MS5536C SMD Gage Pressure Module
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0005536C1245 ECN1511 1/18
• Pressure range -400 to 1000 mbar
(Optional -1000 to 400 mbar)
• 0.1 mbar Resolution
• Factory Calibrated (coefficients for software
compensation store on-chip)
• 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 eac h. 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
•
Medic al a pp lic atio n
•
Supply voltage 2.2 V to 3.6 V
•
Blood pressure meter
•
Low supply current
•
Air flow measurement
•
-40°C to +85°C
•
HVAC application
•
Small size
•
No external components required
BLOCK DIAGRAM
VDD
GND
MCLK
SCLK
DOUT
DIN
Input MUX
ADC
Digital
Interface
Memory
(PROM)
64 bits
SENSOR
SGND
+IN
-IN
dig.
Filter
Sensor
Interface IC
Fig. 1: Block diagram MS5536C
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PIN CONFIGURATION
1
2
3
4
5
6
7
14
13
12
11
10
9
8
1
2
3
4
5
6
7
14
13
12
11
10
9
8
Top view
Bottom view
Fig. 2: Pin configuration of MS5536-CPJU, MS5536-CNJU
PIN DESCRIPTION
Pin Name
Pin
Type
Function
N/C
1
Not Connected
VDD
2
P
Positive Supply Voltage
MCLK
3
I
Master Clock (32.768kHz)
DIN
4
I
Data Input
DOUT
5
O
Data Output
SCLK
6
I
Serial Data Clock
GND
7
G
Ground
N/C
8
Not Connected
N/C
9
Not Connected
N/C
10
Not Connected
N/C
11
Not Connected
N/C
12
Not Connected
PV
13
N
Negative Programming Voltage
PEN
14
I
Programming Enable
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
kPa
bar
mm Hg
PSI
atm
mm H2O
Inches
H2O
400.0
40.00
0.4000
300.0
5.801
0.3947
4079
160.57
1000.0
100.00
1.0000
750.0
14.503
0.9869
10198
401.45
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ABSOLUTE MAXIMUM RATINGS
Parameter
Symbol
Conditions
Min
Max
Unit
Notes
Supply voltage
VDD
-0.3
4
V
Differential Overpressure
Pdiff
-5
5
bar
1, 2
CM Overpressure
PCM
10
bar
1, 3
Storage temperature
TS
-40
+125
°C
1
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 O PERATING CONDITIONS
(Ta = 25 °C, VDD = 3.0 V unless noted otherwise)
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
Supply voltage
VDD
2.2
3.0
3.6
V
Supply current,
average (1)
during conversion (2)
standby (no conversion)
Iavg
Isc
Iss
VDD = 3.0 V
4
1
0.1
µA
mA
µA
Current consumption into MCLK
(3)
MCLK = 32.768 kHz 0.5 µA
Operating pressure range (4)
p
Pressure Range P devices
-400
1000
mbar
Operating pressure range (4)
p
Pressure Range N devices
-1000
400
mbar
Operating temperature range
Ta
-40
+25
+85
°C
Conversion time
tconv
MCLK = 32.768 kHz
35
ms
External clo ck signal (5)
MCLK
30.000
32.768
35.000
kHz
Duty cycle of MCLK
40/60
50/50
60/40
%
Serial data clock
SCLK
500
kHz
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 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 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
DIGITA L INPUTS
(T = -40 °C .. 60 °C, VDD = 2.2 V .. 3.6 V)
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
Input High Voltage
VIH
80% VDD
100% VDD
V
Input Low Voltag e
VIL
0% VDD
20% VDD
V
Signal Rise Time
tr
200
ns
Signal Fall Time
tf
200
ns
DIGITAL OUTPUTS
(T = -40 °C .. 85 °C VDD = 2.2 V .. 3.6 V)
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
Output High Voltage
V
OH
I
source
= 0.6 mA
80% V
DD
100% V
DD
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
(T = -40 °C .. 85 °C VDD = 2.2 V .. 3.6 V)
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
Resolution
16
Bit
Linear Range
4'000
40'000
LSB
Conversion Time
MCLK = 32.768 kHz
35
ms
INL
Within linear rang e
-5
+5
LSB
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PRESSURE OUTPUT CHARACTERISTICS
With the calibration data stored in the interface IC of the MS5536C, the following characteristics can be
achieved: (VDD = 3.0 V unless noted otherwise)
Parameter
Conditions
Min
Typ
Max
Unit
Notes
Resolution
0.1
mbar
1
Pressure Accuracy
T
a
= 10 .. +40°C
MS5536-CPJU: p = -100 .. 700 mbar
MS5536-CNJU: p = -700 .. 100 mbar
-2.5 +2.5 mbar 2
T
a
= 10 .. +40°C
MS5536-CPJU: p = -400 .. 1000 mbar
MS5536-CNJU: p = -1000 .. 400 mbar
-9 +9 mbar 2
Maximum Error over
Temperature Ta = -40 .. +85°C
p = const.
