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Enhanced Digital Output Sensors PCB version
Digital Output Pressure Sensors
• Medical Instrumentation
• Environmental Controls
• HVAC
• Meteorology
Applications
• 5” H2O to 100psi Pressure Ranges
• All Combined Errors Over Temperature Less Than 0.1%, Typical
• Wide -20 to 85°C Compensated Temperature Range
• Enhanced Dual Serial Interface Mode
• Electrically and mechanically compatible with General Sensors GA-
series and Sensym SMRT series.
Features
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® 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.
General Description
Physical Dimensions
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4
Absolute Maximum Ratings
Operating Voltage
Compensated Temperature
Operating Temperature
Storage Temperature
Humidity Limits
+4.75Vdc to +5.25Vdc
-20° C to +85° C
-25 to +90° C
-40 to 125° C
0 to 95% RH
(non condensing)
Environmental Specifications
Supply Voltage (Vcc)
Voltage on Any Pin with Respect to Gnd
Common-mode pressure
Lead Temperature (soldering 2-4 sec.)
7Vdc
-0.6 to Vcc+0.6V
50 psig
250°C
Nominal
0.25
--
--
--
Minimum
--
--
--
--
Parameter (1)
Overall Accuracy (5)
Long Term Drift (one year)
Offset Position Sensitivity (1g)
Offset Warm-up Shift (3)
Maximum
0.5
0.5
0.03
0.25
Units
%FSO
%FSO
%FSO
%FSO
Performance Characteristics for 10 INCH-D-DO-PCB and 1 PSI-D-DO-PCB
Nominal
0.25
--
--
--
Minimum
--
--
--
--
Parameter (1)
Overall Accuracy (5)
Long Term Drift (one year)
Offset Position Sensitivity (1g)
Offset Warm-up Shift (3)
Maximum
0.5
0.5
0.05
0.25
Units
%FSO
%FSO
%FSO
%FSO
Performance Characteristics for 5 INCH-D-DO-PCB
Nominal
--
8
8
Minimum
12
--
--
Parameter (1)
Resolution
Conversion Speed
Supply Current
Maximum
--
16
12
Units
Bit
mS
mA
General Performance Characteristics (All Models)
Standard Pressure Ranges
Operating
Pressure
-5 to 5
-10 to 10
-1 to 1
-5 to 5
-15 to 15
0 to 15
-30 to 30
0 to 30
-100 to 100
0 to 100
Proof
Pressure
200 inH2O
200 inH2O
200 inH2O
10 PSI
60 PSI
60 PSI
90 PSI
90 PSI
200 PSI
200 PSI
Burst
Pressure
300 inH2O
300 inH2O
300 inH2O
30 PSI
120 PSI
120 PSI
150 PSI
150 PSI
250 PSI
250 PSI
Part Number
5 INCH-D-DO-PCB
10 INCH-D-DO-PCB
1 PSI-D-DO-PCB
5 PSI-D-DO-PCB
15 PSI-D-DO-PCB
15 PSI-A-DO-PCB
30 PSI-D-DO-PCB
30 PSI-A-DO-PCB
100 PSI-D-DO-PCB
100 PSI-A-DO-PCB
Digital
Span (4)
1
1
1
1
1
2
2
2
2
2
FSO (2)
5
10
1
5
15
15
30
30
100
100
Units
inH2O
inH2O
PSI
PSI
PSI
PSIA
PSI
PSIA
PSI
PSIA
GA-series
part Number
GA142x0NW10D
GA142x1P1D
GA142x5P5D
GA142x15P15D
GA142x0P15A
GA142x0P30D
GA142x0P30A
GA142x0P100D
GA142x0P100A
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Synchronous Communications
Typical synchronous communications
configuration (compatible with All
Sensors GA142 Series Digital Output
Sensors).
Typical Configurations
Asynchronous Communications
Typical asynchronous communications
configuration. The Mode pin is
interrogated at power up and if tied low,
will cause the sensor to enter asynchro-
nous communications mode. This mode
supports multiple sensors by addressable
commands. The Convert/BR pin then
serves to select one of two available
baud rates.
