Intersema MS5536C Smd gage pressure module Datasheet

MS5536C (RoHS*)
SMD Gage Pressure MODULE
Pressure range -400 to 1000 mbar
(Optional -1000 to 400 mbar)
0.1 mbar Resolution
Factory Calibrated (coefficients for
software compensation stored onchip)
3-wire serial interface
Low voltage / low power
•
•
•
•
•
DESCRIPTION
MS5536C is a family of high-resolution factory calibrated pressure sensors. The devices include a piezoresistive
pressure sensor and an ADC-Interface IC. The 3-wire serial interface ensures simple communication with any
microcontroller. The devices provide digital pressure and temperature information as 16-Bit data word each. In
addition 64-Bit of individually calibrated compensation coefficients are stored allowing for a highly accurate
software compensation of process spread and temperature effects.
The devices have a very low standby current and automatically enter power down mode after each conversion.
The optimum compromise of refresh rate and average current consumption can be defined by the application
software.
FEATURES
•
•
•
•
•
•
APPLICATIONS
16-Bit ADC resolution
Supply voltage 2.2 V to 3.6 V
Low supply current
-40°C to +85°C
Small size
No external components required
•
•
•
•
Medical application
Blood pressure meter
Air flow measurement
HVAC application
BLOCK DIAGRAM
VDD
MCLK
Input MUX
SENSOR
Digital
Interface
+IN
-IN
ADC
Sensor
Interface IC
DIN
DOUT
dig.
Filter
SCLK
Memory
(PROM)
64 bits
SGND
GND
Fig.: 1 Block Diagram MS5536C
*
The European RoHS directive 2002/95/EC (Restriction of the use of certain Hazardous Substances in electrical and electronic equipment) bans
the use of lead, mercury, cadmium, hexavalent chromium and polybrominated biphenyls (PBB) or polybrominated diphenyl ethers (PBDE).
DA5536C_002.doc
0005536C1245 ECN1126
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1
PIN CONFIGURATION
1
2
3
4
5
6
7
14
13
12
11
10
9
8
14
13
12
11
10
9
8
Top view
1
2
3
4
5
6
7
Bottom view
Fig. 2: Pin configuration of MS5536-CPJU, MS5536-CNJU
PIN DESCRIPTION
Pin Name
Pin
N/C
VDD
MCLK
DIN
DOUT
SCLK
GND
N/C
N/C
N/C
N/C
N/C
PV
PEN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Type
Function
Not Connected
Positive Supply Voltage
Master Clock (32.768kHz)
Data Input
Data Output
Serial Data Clock
Ground
Not Connected
Not Connected
Not Connected
Not Connected
Not Connected
Negative Programming Voltage
Programming Enable
P
I
I
O
I
G
N
I
NOTE
Pins 13 (PEN) and 14 (PV) are only used by the manufacturer for calibration purposes and should not be
connected.
PRESSURE UNIT CONVERSION
mbar
400.0
1000.0
kPa
40.00
100.00
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0005536C1245 ECN1126
bar
0.4000
1.0000
mm Hg
300.0
750.0
PSI
5.801
14.503
August 25th, 2008
atm
0.3947
0.9869
mm H2O
4079
10198
Inches H2O
160.57
401.45
2
ABSOLUTE MAXIMUM RATINGS
Parameter
Symbol
Supply Voltage
Differential Overpressure (1), (2)
CM Overpressure (1), (3)
Storage Temperature (1)
Conditions
VDD
Pdiff
PCM
TStg
Min.
Max
Unit
-0.3
-5
4
5
10
+125
V
bar
bar
o
C
-40
NOTES
1) Storage and operation in an environment of dry and non-corrosive gases.
2) For a differential sensor, Differential Pressure is the difference of pressure at port 1 minus pressure at port
2. For a gage sensor Differential Pressure is the difference of pressure at the port minus pressure of the
ambient air.
3) For a differential sensor Common Mode Pressure is the average of the pressure at port 1 and port 2.
For a gage sensor Common Mode Pressure is the average of the pressure at the port and the pressure of
the ambient air.
