DSDX Series A-grade Digital pressure transducers FEATURES · 0...1 to 0...100 psi, 0...±1 to 0...±15 psi · Absolute, gage or differential pressure · Digital readout via I2C-bus · Precision ASIC conditioning · Temperature compensated · Non-ratiometric output · Total accuracy ±0.5 to ±1.0 %FSS SPECIFICATIONS ELECTRICAL CONNECTION Maximum ratings N/C Supply voltage VS 6 Lead temperature (2 - 4 sec.) Temperature ranges Compensated Operating Storage Vibration 1 250°C 0 to +85°C -20 to +105°C -40 to +125°C 5 DSDX A-grade Application of supply voltage above the maximum can cause electrical failure. February 2009 / 611 SDA 220 nF IC 3 GND N/C Note: Incorrect applications of excitation voltage or ground to the wrong pin can cause electrical failure. SCL 15 nF 8 4 100 g for 11 ms Caution! The sensor is not reverse polarity protected. 7 2 10 g at 20 - 2000 Hz Shock +Vs 4.75 V to 5.25 VDC max. 6.50 VDC A capacitor of 220 nF is required between +Vs and GND. Pin 2 is an internal device connection and should be connected to ground with a 15 nF capacitor. It is important to place the capacitors as close to the pins as possible! Pins 4, 6 and 8 are internal device connections and should not be connected for any reason! 1/7 www.sensortechnics.com DSDX Series A-grade Digital pressure transducers PRESSURE RANGES SPECIFICATIONS (VS = 5.0 VDC, TA = 25°C) Part number Pressure range Burst pressure1 30 Sensitivity (typ.) DSDX015A2R-A 0 to 15 DSDX030A2R-A 0 to 30 DSDX100A2R-A 0 to 100 150 33 DSDX001G2R-A / D4R-A 0 to 1 5 3277 DSDX005G2R-A / D4R-A 0 to 5 20 655 DSDX015G2R-A / D4R-A 0 to 15 30 218 DSDX030G2R-A / D4R-A 0 to 30 DSDX100G2R-A / D4R-A 0 to 100 DSDX001D4D-A 0 to ±1 5 1638 DSDX005D4D-A 0 to ±5 20 328 DSDX015D4D-A 0 to ±15 30 109 psi(a) psi(g,d) 60 60 150 218 psi(a) psi(g,d) 109 counts/ p si 109 33 Specification notes: 1. If maximum burst pressure is exceeded, even momentarily, the package may leak or burst, or the pressure sensing die may fracture. 2. Span is the algebraic difference between the output signal for the highest and lowest specified pressure. 3. 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. 4. Delay time between sampling and signal change at the output. 5. The smallest change in the output voltage, given any change in pressure. February 2009 / 611 2/7 www.sensortechnics.com DSDX Series A-grade Digital pressure transducers PERFORMANCE CHARACTERISTICS The output signal is not ratiometric to the supply voltage (VS = 5.0 VDC, TA = 25°C) All DSDX...R-A Characteristics Zero pressure offset Min. Typ. Max. DSDX001... 378 410 442 all others 394 410 426 2 3276 Full scale span (FSS) Full scale output 3 Total accuracy (0 to 85°C) counts DSDX001... 3654 3686 3718 all others 3670 3686 3702 DSDX001... ±1.0 all others ±0.5 Sample rate 100 Response delay4 2.73 Units %FSS Hz 14.11 Startup time (power up to 1st result) 40 ms Quantization step5 2 counts Current consumption 6 mA All DSDX...D-A Characteristics Zero pressure offset Min. Typ. Max. DSDX001... 2016 2048 2080 all others 2032 2048 2064 Full scale span (FSS)2 Output Units 3276 at max. specified pressure at min. specified pressure 3 Total accuracy (0 to 85°C) DSDX001... 3654 3686 3718 all others 3670 3686 3702 DSDX001... 378 410 442 all others 394 410 426 DSDX001... ±1.0 all others ±0.5 Sample rate 100 Response delay4 2.73 counts %FSS Hz 14.11 Startup time (power up to 1st result) 40 ms Quantization step5 2 counts Current consumption 6 mA February 2009 / 611 3/7 www.sensortechnics.com DSDX Series A-grade Digital pressure transducers INTRODUCTION The DSDX is capable to generate a digital output signal. It runs a cyclic program, which will store a corrected 12-bit sensor value about every 10 ms within the output registers of the internal ASIC. In order to use the pressure transducer for digital signal readout, the device should be connected to a bidirectional I²C-bus. 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 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. According to the I²C-bus communication 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 DSDX is designed to work as a slave, hence it will only respond to requests from a master device. 