-7 +3 mbar 3
Maximum Error over
Supply Voltage
VDD = 2.2 .. 3.6 V -1.5 0 1.5 mbar 2
NOTES
1) A stable pressure reading of the given resolution requires taking 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 output. Reference temperature is 20 °C. (VDD = 3.0 V unless noted otherwise)
Parameter
Conditions
Min
Typ
Max
Unit
Notes
Resolution
0.01
°C
Accuracy
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
Maximum Error over Supply
Voltage
VDD = 2.2 .. 3.6 V -0.2 0.2 °C 2
NOTES
1) Refer to the paragraph second-order temperature compensation in the section "FUNCTION".
2) ∆p=0
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TYPICAL PERFORMANCE CURVES
s
ADC-value D2 vs Temperature (typical)
15000
20000
25000
30000
35000
40000
45000
50000
-40 -20 020 40 60 80
Temperature (°C)
ADC-value D2 (LSB)
Abso lute Pressure Accuracy af ter Calibration fo r MS5536-CPJU
-4
-2
0
2
4
6
8
10
12
-400 -300 -200 -100 0100 200 300 400 500 600 700 800 900 1000
Pressure (mbar)
Pressure error (mbar)
85°C
60°C
40°C
20°C
0°C
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Temperature Error Accuracy vs temperature (typical)
-5
0
5
10
15
-40 -20 020 40 60 80
Temperat ure (°C)
Temperature error (°C)
Temperature error (st andard
calculation)
Temperature error (with 2nd
order calculati on)
Pressure Error Accuracy vs temperature (typical) for MS5536-CPJU
-8
-6
-4
-2
0
2
4
6
8
10
12
14
16
18
-40 -20 020 40 60 80
Temperature (°C)
Pressure error (mbar)
Perror(600,1st order)
Perror(600,2nd order)
Perror(0,1st order)
Perror(0,2nd order)
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Pressure error vs supply voltage (typical)
-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1
2.2 2.4 2.6 2.8 33.2 3.4 3.6
Voltage (V)
Pressure error (mb ar)
600mbar
0mbar
Temperature error vs supply voltage (typical)
-0.15
-0.1
-0.05
0
0.05
0.1
0.15
2.2 2.4 2.6 2.8 33.2 3.4 3.6
Voltage (V)
Temperature error (°C)
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FUNCTION
GENERAL
The MS5536C consists of a piezo-resistive sensor and a sensor interface IC. The main function of the MS5536C
is to convert the uncompensated analogue output voltage from the piezo-resistive pressure sensor to a 16-bit
digital value, as well as pro vidin g a 16-bit digital value for the temperature of the sensor.
Measured pressure (16-bit) “D1”
Measured temperature (16-bit) “D2”
As the output voltage of a pressure sensor is strongly dependent on temperature and process tolerances, it is
necessar y to compens ate for thes e effect s. This com pensation proce dure m ust be perform ed by soft ware using
an external microcontroller.