RECOMMENDED OPERATING CONDITIONS
(T=25°C, VDD=3.0V unless noted otherwise)
Parameter
Supply Voltage
Supply Current,
average (1)
during conversion (2)
standby (no conversion)
Current consumption into
MCLK (3)
Operating pressure range(4)
Operating pressure range(4)
Operating temperature
range
Conversion time
External clock signal (5)
Duty cycle of MCLK
Serial Data Clock
Symbol
VDD
Conditions
Min.
2.2
Typ.
3.0
Max
3.6
Unit
V
0.1
µA
mA
µA
0.5
µA
1000
400
mbar
mbar
VDD = 3.0 V
Iavg
ISC
Iss
4
1
MCLK=32768Hz
p
p
Pressure Range P devices
Pressure Range N devices
Ta
Tconv
MCLK
-400
-1000
-40
+25
+85
°C
30000
40/60
32768
50/50
35
35000
60/40
500
ms
Hz
%
kHz
MCLK=32768Hz
SCLK
NOTES
1) Under the assumption of one conversion every second. Conversion means either a pressure or a
temperature measurement started by a command to the serial interface of MS5536C.
2) During conversion time the sensor will be switched on and off in order to reduce power consumption; the
total on time within a conversion is about 2 ms. The current specified is active only during this on time.
3) This value can be reduced by switching off MCLK while MS5536C is in standby mode.
4) Positive pressure corresponds to higher pressure at port 1 (nozzle port on plastic cap).
5) It is strongly recommended that a crystal oscillator be used because the device is sensitive to clock jitter. A
square-wave form of the clock signal is a must.
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ELECTRICAL CHARACTERISTICS
DIGITAL INPUTS
Parameter
Symbol
Conditions
Min
Typ
(T=-40°C .. 60°C)
Max
Unit
Input High Voltage
VIH
VDD = 2.2…3.6V
80% VDD
100% VDD
V
Input Low Voltage
VIL
VDD = 2.2…3.6 V
0% VDD
20% VDD
V
Signal Rise Time
tR
200
ns
Signal Fall Time
tf
200
ns
DIGITAL OUTPUTS
Parameter
(T=-40°C .. 60°C, VDD = 2.2V..3.6V)
Min
Typ
Max
Unit
Symbol
Conditions
Output High Voltage
VOH
ISource = 0.6 mA
80% VDD
100% VDD
V
Output Low Voltage
VOL
ISink = 0.6 mA
0% VDD
20% VDD
V
Signal Rise Time
tr
200
ns
Signal Fall Time
tf
200
ns
AD-CONVERTER
Parameter
Symbol
Conditions
Min
Resolution (1)
16
Linear Range
Conversion Time
INL
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0005536C1245 ECN1126
Typ
(T=25°C, VDD =3.0V)
Max
Unit
4000
MCLK=32768Hz
Within linear range
August 25th, 2008
-5
Bit
40000
LSB
35
ms
+5
LSB
4
PRESSURE OUTPUT CHARACTERISTICS
With the calibration data provided by the MS5536C system (stored in the interface IC) the following
characteristics can be achieved:
(VDD=3.0V unless noted otherwise)
Parameter
Conditions
Min
Typ
Max
Unit
Notes
Resolution
Pressure Accuracy
Maximum Error over
Temperature
Maximum Error over
Supply Voltage
0.1
Ta = 10 …+40°C
MS5536-CPJU: p = -100…700 mbar
MS5536-CNJU: p = -700…100 mbar
Ta = 10 ... +40°C
MS5536-CPJU: p = -400…1000 mbar
MS5536-CNJU: p = -1000…400 mbar
Ta = -40…+85°C
p = const.
VDD = 2.2…3.6V
mbar
1
-2.5
2.5
mbar
2
-9
9
mbar
2
-7
+7
mbar
3
1.5
mbar
2
-1.5
0
NOTES
1) A stable pressure reading of the given resolution requires to take the average of 2 to 8 subsequent pressure
values due to noise of the ADC
2) Specified values assume an offset adjustment at any given pressure e.g. p = 0 prior to the measurement
3) Specified values assume quadratic temperature compensation (Refer to the paragraph ‘second-order
temperature compensation‘ in the section ‘FUNCTION’.
TEMPERATURE OUTPUT CHARACTERISTICS
The temperature information is not required for most applications, but it is necessary to allow for temperature
compensation of the pressure output. The reference temperature is 20°C.
