 28.50 SW 20 R1 10.0 6.0 Ø 4.4 mass: approx. 50 g E / 11671 / D 1/4 NPT dimensions in mm 5/7 www.first-sensor.com www.sensortechnics.com SSI Series Amplified stainless steel pressure sensors PHYSICAL DIMENSIONS SSI...9 (G 1/8 " HEX) Wires, 100 mm Vent tube Ø 19.0 Ø 1.6 5.0 SW 20 28.5 6.0 10.0 O-ring groove recommended size 11x2 Ø 4.4 mass: approx. 35 g dimensions in mm G 1/8 OPTIONAL PRESSURE FITTING SSI...N (1/4 " NPT fitting for G 1/8 " thread) 1/4 NPT 11.5 18 SW 14 G 1/8 Other fittings are available on request. Please contact First Sensor. E / 11671 / D 6/7 www.first-sensor.com www.sensortechnics.com SSI Series Amplified stainless steel pressure sensors ORDERING INFORMATION Series Pressure range Options SSI M200 200 mbar M700 700 mbar B 001 1 bar B 3x5 3.5 bar B 010 10 bar B 020 20 bar B 035 35 bar P 003 3 p si P 010 1 0 p si P 015 1 5 p si P 050 5 0 p si P 150 1 5 0 p si P 300 3 0 0 p si P 500 5 0 0 p si Pressure mode A* G SSI B 001 G * only available as SSIM200GV... (0...-200 mbar) U Electrical connection Housing Absolute U Unidirectional 1 Gage V* Vacuum 5* 9 N** * only available from700 mbar. MOQ may apply Example: Calibration Weld ring 1/4" NPT G 1/8" HEX 1/4" NPT fitting * MOQ may apply ** 1/4" NPT fitting on G 1/8" thread 9 A AMPMODU* Grade Supply H High 5 5V H 5 * TYCO 5-103956-6 A Custom pressure ranges, higher accuracy, SPI bus interface, 3 V supply and other pressure fittings are available on request. MOQ may apply. Please contact First Sensor. First Sensor reserves the right to make changes to any products herein. First Sensor 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. E / 11671 / D 7/7 www.first-sensor.com www.sensortechnics.com