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 resistor 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
Every m odule is indi viduall y factor y calibrated at t wo t em peratures and two press ures. As a result, 6 c oeff icients
necessar y to com pens ate for proces s var iations and t em perature var iat ions ar e calc ulate d and stor ed in the 64-
bit 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
pressur e is calcul ated out of D1, D 2 and C1 t o C6 according t o the a lgorithm in Fig. 3 (p ossibl y using q uadratic
temperature compensation according to Fig. 5). All calculations can be performed with signed 16-Bit variables.
Results of multiplications m ay be up to 32-Bit long (+sign). In the flow according to Fig. 3 each multiplication is
Sensor
D1
D2
Word 1..4
Calculation
in external
micro-
controller
Pressure
Temperature
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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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System
initialisation
Pressure and temperature measurement
Example:
Word1, Word2, Word3 and Word4 (4x16 Bit)
D1 = 15832
D2 = 28877
Start
Convert calibration data into coefficients:
(see bit pattern of Word1-Word4)
Read calibration data (factory calibrated) from
PROM of MS5536C
Display pressure and temperature value
Basic equations:
Calculate temper at ure co mpe nsat ed pr es sure
Difference between actual temperature and reference
temperature:
dT = D2 - UT1
Actual tempe ra t ur e:
TEMP = 2000 + dT*(C6+262)/2
9
(weight: 0.01°C)
Calculate actual tem per at ure
SENST1
OFFT1
TCS
TCO
T
ref
TEMPSENS
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)
Word1 = 45834
Word2 = 61787
Word3 = 49110
Word4 = 4060
C1 = 4054
C2 = 4060
C3 = 179
C4 = 241
C5 = 2826
C6 = 91
dT(D2) = D2 - T
ref
TEMP(D2)=20°+dT(D2)*TEMPSENS
Offset at actual temperature:
OFF = C2 +10381+ ((C4-243)*dT)/2
12
Sensitivity at actual temperature:
SENS = C1 + 10179+((C3+222)*dT)/2
11
X = (SENS * (D1-OFF))/2
12
Temperature compensated pressure:
P = 2X (weight: 0.01mmHg)
P = X*1365/2
9
(weight: 0.01mbar)
OFF(D2)=OFFT1+TCO*dT(D2)
SENS(D2)=SENST1+TCS*dT(D2)
P(D1,D2)= SE NS(D2)*(D1- OFF(D2))
dT = 2437
TEMP = 3680
= 36.80 °C
OFF = 14440
SENS = 14710
X = 4999
P = 9998
= 99.98 mmHg
UT1= 26440
Read digital pressure value from MS5536C
D1 (16 Bit)
Calculate calibr at io n temper at ur e
UT1=4*C5+15136
Read digital temperature value from MS5536C
D2 (16 Bit)
Fig. 3: Flow chart for pressure and 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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C3/II (8-Bit)
C5/II(8-Bit)
Word 1 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
C4/II (8-Bit)
C6(8-Bit)
Word 2 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
C5/I (4-Bit)
C1/II (12-Bit)
Word 3 DB11 DB10 DB9 DB8 DB11 DB10 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
C1/I
C4/I
C3/I
C2 (13-Bit)
Word 4 DB12 DB8 DB8 DB12 DB11 DB10 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
Fig. 4: Arrangement (Bit-pattern) of calibrat ion 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:
Calculate actual temperature
Difference between the actual temperature and
reference temperature:
dT = (D2 - UT1) - ((D2-UT1)*(D2-UT1))/2
18
Actual temperature in °C
TEMP = 2000 + dT*(C6+262)/2
9
(weight: 0.01° C)
Calculate actual temperature
Difference between the actual temperature and
reference temperature:
dT = (D2 - UT1) - (9*(D2-UT1)*(D2-UT1))/2
18
Actual temperature in °C
TEMP = 2000 + dT*(C6+262)/2
9
(weight: 0.01° C)
D2≥UT1?