Parameter
Resolution
Accuracy
Maximum Change over
Supply Voltage
Conditions
Min
(VDD=3.0V unless noted otherwise)
Typ
Max
Unit
Notes
0.01
°C
at reference temperature
-0.8
0.8
°C
1, 2
Ta = 10…+40°C
-1.5
1.5
°C
1, 2
Ta = -40…+85°C
-1.5
3
°C
1, 2
VDD = 2.2…3.6V
-0.2
0.2
°C
NOTES
1) Refer to the paragraph second-order temperature compensation in the section ‘FUNCTION’
2) ∆p=0
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TYPICAL PERFORMANCE CURVES
ADC-value D1 vs Pressure (typical) for MS5536-CPJU
28000
26000
24000
ADC-value D1 (LSB)
22000
20000
-40°C
25°C
85°C
18000
16000
14000
12000
10000
8000
-400
-300
-200
-100
0
100
200
300
400
500
600
700
800
900
1000
Pressure (mbar)
ADC-value D2 vs Temperature (typical)
50000
45000
ADC-value D2 (LSB)
40000
35000
30000
25000
20000
15000
-40
-20
0
20
40
60
80
Temperature (°C)
Absolute Pressure Accuracy after Calibration for MS5536-CPJU
12
10
Pressure error (mbar)
8
6
85°C
60°C
40°C
4
20°C
0°C
2
0
-400
-300
-200
-100
0
100
200
300
400
500
600
700
800
900
1000
-2
-4
Pressure (mbar)
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Temperature Error Accuracy vs temperature (typical)
15
Temperature error (°C)
10
Temperature error (standard
calculation)
Temperature error (with 2nd
order calculation)
5
0
-5
-40
-20
0
20
40
60
80
Temperature (°C)
Pressure Error Accuracy vs temperature (typical) for MS5536-CPJU
18
16
14
12
Pressure error (mbar)
10
8
Perror(600,1st order)
6
Perror(600,2nd order)
4
Perror(0,1st order)
2
Perror(0,2nd order)
0
-2
-4
-6
-8
-40
-20
0
20
40
60
80
Temperature (°C)
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Pressure error vs supply voltage (typical)
1
0.8
0.6
Pressure error (mbar)
0.4
0.2
0
2.2
2.4
2.6
2.8
3
3.2
3.4
3.6
3.4
3.6
600mbar
0mbar
-0.2
-0.4
-0.6
-0.8
-1
Voltage (V)
Temperature error vs supply voltage (typical)
0.15
Temperature error (°C)
0.1
0.05
0
2.2
2.4
2.6
2.8
3
3.2
-0.05
-0.1
-0.15
Voltage (V)
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FUNCTION
GENERAL
The MS5536C consists of a piezoresistive sensor and a sensor interface IC. The main function of the MS5536C
is to convert the uncompensated analogue output voltage from the piezoresistive pressure sensor to a 16-Bit
digital value, as well as providing a 16-Bit digital value for the temperature of the sensor.
• measured pressure (16-Bit)
• measured temperature (16-Bit)
“D1”
“D2”
As the output voltage of a pressure sensor is strongly dependent on temperature and process tolerances, it is
necessary to compensate for these effects. This compensation procedure must be performed by software using
an external microcontroller.
D1
Pressure
D2
Word1...4
Calculation
in external
microcontroller
Temperature
Sensor
For both pressure and temperature measurement the same ADC is used (sigma delta converter):
• for the pressure measurement, the differential output voltage from the pressure sensor is converted
• for the temperature measurement, the sensor bridge resistance is sensed and converted
During both measurements the sensor will only be switched on for a very short time in order to reduce power
consumption. As both, the bridge bias and the reference voltage for the ADC are derived from VDD, the digital
output data is independent of the supply voltage.
FACTORY CALIBRATION
Each module is individually factory calibrated at two temperatures and two pressures. As a result, 6 coefficients
necessary to compensate for process variations and temperature variations are calculated and stored in the 64Bit PROM of each module. These 64-Bit (partitioned into four words of 16-Bit) must be read by the
microcontroller software and used in the program converting D1 and D2 into compensated pressure and
temperature values.
PRESSURE AND TEMPERATURE MEASUREMENT
The sequence of reading pressure and temperature as well as of performing the software compensation is
depicted in flow chart, Fig. 3 and Fig. 5.
