CSDX Series
Digital pressure transducers
FEATURES
· 0...25 mbar to 0...5 bar,
0...±10 mbar to 0...±1 bar,
barometric range 800...1100 mbar
· Absolute, gage or differential pressure
· Digital readout via I
2
C-bus
· Precision ASIC conditioning
· Temperature compensated
· Non-ratiometric output
· Total accuracy ±0.5 to ±1.0 %FSS
SPECIFICATIONS
Maximum ratings
ELECTRICAL CONNECTION
N/C
Supply voltage V
S
Lead temperature (2 - 4 sec.)
Temperature ranges
Compensated
Operating
Storage
Vibration
Shock
4.75 V to 5.25 V
DC
max. 6.50 V
DC
6
1
5
+Vs
250°C
CSDX
SCL
SDA
IC
15 nF
220 nF
0 to +85°C
-20 to +105°C
-40 to +125°C
10 g at 20 - 2000 Hz
100 g for 11 ms
Note:
7
2
8 4
3
GND
N/C
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!
Caution!
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.
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CSDX Series
Digital pressure transducers
PRESSURE RANGES SPECIFICATIONS
(V
S
= 5.0 V
DC
, T
A
= 25°C)
Part number
CSDX0811BARO
C S D X 1000A 2R
C S D X 2000A 2R
C S D X 5000A 2R
C S D X 0025D 4R
CSDX0050G2R / D4R
CSDX0100G2R / D4R
CSDX0250G2R / D4R
CSDX0500G2R / D4R
CSDX1000G2R / D4R
CSDX2000G2R / D4R
CSDX5000G2R / D4R
C S D X 0010D 4D
C S D X 0025D 4D
C S D X 0050D 4D
C S D X 0100D 4D
C S D X 0250D 4D
C S D X 0500D 4D
C S D X 1000D 4D
Pressure range
800 to 1100
0 to 1
0 to 2
0 to 5
0 to 25
0 to 50
0 to 100
0 to 250
0 to 500
0 to 1
0 to 2
0 to 5
0 to ±10
0 to ±25
0 to ±50
0 to ±100
0 to ±250
0 to ±500
0 to ±1
bar(d)
mbar
(d)
bar
(g,d)
mbar
(g,d)
bar
(a)
mbar(a)
Burst pressure
1
2
2
4
10
0.2
0.35
0.35
1
1
2
4
10
0.2
0.2
0.35
0.35
1
1
2
bar
(d)
bar
(g,d)
bar
(a)
Sensitivity (typ.)
10.7
3.2
1.6
0.6
128
64
32
12.8
6.4
3.2
1.6
0.6
160
64
32
16
6.4
3.2
1.6
counts/
mbar
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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CSDX Series
Digital pressure transducers
INTRODUCTION
The CSDX 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.
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 CSDX is designed to work as a
slave, hence it will only respond to requests from a master
device.
The I²C-bus master-slave concept requires a unique
address for each device. The CSDX has a hard coded slave
address (1111000xb), therefore it is
not
possible to access
more than one CSDX on the same I²C-bus line.
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 trans-
mitted 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.
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 pur-
pose. When acknowledge is missed, slave transmitter
becomes inactive. It is on master either to send last com-
mand again or to generate STOP condition in that case.
Slave address:
Each device connected to the bus has a
unique slave address. After generating a START con-
dition, the master has to transmit the slave address for
the CSDX with a READ command: $F1. The CSDX must
not be accessed with a WRITE command ($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).
DATA operation:
The CSDX starts to send 2 data bytes containing
the current pressure value placed in the output registers.
DIGITAL I
2
C INTERFACE
The CSDX 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 con-
dition. START conditions are always generated by the
master. Each request for the current pressure value must
be initiated with a START.
SCL
SDA
START
condition
Data
valid
Data allowed
to change
STOP
condition
1
S Slave Address R/W A
Data Byte 1
A
Data Byte 2
S
Slave Address
Next command
P
Read out of pressure value
generated by master
generated by slave
S = START condition
A = Acknowledge
P = STOP condition
Data Byte 1 = High Byte (MSB first)
Data Byte 2 = Low Byte (LSB last)
FIGURE I:
I²C-BUS Protocol of CSDX
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