no
yes
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 trans fer with each Bit being sam pled b y the MS5536C o n the risin g edge of SCL K and each Bit being s ent
by the MS5536C on the rising edge of SCLK. The data should thus be sampled by the microcontroller on the
falling edg e of SCLK and s ent to the M S5536C with the f alling edge of SCLK. T he SCLK-s ignal is gen erated 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 convers ion status ( conversion-r eady signa l, see below). T he selection of the output d ata is done b y 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 “D1” (Figure 6a)
• Conversion start for temperature measurement and ADC-data-out “D2” (Figure 6b)
• Calibration data read-out sequence for word 1 and word 3 (Figure 6c)
• Calibration data read-out sequence for word 2 and word 4 (Figure 6d)
• RESET sequence (Figure 6e)
Every communication starts with an instruction sequence at Pin DIN. Fig. 6 shows the timing diagrams for the
MS5536C. T he device doe s not need a ‘ Chi p s elect ’ s igna l. Instead there is a S tart Sequenc e ( 3-B it high) bef ore
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 m icrocontroller m ay now read out the
16-Bit word by giving another 17 clock s on the SLCK pin. It is possible to interrupt the data read-out sequence
with a hol d of the SCLK s ignal. It is important to always read out the last conversion result before starting
a new conversion.
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. T his s equence is 21-Bit long. T he DO UT signal m ight chang e during t hat sequenc e (see F ig. 6e). I t is
recom mended to send the RESET sequence before f irst conversion sequ ence to avoid hanging up the pr otocol
permanently in case of el ec tric al interf erenc e.
sequence: START+P-measurement
SCLKDOUTDIN
Bit7
Conversion start for pressure measurement and ADC-data-out "D1":
end of conversion
Bit6Bit5Bit4Bit3Bit2Bit1Bit0
conversion
(33ms)
DB7
ADC-data ou t MSB ADC-dat a out LSB
Bit8 Bit9
Start-bit Stop-bit
DB6 DB5 DB4 DB3 DB2 DB1 DB0 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
start of conversion
Setup-bits
Fig. 6a: D1 ACQUISITION sequence
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sequence: START+T-measurement
SCLK
DOUT
DIN
Bit7
Conversion start for temperature measurement and ADC-data-out "D2":
end of conversion
Bit6Bit5Bit4Bit3Bit2Bit1Bit0
conversion
(33ms)
Bit8 Bit9
Start-bit Stop-bit
Setup-bits
start of conversion
DB7
ADC-data ou t MSB ADC-dat a out LSB
DB6 DB5 DB4 DB3 DB2 DB1 DB0 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
Fig. 6b: D2 ACQUISITION sequence
sequence: coefficient read + address
SCLK
DOUTDIN
Bit7
Calibration data read out sequence for word 1/ word 3:
Bit6Bit5Bit4Bit3Bit2Bit1Bit0
DB7
coefficient-dat a out MSB coefficient-data out LSB
Bit8 Bit9
Start-bit Stop-bit
DB6 DB5 DB4 DB3 DB2 DB1 DB0 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
Bit10 Bit11
address word 1
address word 3
Setup-bits
Fig. 6c: Word1, Word3 READING sequence
address word 2
address word 4
sequence: coefficient read + address
SCLK
DOUT
DIN
Bit7
Calibration data read out sequence for word 2/ word 4:
Bit6Bit5Bit4Bit3Bit2Bit1Bit0
DB7
coefficient-dat a out MSB coefficient-data out LSB
Bit8 Bit9
Start-bit Stop-bit
DB6 DB5 DB4 DB3 DB2 DB1 DB0 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
Bit10 Bit11
Setup-bits
Fig. 6d: W2, W4 READING sequence
sequence: RESET
SCLKDOUTDIN
Bit7
RESET - sequence:
Bit6Bit5Bit4Bit3Bit2Bit1Bit0 Bit8 Bit9 Bit10 Bit11Bit12 Bit13 Bit14 Bit15 Bit16 Bit17 Bit18 Bit19 Bit20
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 com patible with standard PCB-assembly technologies (Pick and Place followed b y IR-
reflow soldering). Single sided PCB layout is possible. The device directly interfaces to a standard
microc ontroller, n o costl y external component s like I nstrum entation Am plifiers or A/D conv erters ar e requir ed. 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 sim ple digital 3 wire s ynchronous 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 implem ented on an y micr ocontroller us ing standar d I/Os. T he required exter nal clock -signal of 32.768 k Hz is
standard in the watch ind us try and readily availa ble in most hand-held applications.