First WORD1 to WORD4 are read through the serial interface. This can be done once after reset of the
microcontroller that interfaces to the MS5536C. Next the compensation coefficients C1 to C6 are extracted using
Bit-wise logical- and shift-operations (refer to Fig. 4 for the Bit-pattern of word 1 to word 4).
For the pressure measurement, the microcontroller has to read the 16-Bit values for pressure (D1) and
temperature (D2) via the serial interface in a loop (for instance once every second). Then, the compensated
pressure is calculated out of D1, D2 and C1 to C6 according to the algorithm in Fig. 3 (possibly using quadratic
temperature compensation according to Fig. 5). All calculations can be performed with signed 16-Bit variables.
Results of multiplications may be up to 32-Bit long (+sign). In the flow according to Fig. 3 each multiplication is
followed by a division. This division can be performed by Bit-wise shifting (divisors are to the power of 2). It is
ensured that the results of these divisions are less than 65536 (16-Bit).
For the timing of signals to read out WORD1 to WORD4, D1, and D2 please refer to the paragraph ‘Serial
Interface’.
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Basic equations:
System
initialisation
Start
Example:
Read calibration data (factory calibrated) from
PROM of MS5536
Word1 = 45834
Word2 = 61787
Word3 = 49110
Word4 = 4060
Word1, Word2, Word3 and Word4 (4x16 Bit)
Convert calibration data into coefficients:
(see bit pattern of Word1-Word4)
Pressure and temperature measurement
C1: Pressure sensitivity
(13 Bit)
C2: Pressure offset
(13 Bit)
C3: Temperature coefficient of pressure sensitivity (9 Bit)
C4: Temperature coefficient of pressure offset
(9 Bit)
C5: Reference Temperature
(12 Bit)
C6: Temperature coefficient of the temperature
(8 Bit)
SENST1
OFFT1
TCS
TCO
Tref
TEMPSENS
C1 = 4054
C2 = 4060
C3 = 179
C4 = 241
C5 = 2826
C6 =
91
Calculate calibration temperature
UT1=4*C5+15136
D1 = 15832
Read digital pressure value from MS5536
D1 (16 Bit)
D2 = 28877
Read digital temperature value from MS5536
UT1= 26440
28877
D2 (16 Bit)
Calculate actual temperature
Difference between actual temperature and reference
temperature:
dT = D2 - UT1
Actual temperature:
dT(D2) = D2 - Tref
dT
TEMP(D2)=20°+dT(D2)*TEMPSENS
TEMP = 3680
= 36.80 °C
OFF(D2)=OFFT1+TCO*dT(D2)
OFF
SENS(D2)=SENST1+TCS*dT(D2)
SENS = 14710
9
TEMP = 2000 + dT*(C6+262)/2 (weight: 0.01°C)
= 2437
Calculate temperature compensated pressure
Offset at actual temperature:
OFF = C2 +10381+ ((C4-243)*dT)/212
Sensitivity at actual temperature:
= 14440
SENS = C1 + 10179+((C3+222)*dT)/211
12
X = (SENS * (D1-OFF))/2
X
= 4999
P
= 9998
= 99.98 mmHg
Temperature compensated pressure:
P = 2X
(weight: 0.01mmHg)
P = X*1365/29
(weight: 0.01mbar)
P(D1,D2)= SENS(D2)*(D1- OFF(D2))
Display pressure and temperature value
Fig. 3: Flow chart for pressure/temperature reading and software compensation.
NOTES
1) Readings of D2 can be done less frequently, but the display will be less stable in this case
2) For a stable display of 0.1 mm Hg resolution or below, it is recommended to display the average of at least 8
subsequent pressure values.
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10
C3/II (8-Bit)
Word 1
DB7
DB6
DB5
DB4
DB3
C5/II(8-Bit)
DB2
DB1
DB0
DB7
DB6
DB5
C4/II (8-Bit)
Word 2
DB7
DB6
DB5
DB4
DB3
Word 4
DB11
DB10
DB9
C1/I
C4/I
C3/I
DB12
DB8
DB8
DB3
DB2
DB1
DB0
C6(8-Bit)
DB2
DB1
DB0
DB7
C5/I (4-Bit)
Word 3
DB4
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB5
DB4
DB3
DB2
DB1
DB0
DB5
DB4
DB3
DB2
DB1
DB0
C1/II (12-Bit)
DB8
DB11
DB10
DB9
DB8
DB7
DB6
C2 (13-Bit)
DB12
DB11
DB10
DB9
DB8
DB7
DB6
Fig. 4: Arrangement (Bit-pattern) of calibration data in Word1 to Word4.
