Digital Output Pressure Sensors Enhanced Digital Output Sensors PCB version Features * 5" H2O to 100psi Pressure Ranges * All Combined Errors Over Temperature Less Than 0.1%, Typical * Wide -20 to 85C Compensated Temperature Range * Enhanced Dual Serial Interface Mode * Electrically and mechanically compatible with General Sensors GAseries and Sensym SMRT series. Applications * * * * Medical Instrumentation Environmental Controls HVAC Meteorology General Description The Digital Output pressure sensors are based upon a proprietary surface mapping technology to produce a fully digital output that virtually eliminates all repeatable errors over temperature and pressure. This series provides a 12 bit digital serial output (14 bit in High Resolution Mode) with superior offset, span and linearity characteristics. The output is SPI and MICROWIRE/ PLUS(R) compatible as well as fully compatible with the All Sensors GA142 Series sensors. In addition to synchronous communications, the Digital Output pressure sensors incorporates a bi-directional, TTL level, asynchronous serial interfaces mode (hardware selectable 9,600 or 19,200 baud). This mode includes a command set that allows the host to interrogate the sensor for model information, pressure range, serial number, pressure units and conversion factor. The command set also allows the host to select a high resolution output mode, make minor adjustments to offset and has an addressable feature that alows multiple sensors to be tied to the same interface buss. This series is intended for use with non-corrosive, non-ionic working fluids such as air, dry gases and the like. All signals are 5V TTL/CMOS compatible. Physical Dimensions 4-26 Absolute Maximum Ratings Environmental Specifications 7Vdc Supply Voltage (Vcc) -0.6 to Vcc+0.6V Voltage on Any Pin with Respect to Gnd 50 psig Common-mode pressure 250C Lead Temperature (soldering 2-4 sec.) +4.75Vdc to +5.25Vdc Operating Voltage -20 C to +85 C Compensated Temperature Operating Temperature -25 to +90 C Storage Temperature -40 to 125 C 0 to 95% RH (non condensing) Humidity Limits Standard Pressure Ranges Part Number Operating Units Digital Span Proof (4) Burst Pressure Pressure 1 200 inH2O 300 inH2O GA142x0NW10D 10 1 200 inH2O 300 inH2O PSI GA142x1P1D 1 1 200 inH2O 300 inH2O PSI GA142x5P5D 5 1 10 PSI 30 PSI part Number -5 to 5 inH2O -10 to 10 inH2O 1 PSI-D-DO-PCB -1 to 1 5 PSI-D-DO-PCB -5 to 5 10 INCH-D-DO-PCB FSO (2) 5 Pressure 5 INCH-D-DO-PCB GA-series 15 PSI-D-DO-PCB -15 to 15 PSI GA142x15P15D 15 1 60 PSI 120 PSI 15 PSI-A-DO-PCB 0 to 15 PSIA GA142x0P15A 15 2 60 PSI 120 PSI 30 PSI-D-DO-PCB -30 to 30 PSI GA142x0P30D 30 2 90 PSI 150 PSI 0 to 30 PSIA GA142x0P30A 30 2 90 PSI 150 PSI 100 PSI-D-DO-PCB -100 to 100 PSI GA142x0P100D 100 2 200 PSI 250 PSI 100 PSI-A-DO-PCB 0 to 100 PSIA GA142x0P100A 100 2 200 PSI 250 PSI 30 PSI-A-DO-PCB General Performance Characteristics (All Models) Parameter (1) Minimum Nominal Maximum Units 12 -- -- Bit Conversion Speed -- 8 16 mS Supply Current -- 8 12 mA Minimum Nominal Maximum Units -- 0.25 0.5 %FSO Long Term Drift (one year) -- -- 0.5 %FSO Offset Position Sensitivity (1g) -- -- 0.05 %FSO -- -- 0.25 %FSO Resolution Performance Characteristics for 5 INCH-D-DO-PCB Parameter (1) Overall Accuracy (5) Offset Warm-up Shift (3) Performance Characteristics for 10 INCH-D-DO-PCB and 1 PSI-D-DO-PCB Parameter (1) Minimum Nominal Maximum Units -- 0.25 0.5 %FSO Long Term Drift (one year) -- -- 0.5 %FSO Offset Position Sensitivity (1g) -- -- 0.03 %FSO -- -- 0.25 %FSO Overall Accuracy (5) Offset Warm-up Shift (3) 4-27 4 Performance Characteristics for 5 PSI-D-DO-PCB through 100 PSI-x-DO-PCB Parameter (1) Overall Accuracy Minimum Nominal Maximum Units -- 0.10 0.25 %FSO -- -- 0.25 %FSO (5) Long Term Drift (one year) Specification Notes NOTE NOTE NOTE NOTE NOTE 1: UNLESS OTHERWISE SPECIFIED, ALL PARAMETERS ARE MEASURED AT 5.0 VOLT SUPPLY, POSITIVE PRESSURE APPLIED TO PORT B. 2: THE DIGITAL OUTPUT IS A 16 BIT SIGNED BINARY OUTPUT IN A TWO'S COMPLIMENT FORMAT. THE APPLIED PRESSURE IS COMPUTED USING THE PRESSURE CONVERSION TABLE (BELOW). THE MODE COLUMN IDENTIFIES THE RESOLUTION OPERATING MODE OF THE DEVICE (A = STANDARD RESOLUTION, B = HIGH RESOLUTION). FSO AND UNITS ARE SHOWN FOR EACH MODEL. 3: SHIFT IS WITHIN THE FIRST HOUR OF EXCITATION APPLIED TO THE DEVICE. 4: DIGITAL SPAN IS DEPENDENT ON THE RESOLUTION OPERATING MODE. REFER TO THE DIGITAL SPAN TABLE (BELOW) TO IDENTIFY THE DIGITAL SPAN OF THE SPECIFIC MODEL. IN THE EVENT OF AN OVER-PRESSURE OR UNDER-PRESSURE CONDITION, THE DIGITAL OUTPUT WILL ONE COUNT HIGHER OR ONE COUNT LOWER (RESPECTIVELY) TO THE LISTED DIGITAL SPAN TO INDICATE THE CONDITION. 5: OVERALL ACCURACY INCLUDES THE COMBINED EFFECTS OF OFFSET AND SPAN SHIFTS OVER TEMPERATURE, LINEARITY, HYSTERESIS, AND OFFSET AND SPAN CALIBRATION. Pressure Conversion Table Error Code Table (Asynchronous mode) Mode Bit 0 : Part not compensated Bit 1 : Tdex Overflow Bit 2 : Tdex Over-range Bit 3 : Pdex Overflow Bit 4 : Pdex Over-range Bit 5 : PWL Overflow Bit 6 : Scaling Overflow Bit 7 : High resolution overflow Bit 8 : Pressure Output Limited to Specified Value Pressure Output Equation S Pout = Digital Output x FSO x Units 10,000 H Pout = Digital Output x FSO x Units 32,767 Digital Span Table Bit 9 through Bit 15 : Reserved Span 1 2 3 Mode S (Standard) -10,399 to 10,399 Mode H (High Res) -32,767 to 32,766 -399 to 10,399 5,054 to 10,399 -999 to 32,766 17,501 to 32,766 Typical Configurations Synchronous Communications Asynchronous Communications Typical synchronous communications Typical asynchronous communications configuration (compatible with All configuration. The Mode pin is Sensors GA142 Series Digital Output interrogated at power up and if tied low, Sensors). will cause the sensor to enter asynchro- Sensor Host System (1) Clock/SO Data/SI Convert/BR Ready/Mode nous communications mode. This mode Host System Sensor Clock/SO Data/SI Convert/BR Ready/Mode supports multiple sensors by addressable commands. The Convert/BR pin then serves to select one of two available Sensor (n) Clock/SO Data/SI Convert/BR Ready/Mode baud rates. 