The MS5536C is wel l suited for batter y powered porta ble devices. T his is due to the low suppl y 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
applicat ion sof t ware. This c an be achi ev ed by readi ng the c ompensated pr ess ur e in a k no wn state, pref erabl y 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 pres sure range and port conf igurations m ake the MS5 536C well su ited for appl ications lik e bloo d-pressure
metering, air flow and pressure measurements in HVAC-systems and liquid level detection.
4/8bit-Microcontroller
LCD-Display
EEPROM
Keypad
MS5536C
SCLK
DIN
DOUT
MCLK
XTAL1
XTAL2
32.768 kHz
optional
VDD
GND
VDD
GND
3V-Battery
47µF
Tantal
Fig. 7: Application example of the MS5536C for a battery powered device
MS5536C SMD Gage Pressure Module
DA5536C_005 www.meas-spec.com Jun. 27, 2011
0005536C1245 ECN1511 16/18
DEVICE PACKAGE OUTLINES
All dimension s in mm
Fig. 8: Device package outlines of MS5536-CPJU / MS5536-CNJU
PAD LAYOUT FOR MS5536-C
All dimensions in mm [inch]
Fig. 9: Recom men ded pad-layout for MS5536-CPJU / MS5536-CNJU
10.8 [0.425]
1.3 [0.051]
0.7 [0.028]
1.27 [0.050]
MS5536C SMD Gage Pressure Module
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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 hi ghes t poss ib l e accur acy.
SOLDERING
Please refer to the application note AN808 for all soldering issues.
MOUNTING
The MS553 6C c an be p lac ed with aut omatic Pick&Pla c e equi pment using a spec i al vac uum nozzle. It w ill 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 produc t th e s ens or c a nnot be ex p os ed t o d ir ect
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 cle an. The tube sh ould be f lexible enoug h to
minim ize the m echanical str ess on the module (s ee
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 und er c lass 10 ’0 00 or b et ter c o nd iti ons. Sho uld this not be p os s ible, it i s rec ommended to pr otect t he
sensor ope ning dur ing as sem bl y from enter ing partic les and dus t. To av oid clea ning of the PCB , sol der pas te of
type ‘No-Clean’ shall be used.
CLEANING MIGHT DAMAGE THE SENSOR!
MS5536C SMD Gage Pressure Module
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0005536C1245 ECN1511 18/18
ESD PRECAUTIONS
The electrical contact pads are protected against ESD up to 4 kV HBM (human body model). It is therefore
essentia l to groun d machin es and p ers onal pr o perly dur ing ass embl y and han dl in g 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.
ORDERING INFORMATION
Product Code
Product
Art. No
Package
Comments
MS5536-CPJU SMD Gage
Pressure Module
RoHS 325536008 Gage with plastic cap, upright
nozzle, vent hole on backside,
J-Lead type
Pressure Range
(port1 – port2):
-400 mbar …+1000 mbar
MS5536-CNJU SMD Gage
Pressure Module
RoHS 325536009 Gage with plasti c cap, upri ght
nozzle, vent hole on backside,
J-Lead type
Pressure Range
(port1 – port2):
-1000 mbar …+400 mbar
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The information in this sheet has been carefull y reviewed and is believed to be accurate; however, no responsibilit y is assumed for
inaccuracies. Furtherm ore, this inform ation does not convey to the purchaser of such devices any license under the patent rights to the
manufacturer. Measurem ent Specialt i es, Inc. reserves the right t o make changes without furt her notice to any product herein. Measurement
Specialti es, Inc. makes no warranty, represent ation or guarant ee regarding the sui t abili t y of its product for any particular purpose, nor does
Measurement Specialti es, Inc. assume any liability arising out of the application or use of any product or circuit and specifica lly d is cl a ims
any and all liabilit y, includi ng without limitation consequential or incidental damages. Typical paramet ers can and do vary in different
applicat i ons. All operat i ng parameters must be validated for each customer application by customer’s technic al experts. Meas urem ent
Specialti es, Inc. does not convey any license under its patent rights nor the rights of others.