SECOND-ORDER TEMPERATURE COMPENSATION
In order to obtain full accuracy over the whole temperature range, it is recommended to compensate for the
non-linearity of the output of the temperature sensor. This can be achieved by the second-order temperature
calculation, i.e. by replacing the block ‘Calculate actual temperature’ in flow chart Fig. 3 by the following
sequence:
D2≥UT1?
no
yes
Calculate actual temperature
Calculate actual temperature
Difference between the actual temperature and
reference temperature:
18
dT = (D2 - UT1) - ((D2-UT1)*(D2-UT1))/2
Actual temperature in °C
9
TEMP = 2000 + dT*(C6+262)/2 (weight: 0.01°C)
Difference between the actual temperature and
reference temperature:
18
dT = (D2 - UT1) - (9*(D2-UT1)*(D2-UT1))/2
Actual temperature in °C
9
TEMP = 2000 + dT*(C6+262)/2 (weight: 0.01°C)
Fig. 5: Flow chart for calculating the temperature to the optimum accuracy. The value for dT thus obtained is
then used for the calculation of the temperature compensated pressure as shown in Fig. 3.
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SERIAL INTERFACE
The MS5536C communicates with microprocessors and other digital systems via a 3-wire synchronous serial
interface as shown in Fig. 1. The SCLK (Serial Clock) signal initiates the communication and synchronizes the
data transfer with each Bit being sampled by the MS5536C on the rising edge of SCLK and each Bit being sent
by the MS5536C on the rising edge of SCLK. The data should thus be sampled by the microcontroller on the
falling edge of SCLK and sent to the MS5536C with the falling edge of SCLK. The SCLK-signal is generated by
the microprocessor’s system. The digital data provided by the MS5536C on the DOUT pin is either the
conversion result or the software calibration data. In addition the signal DOUT (Data Out) is also used to indicate
the conversion status (conversion-ready signal, see below). The selection of the output data is done by sending
the corresponding instruction on the pin DIN (Data Input).
Following is a list of possible output data instructions:
•
•
•
•
•
Conversion start for pressure measurement and ADC-data-out
Conversion start for temperature measurement and ADC-data-out
Calibration data read-out sequence for word 1 and word 3
Calibration data read-out sequence for word 2 and word 4
RESET sequence
“D1”
“D2”
(Figure 6a)
(Figure 6b)
(Figure 6c)
(Figure 6d)
(Figure 6e)
Every communication starts with an instruction sequence at Pin DIN. Fig. 6 shows the timing diagrams for the
MS5536C. The device does not need a ‘Chip select’ signal. Instead there is a Start Sequence (3-Bit high) before
each Setup Sequence and Stop Sequence (3-Bit low) after each Setup Sequence. The Setup Sequence consists
in 4-Bit that select a reading of pressure, temperature or calibration data. In case of pressure- (D1) or
temperature- (D2) reading the module acknowledges the start of a conversion by a low to high transition at Pin
DOUT during the last Bit of the Stop Sequence.
Two additional clocks at SCLK are required after the acknowledge signal. Then SCLK is to be held low by the
microcontroller until a high to low transition on DOUT indicates the end of the conversion.
This signal can be used to create an interrupt in the microcontroller. The microcontroller may now read out the
16-Bit word by giving another 17 clocks on the SLCK pin. It is possible to interrupt the data read-out sequence
with a hold of the SCLK signal. It is important to always read out the last conversion result before starting a
new conversion.
Conversion start for pressure measurement and ADC-data-out "D1":
end of conversion
start of conversion
conversion
(33ms)
ADC-data out MSB
DB7 DB6 DB5 DB4 DB3 DB2 DB1
DIN
DOUT SCLK
The RESET-sequence is special as its unique pattern is recognized by the module in any state. By consequence
it can be used to restart if synchronization between the microcontroller and the MS5536C has been lost. This
sequence is 21-Bit long. The DOUT signal might change during that sequence (see Fig. 6e). It is recommended
to send the RESET sequence before first conversion sequence to avoid hanging up the protocol permanently in
case of electrical interference.