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. The I²C-bus master-slave concept requires a unique address for each device. The DSDX has a hard coded slave address (1111000xb), therefore it is not possible to access more than one DSDX on the same I²C-bus line. DIGITAL I2C INTERFACE Slave address: Each device connected to the bus has a unique slave address. After generating a START condition, the master has to transmit the slave address for the DSDX with a READ command: $F1. The DSDX must not be accessed with a WRITE command ($F0) as the correct function of the device can not be guaranteed in this case (note: a power-down power-up change will force the sensor to use factory data again). The DSDX complies with the following protocol (FIGURE I): 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 request for the current pressure value must be initiated with a START. DATA operation: The DSDX starts to send 2 data bytes containing the current pressure value 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 S Slave Address Read out of pressure value generated by master generated by slave P Next command S = START condition Data Byte 1 = High Byte (MSB first) A = Acknowledge Data Byte 2 = Low Byte (LSB last) P = STOP condition FIGURE I: I²C-BUS Protocol of DSDX February 2009 / 611 4/7 www.sensortechnics.com DSDX Series A-grade Digital pressure transducers I2C INTERFACE PARAMETERS Parameter Symbol Input high level Input low level Output low level Pull up current Load capacitance SDA SCL clock frequency Bus free time between STOP and START condition Hold time (repeated) START condition 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 Input filter spike suppression Conditions Min. Typ. 90 0 (open drain, IOL = -4 mA) (pins SCL and SDA) Max. 100 10 10 20 400 100 5 Unit % of Vs µA pF kHz FSC L --- tBUF 4.7 µs 4.0 µs tLOW tHIGH 4.7 4.0 µs µs tSU.STA 4.7 µs tHD.DAT tSU.DAT 0 250 ns ns tR --- 300 ns tF --- 300 ns tSU.STO 4 to first clock pulse tHD.STA tSP tSU;DAT µs sp i ke s o n S D A o r S C L o f that length are suppressed tHD;DAT 50 tSU;STA tHD;STA tR tSU;STO tBUF tHD;STA ns tF SCL SDA tHIGH tLOW SCL SDA FIGURE II: Timing characteristics of the I2C interface February 2009 / 611 5/7 www.sensortechnics.com DSDX Series A-grade Digital pressure transducers PHYSICAL DIMENSIONS D4 package 1.27 typ (0.050 typ) 16.89 (0.665) 7.87 typ (0.310 typ) 13.97 (0.550) 3.63 (0.143) High pressure port 2.29 (0.090) 3.38 (0.133) 8.13 8.89 (0.350) (0.320) 8.26 typ (.325 typ) Low pressure port 0.51 typ (0.02 typ) 1.78 (0.070) 2.54 typ (0.100 typ) 16.64 ±0.64 (0.655 ±0.025) 4.5 (0.177) 6.99 (0.275) G2 package 3.15 (0.124) 1.27 typ (0.050 typ) 13.97 (0.550) 16.89 (0.665) 4.9 (0.193) 2 ° typ 1.19 typ (0.047 typ) 2.29 typ (0.090 typ) 2.79 typ (0.11 typ) 8.89 5.08 (0.350) (0.200) 0.51 typ (0.02 typ) 16.64 ±0.64 (0.655 ± 0.025) 4.5 (0.177) 2.54 typ (0.100 typ) A2 package 16.89 (0.665) 8.46 (0.333) 1.27 typ (0.050 typ) 13.97 (0.550) 2.29 typ (0.090 typ) 8.0 typ (0.315 typ) 8.89 (0.350) 16.64 ±0.64 (0.655 ±0.025) third angle projection February 2009 / 611 4.5 (0.177) 0.51 typ (0.02 typ) 2.54 typ (0.100 typ) dimensions in mm (inches) 6/7 www.sensortechnics.com DSDX Series A-grade Digital pressure transducers ELECTRICAL CONNECTIONS DSDX...D4... Vs (pin 1) identifier +Vs IC GND N/C SCL N/C SDA N/C +Vs IC GND N/C DSDX...A2R-A SCL N/C SDA N/C DSDX...G2R-A Vs (pin 1) identifier Vs (pin 1) identifier +Vs IC GND N/C SCL N/C SDA N/C Note: Pins 4, 6 and 8 are internal device connections and should not be connected for any reason. Pin 2 is an internal device connection and should be connected to ground with a 15 nF capacitor. ORDERING INFORMATION Pressure range Absolute Gage Differential/Gage 0 to 1 psi DSDX001G2R-A DSDX001D4R-A 0 to 5 psi DSDX005G2R-A DSDX005D4R-A 0 to 15 psi DSDX015A2R-A DSDX015G2R-A DSDX015D4R-A 0 to 30 psi DSDX030A2R-A DSDX030G2R-A DSDX030D4R-A 0 to 100 psi DSDX100A2R-A DSDX100G2R-A DSDX100D4R-A 0 to ±1 psi DSDX001D4D-A 0 to ±5 psi DSDX005D4D-A 0 to ±15 psi DSDX015D4D-A Other pressure ranges or calibrations are available on request Sensortechnics reserves the right to make changes to any products herein. Sensortechnics 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. February 2009 / 611 7/7 www.sensortechnics.com