Host
System Sensor
Convert
/BR
Ready
/Mode
Clock
/SO
Data
/SI
Host
System
Sensor
(1)
Sensor
(n)
Convert/
BR
Ready/
Mode
Clock/
SO
Data/
SI
Convert/
BR
Ready/
Mode
Clock/
SO
Data/
SI
Nominal
0.10
--
Minimum
--
--
Parameter (1)
Overall Accuracy (5)
Long Term Drift (one year)
Maximum
0.25
0.25
Units
%FSO
%FSO
Performance Characteristics for 5 PSI-D-DO-PCB through 100 PSI-x-DO-PCB
Specification Notes
NOTE 1: UNLESS OTHERWISE SPECIFIED, ALL PARAMETERS ARE MEASURED AT 5.0 VOLT SUPPLY, POSITIVE PRESSURE APPLIED TO PORT B.
NOTE 2: THE DIGITAL OUTPUT IS A 16 BIT SIGNED BINARY OUTPUT IN A TWOS 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.
NOTE 3: SHIFT IS WITHIN THE FIRST HOUR OF EXCITATION APPLIED TO THE DEVICE.
NOTE 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.
NOTE 5: OVERALL ACCURACY INCLUDES THE COMBINED EFFECTS OF OFFSET AND SPAN SHIFTS OVER TEMPERATURE, LINEARITY, HYSTERESIS, AND OFFSET AND SPAN
CALIBRATION.
Pressure Conversion Table
10,000
Pout = Digital Output x FSO x Units
32,767
Pout = Digital Output x FSO x Units
Pressure Output EquationMode
S
H
Digital Span Table
-10,399 to 10,399
-399 to 10,399
Mode S (Standard) Mode H (High Res)
-32,767 to 32,766
-999 to 32,766
Span
1
25,054 to 10,399 17,501 to 32,7663
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
Bit 9 through Bit 15 : Reserved
Error Code Table (Asynchronous mode)
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4
Asynchronous Command Summary (1,2)
Command
RD
RM
RO
RP
RR
RS
WD<Mode>
WO<Offset>
U<S/N><Cmd>
Description
Read Mode Setting
Read Model Information
Read User Offset Setting
Read Pressure
Read Device Pressure Range
Read Serial Number
Write Mode Setting (“S” = Standard, “H” = High Resolution)
Write User Offset Setting
Select Unique Part for following command (for multidrop configura-
tions).
t1
t3
t2 t10 t2
t9t4 t8
t6 t7
Bit
15
MSB
Bit
14 Bit
13 Bit
12 Bit
11 Bit
10 Bit
9Bit
8Bit
7Bit
6Bit
5Bit
4Bit
3Bit
2Bit
1Bit
0
LSB
t5
READY [Output]
CONVERT [Input]
CLOCK [Output]
DATA [Output]
Ref Parameter Min Typ Max Units
t1 Conversion Time -- 8 16 msec
t2 Ready to Convert 0-- -- usec
t3 Convert to Clock 24 32 39 usec
t4 Clock Period -- 16 -- usec
t5 Clock High Time -- 8-- usec
Ref Parameter Min Typ Max Units
t6 Data Setup Time -- 3-- usec
t7 Data Hold Time -- 3-- usec
t8 Interbyte Delay -- 57 -- usec
t9 Clock to Ready -- 14 -- usec
t10 Data Transmission -- 335 -- usec
Synchronous Timing Diagram (Note: Asynchronous mode timing is per RS-232)
Response
RD=<Mode>
RM=<Model String>
RO=<hhhh>
RP=<hhhh>
RR=<Range String>
RS=<Serial Number String>
WD=<Mode>
WO=<hhhh>
U<S/N><Cmd>
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.
® MICROWIRE/PLUS IS A REGISTERED TRADEMARK OF NATIONAL SEMICONDUCTOR.
Asynchronous Command Notes
NOTE 1: ALL COMMANDS AND RESPONSES ARE IN ASCII CHARACTER FORMAT AND ARE TERMINATED BY A CARRIAGE RETURN (CARRIAGE RETURNS ARE NOT SHOWN
IN COMMAND AND RESPONSE TABLE). EXAMPLE: THE READ HIGH RESOLUTION PRESSURE COMMAND (REPRESENTED BY: RH< CR>) IS GIVEN BY THE
FOLLOWING THREE BYTE SEQUENCE: 0X52 0X48 0X0D
NOTE 2: <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.
NOTE 3: <LLLL> IS A FOUR BYTE ASCII STRING REPRESENTING THE LOW RESOLUTION OUTPUT (SIMILAR TO THE HIGH RESOLUTION RESPONSE OF NOTE 2)
NOTE 4: <eeee> IS A 16-BIT ERROR CODE. THE REPRESENTATION IS FOUR BYTE ASCII STRING (EXPRESSING A DOUBLE-BYTE OR 16-BITS). ANO ERRORCONDITION
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.
NOTE 5: {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>