4-28 Asynchronous Command Summary (1,2) Command Description Response RD Read Mode Setting RD=<Mode> RM Read Model Information RM=<Model String> RO Read User Offset Setting RO=<hhhh> RP Read Pressure RP=<hhhh> RR Read Device Pressure Range RR=<Range String> RS Read Serial Number RS=<Serial Number String> WD<Mode> Write Mode Setting ("S" = Standard, "H" = High Resolution) WD=<Mode> WO<Offset> Write User Offset Setting WO=<hhhh> U<S/N><Cmd> Select Unique Part for following command (for multidrop configura-U<S/N><Cmd> tions). 4 Asynchronous Command Notes NOTE 1: ALL ASCII CHARACTER FORMAT AND ARE TERMINATED BY A CARRIAGE RETURN (CARRIAGE RETURNS ARE NOT SHOWN EXAMPLE: THE READ HIGH RESOLUTION PRESSURE COMMAND (REPRESENTED BY: RH<CR>) IS GIVEN BY THE FOLLOWING THREE BYTE SEQUENCE: 0X52 0X48 0X0D <hhhh> IS A FOUR BYTE ASCII STRING REPRESENTING A 16-BIT SIGNED VALUE. EXAMPLE: RH=2B7D REPRESENTS THE RESPONSE OF AN RH COMMAND WITH THE PRESSURE OUTPUT OF 0X2B7D (11,133 DECIMAL) VALUE. <LLLL> IS A FOUR BYTE ASCII STRING REPRESENTING THE LOW RESOLUTION OUTPUT (SIMILAR TO THE HIGH RESOLUTION RESPONSE OF NOTE 2) <eeee> IS A 16-BIT ERROR CODE. THE REPRESENTATION IS FOUR BYTE ASCII STRING (EXPRESSING A DOUBLE-BYTE OR 16-BITS). A "NO ERROR" CONDITION IS EXPRESSED AS "0000' WHERE AN ERROR IS EXPRESSED BY SETTING AN INDIVIDUAL BIT OF THE ERROR WORD AND PRESENTING IT IN ASCII HEX FORMAT. {NULL} IS A NULL RESPONSE (NO RESPONSE). THE INTENT UTILITY OF THE COMMAND IS TO APPLY THIS COMMAND IN A MULTIDROP CONFIGURATION (BUSSED CONFIGURATION) AND SIMULANEOUSLY CAPTURE THE PRESSURE OF ALL OF THE DEVICES ON THE BUSS. THE CAPTURED READINGS CAN SUBSEQUENTLY BE READ USING THE U COMMAND (SELECT UNIQUE PART) INCONJUNCTION WITH THE RC COMMAND. EXAMPLE: U<S/N>RC<CR> COMMANDS AND RESPONSES ARE IN IN COMMAND AND RESPONSE TABLE). NOTE 2: NOTE NOTE 3: 4: NOTE 5: Synchronous Timing Diagram (Note: Asynchronous mode timing is per RS-232) READY [Output] t1 t10 t2 t2 CONVERT [Input] t3 t4 t8 t9 t5 CLOCK [Output] t6 t7 DATA [Output] Bit 15 MSB Ref t1 t2 t3 t4 t5 Parameter Conversion Time Ready to Convert Convert to Clock Clock Period Clock High Time Min -0 24 --- Typ 8 -32 16 8 Bit 14 Max 16 -39 --- Bit 13 Bit 12 Bit 11 Units msec usec usec usec usec Bit 10 Bit 9 Bit 8 Ref t6 t7 t8 t9 t10 Bit 7 Bit 6 Bit 5 Parameter Data Setup Time Data Hold Time Interbyte Delay Clock to Ready Data Transmission Bit 4 Bit 3 Min ------ Bit 2 Typ 3 3 57 14 335 Bit 1 Bit 0 LSB Max ------ Units usec usec usec usec usec 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. (R) MICROWIRE/PLUS IS A REGISTERED TRADEMARK OF NATIONAL SEMICONDUCTOR. 4-29