Sensortechnics DSDXL010D4R Digital pressure transducer Datasheet

DSDXL Series
Digital pressure transducers
FEATURES
GENERAL DESCRIPTION
The DSDXL series offers a digital
interface on a very cost-effective basis.
This family is fully calibrated and
temperature compensated using an
on-board ASIC. These sensors are
intended for use with non-corrosive,
non-ionic working fluids such as air
and dry gases.
· 0...±5, 0...±10, 0...10 "H2O
differential/gage
· Digital readout via I2C-bus
· Precision ASIC conditioning
· Temperature compensated
· Non-ratiometric output
The DSDXL010D4R device is
available to measure gage pressure
from 0...10 "H2O.
APPLICATIONS
The DSDXL...4D devices are available
to measure differential pressures from
0...±5 "H 2 O (DSDXL005D4D) to
0...±10 "H 2 O (DSDXL010D4D).
Differential devices allow application
of pressure to either side of the
sensing diaphragm and can be used
for gage or differential measurements.
· Medical instrumentation
· HVAC controls
· Pneumatic controls
All DSDXL devices are accurate to
within ±2.5 %FSS. The devices are
characterized for operation from a
single 5 V supply. The sensor is
designed
and
manufactured
according to standards laid down in
ISO 9001.
ELECTRICAL CONNECTION
+Vs
N/C
Note:
6
1
5
7
DSDXL
2
8 4
N/C
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SCL
SDA
220 nF
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!
IC
15 nF
3
A capacitor of 220 nF is required
between +Vs and GND.
Pins 4, 6 and 8 are internal device
connections and should not be
connected for any reason!
GND
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DSDXL Series
Digital pressure transducers
PRESSURE SENSOR CHARACTERISTICS
Environmental specifications
Maximum ratings
Supply voltage VS
Output current
Sink
Source
2 mA (max.)
2 mA (max.)
Lead temperature (2 - 4 sec.)
250°C
Common mode pressure
50 psi
Caution!
Temperature ranges
Compensated
Operating
Storage
4.75 V to 5.25 VDC
max. 6.50 VDC
0 to +85°C
-20 to +105°C
-40 to +125°C
Vibration:
10 g at 20 - 2000 Hz
Shock:
50 g for 11 ms
The sensor is not reverse polarity protected.
Incorrect applications of excitation voltage or ground to the wrong pin can cause electrical failure.
Application of supply voltage above the maximum can cause electrical failure.
PERFORMANCE CHARACTERISTICS
(VS = 5.0 VDC, TA = 25°C)
Part number
Pressure range
D S D X L005D 4D
0...±5
D S D X L010D 4D
0...±10
D S D X L010D 4R
0...10
Burst pressure1
3
"H2O
3
3
Sensitivity (typ.)
328
p si
164
328
counts/
"H2O
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.
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DSDXL Series
Digital pressure transducers
PERFORMANCE CHARACTERISTICS
The output signal is not ratiometric to the supply voltage (VS = 5.0 VDC, TA = 25°C)
DSDXL...D4D
Characteristics
Zero pressure offset
Min.
Typ.
Max.
1966
2048
2130
Full scale span (FSS)2
Units
3276
counts
Output
at max. specified pressure
3604
3686
3768
at min. specified pressure
327
410
492
Total accuracy (0 to 85°C)3
±2.5
Sample rate
100
Response delay4
2.73
%FSS
Hz
14.11
ms
Startup time (power up to 1st result)
40
Quantization step5
3
counts
Current consumption
6
mA
DSDXL010D4R
Characteristics
Zero pressure offset
Min.
Typ.
Max.
327
410
492
Full scale span (FSS)2
Full scale output
counts
3277
3604
3686
Total accuracy (0 to 85°C)3
3768
±2.5
Sample rate
100
Response delay4
2.73
Units
%FSS
Hz
14.11
ms
Startup time (power up to 1st result)
40
Quantization step5
3
counts
Current consumption
6
mA
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DSDXL Series
Digital pressure transducers
INTRODUCTION
The DSDXL 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 DSDXL 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 DSDXL has a hard coded
slave address (1111000xb), therefore it is not possible to
access more than one DSDXL 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 DSDXL with a READ command: $F1. The DSDXL
must not be accessed with a WRITE command ($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 DSDXL complies with the following protocol (FIG. 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 DSDXL 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 DSDXL
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DSDXL Series
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
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DSDXL Series
Digital pressure transducers
ELECTRICAL CONNECTIONS
Vs (pin 1)
identifier
Note: Pins 4, 6 and 8 are internal device
connections and should not be
connected for any reason.
+Vs
IC
GND
N/C
SCL
N/C
SDA
N/C
Pin 2 is an internal device connection
and should be connected to ground
with a 15 nF capacitor.
PHYSICAL DIMENSIONS
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)
1.78
(0.070)
16.64 ±0.64
(0.655 ±0.025)
third angle projection
Low pressure port
0.51 typ
(0.02 typ)
2.54 typ
(0.100 typ)
4.5
(0.177)
dimensions in mm (inches)
ORDERING INFORMATION
Pressure range
Differential/Gage
0...±5 "H2O
D S D X L005D 4D
0...±10 "H2O
D S D X L010D 4D
0...10 "H2O
D S D X L010D 4R
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.
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