ADC-data out LSB
DB0 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
sequence: START+P-measurement
Bit0 Bit1 Bit2 Bit3 Bit4 Bit5 Bit6 Bit7 Bit8 Bit9
Start-bit
Setup-bits
Stop-bit
Fig. 6a: D1 acquisition sequence
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end of conversion
conversion
(33ms)
start of conversion
ADC-data out MSB
DB7 DB6 DB5 DB4 DB3 DB2 DB1
DIN
DOUT SCLK
Conversion start for temperature measurement and ADC-data-out "D2":
ADC-data out LSB
DB0 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
sequence: START+T-measurement
Bit0 Bit1 Bit2 Bit3 Bit4 Bit5 Bit6 Bit7 Bit8 Bit9
Start-bit
Setup-bits
Stop-bit
DIN
DOUT SCLK
Fig. 6b: D2 acquisition sequence
Calibration data read out sequence for word 1/ word 3:
coefficient-data out MSB
DB7 DB6 DB5 DB4 DB3 DB2 DB1
coefficient-data out LSB
DB0 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
sequence: coefficient read + address
Bit0 Bit1 Bit2
Bit3 Bit4 Bit5 Bit6 Bit7 Bit8 Bit9 Bit10 Bit11
Setup-bits
Start-bit
Stop-bit
address word 1
address word 3
DIN
DOUT SCLK
Fig. 6c: W1, W3 reading sequence
Calibration data read out sequence for word 2/ word 4:
coefficient-data out MSB
DB7 DB6 DB5 DB4 DB3 DB2 DB1
coefficient-data out LSB
DB0 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
sequence: coefficient read + address
Bit0 Bit1 Bit2 Bit3 Bit4 Bit5 Bit6 Bit7 Bit8 Bit9 Bit10 Bit11
Setup-bits
Start-bit
Stop-bit
address word 2
address word 4
Fig. 6d: W2, W4 reading sequence
DIN
DOUT SCLK
RESET - sequence:
sequence: RESET
Bit0 Bit1 Bit2 Bit3 Bit4 Bit5 Bit6 Bit7 Bit8 Bit9 Bit10 Bit11Bit12 Bit13 Bit14 Bit15
Fig. 6e: Reset sequence (21-Bit)
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APPLICATION INFORMATION
GENERAL
The MS5536C consists in a sensor die and a mixed signal interface IC on a single ceramic substrate with Pb-free
leads attached. It is compatible with standard PCB-assembly technologies (Pick and Place followed by IR-reflow
soldering). Single sided PCB layout is possible. The device directly interfaces to a standard microcontroller, no
costly external components like Instrumentation Amplifiers or A/D converters are required. A mark on the
ceramic substrate indicates pin 1 (see Fig. 2).
The silicon pressure transducer, the IC and the bonding wires are protected against humidity by a silicone gel
and against mechanical damage by a plastic cap. The cap is also used as the pressure port. The MS5536C does
not show pressure hysteresis effects.
The simple digital 3 wire synchronous serial interface eliminates all sensitive analogue signal lines on the PCB
with their often critical routing and guarding issues. The protocol does not require specific interface cells and can
be implemented on any microcontroller using standard I/Os. The required external clock-signal of 32.768 kHz is
standard in the watch industry and readily available in most hand-held applications.
The MS5536C is well suited for battery powered portable devices. This is due to the low supply voltage of 2.2V
and the small amount of computing power required to calculate the compensated values for pressure and
temperature (use of 4-Bit microcontrollers is possible). No costly end-of-line calibrations are required as the
MS5536C contains factory stored calibration coefficients.
In order to further enhance accuracy it is recommended to periodically recalibrate the device offset in the
application software. This can be achieved by reading the compensated pressure in a known state, preferably at
∆p=0 (e.g. Blood Pressure Meters with vent open). The detected difference between displayed and actual
pressure can be memorized and subtracted from following readings.
The pressure range and port configurations make the MS5536C well suited for applications like blood-pressure
metering, air flow and pressure measurements in HVAC-systems and liquid level detection.
3V-Battery
LCD-Display
VDD
XTAL1
32.768 kHz
MS5536
VDD
47µF
Tantal
XTAL2
Keypad
MCLK
DIN
DOUT
SCLK
GND
4/8bit-Microcontroller
GND
EEPROM
optional
Fig. 7: Application example of the MS5536C for a battery powered device
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DEVICE PACKAGE OUTLINES
All dimension in mm
Fig. 8: Device package outlines of MS5536-CPJU / MS5536-CNJU
10.8 [0.425]
0.7 [0.028]
1.27 [0.050]
PAD LAYOUT FOR MS5536-C
1.3 [0.051]
All dimension in mm [inch]
Fig. 9: recommended pad-layout for MS5536-CPJU / MS5536-CNJU
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ASSEMBLY
DECOUPLING CAPACITOR
Particular care must be taken when connecting the device to power supply. A 47 µF tantalum capacitor must be
placed as close as possible of the MS5536C's VDD pin. This capacitor will stabilise the power supply during data
conversion and thus, provide the highest possible accuracy.
SOLDERING
Please refer to the application note AN808 for all soldering issues.
MOUNTING
The MS5536C can be placed with automatic Pick&Place equipment using a special vacuum nozzle. It will not be
damaged by the vacuum.
For a good mechanical stability, it is important to solder all contact pads. The Pins PEN and PV must be left
open or connected to Vdd. Do not connect to GND!
LIGHT SENSITIVITY
The MS5536C is protected against sunlight by the
cap on frontside. It is, however, important to note
that the sensor may still be slightly sensitive to
sunlight, especially to infrared light sources (Light
may also enter the negative pressure port on
backside). This is due to the strong photo effect of
silicon. As the effect is reversible there will be no
damage, but the user has to take care that in the
final product the sensor cannot be exposed to direct
light during operation. This can be achieved for
instance by placing mechanical parts with holes in
such that light cannot pass.
CONNECTING THE PRESSURE PORT
The best connection to the pressure port is
achieved with a flexible tube fitted to the full length
of the nozzle. Care should be taken to keep the
nozzle clean. The tube should be flexible enough to
minimize the mechanical stress on the module (see
Fig. 10)
Fig. 10: connection to pressure port
CLEANING
The MS5536C has been manufactured under cleanroom conditions. It is therefore recommended to assemble
the sensor under class 10’000 or better conditions. Should this not be possible, it is recommended to protect the
sensor opening during assembly from entering particles and dust. To avoid cleaning of the PCB, solder paste of
type ‘No-Clean’ shall be used.
CLEANING MIGHT DAMAGE THE SENSOR!
ESD PRECAUTIONS
The electrical contact pads are protected against ESD according to 4 kV HBM (human body model). It is
therefore essential to ground machines and personal properly during assembly and handling of the device. The
MS5536C is shipped in antistatic transport boxes. Any test adapters or production transport boxes used during
the assembly of the sensor shall be of an equivalent antistatic material.
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ORDERING INFORMATION
Product Code
MS5536-CPJU
MS5536-CNJU
Product
SMD Gage
Pressure
Module RoHS
SMD Gage
Pressure
Module RoHS
Art.-Nr.
325536008
325536009
Package
Gage with plastic cap,
upright nozzle, vent hole
on backside, J-Lead type
Gage with plastic cap,
upright nozzle, vent hole
on backside, J-Lead type
Comments
Pressure Range
(port1 – port2):
-400 mbar …+1000 mbar
Pressure Range
(port1 – port2):
-1000 mbar …+400 mbar
FACTORY CONTACTS
Intersema Sensoric SA
Ch. Chapons-des-Prés 11
CH-2022 BEVAIX
SWITZERLAND
Tel. (032) 847 9550
Tel. Int. +41 32 847 9550
Telefax +41 32 847 9569
e-mail:
http://www.intersema.ch
NOTICE
Intersema reserves the right to make changes to the products contained in this data sheet in order to improve the design or performance
and to supply the best possible products. Intersema assumes no responsibility for the use of any circuits shown in this data sheet,
conveys no license under any patent or other rights unless otherwise specified in this data sheet, and makes no claim that the circuits are
free from patent infringement. Applications for any devices shown in this data sheet are for illustration only and Intersema makes no claim
or warranty that such applications will be suitable for the use specified without further testing or modification.
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