MS5561C Micro Altimeter
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0005561C1126 ECN1405 1/20
• 10 - 1100 mbar / 1 – 110 kPa absolute pressure range
• High accuracy temperature measurement
• Integrated miniature pressure sensor 4.75 x 4.25 mm
• Thin design of 1.6 mm
• Piezoresistive silicon micromachined sensor
• 6 coeffi cients for software compensation stored on-chip
• 16 Bit A DC, sigma delta converter
• 3-wire serial interface
• 1 system clock line (32.768 kHz)
• Low voltage and low power consumption
DESCRIPTION
The MS5561C is a SMD-hybrid device including a precision piezo-resistive pressure sensor and an ADC-
Interfac e IC. It uses a thre e-wire serial interf ace for comm unication. The m odule dimens ions of 4.75 mm x 4.25
mm and a height of only 1.6 mm allows for up-to-date SMD design. It provides a 16 bit data word from a
pressur e and temperature dependent voltage . The MS5561C is a low p ower, low voltag e device with aut omatic
power down (ON/OFF) switching. A 3-wire interface is used for all communications with a micro-controller.
FEATURES APPLICATIONS
•
Pressure resolution 0.1 mbar
•
Mobile phones
•
Operating temperature -40°C to +85°C
•
GPS receivers
•
Supply voltage 2.2 V to 3.6 V
•
Altimeter applications
• Low supply current, typ. 4 µA • Personal Navigation Devices (PND)
•
Standby current < 0.1 µA
•
Digital cameras with altimeter function
• Calibrated temperature and pressure sensor for
2
nd
order compensation
•
ESD protected, HBM 4 kV
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: B lock diagr am MS5561C
MS5561C Micro Altimeter
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PIN CONFIGURATION
Fig. 2: Pin configuration of MS5561C
Pin Name
Pin
Type
Function
SCLK
1
I
Serial data cloc k
GND
2
G
Ground
PV (1)
3
N
Negative programming voltage
PEN (1)
4
I
Programming enable
VDD
5
P
Positive supply voltage
MCLK
6
I
Master clock (32.768 kHz)
DIN
7
I
Serial data input
DOUT
8
O
Serial data output
NOTE
1) Pin 3 (PV) and Pin 4 (PEN) are only used by the manufacturer for calibration purposes and should not be
connected.
ABSOLUTE MAX IMUM RATINGS
Parameter
Symbol
Conditions
Min
Max
Unit
Notes
Supply voltage
VDD
Ta = 25 °C
-0.3
4
V
Storage temperature
TS
-40
+85
°C
1
Overpressure
P
Ta = 25 °C
5
bar
NOTE
1) Storage and operation in an environment of dry and non-corrosive gases.
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RECOMMENDED O PERATING CONDITIONS
(Ta = 25 °C, VDD = 3.0 V unless noted otherwise)
Parameter
Symbol
Conditions
Min
Typ
Max
Unit
Operating pressure range p 10 1100
mbar
abs.
Supply voltage
VDD
2.2
3.0
3.6
V
Supply current,
average (1)
during conversion (2)
standby (no conversion)
Iavg
Isc
Iss
V
DD
= 3.0 V
4
1
0.1
µA
mA
µA
Current consumption into MCLK
(3)
MCLK = 32.768 kHz 0.5 µA
Operating temperature range
T
-40
+25
+85
°C
Conversion time
tconv
MCLK = 32.768 kHz
35
ms
External clo ck signal (4)
MCLK
30.000
32.768
35.000
kHz
Duty cycle of MCLK
40/60
50/50
60/40
%
Serial data cloc k
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 MS5561C.
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.
3) This value can be reduced by switching off MCLK while MS5561C is in standby mode.
4) It is strongly recommended that a cry stal 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
(T = -40 °C .. 85 °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 MS5561C, the following characteristics can be
achieved: (VDD = 3.0 V unless noted otherwise)
Parameter
Conditions
Min
Typ
Max
Unit
Notes
Resolution
p = 300 .. 1000 mbar
Ta = 25°C
0.1 mbar 1
Absolute Pressure Accuracy
p = 750 .. 1100 mbar
Ta = 25°C
-1.5 +1.5 mbar 2
Relative Pressure Accuracy
p = 750 .. 1100 mbar
Ta = 25°C
-0.5 +0.5 mbar 3
Relative Pressure Error over
Temperature
T = 0 .. +50°C
p = 300 .. 1000 mbar
-1 +1 mbar 4
T = -40 .. +85°C
p = 300 .. 1000 mbar
-2 +5 mbar 4
Long-term Stability
12 months
-1
mbar
5
Maximum Error over Supply
Voltage
V
DD
= 2.2 .. 3.6 V
p = const.
-1.6 1.6 mbar
NOTES
1) A stable pressure reading of the given resolution requires taking the average of 2 to 4 subsequent pressure
values due to noise of the ADC.
2) Maximum error of pressure reading over the pressure range.
3) Maximum error of pressure reading over the pressure range after offset adjustment at one pressure point.
4) With the second-order temperature compensation as described in Section "FUNCTION". See next section
for typical operating curves.
5) The long-term stability is measured with non-soldered devices .
TEMPERATURE OUTPUT CHARACTERISTICS
This temperature information is not required for most applications, but it is necessary to allow for temperature
compensation of the output. (VDD = 3.0 V unless noted otherwise)
Parameter
Conditions
Min
Typ
Max
Unit
Notes
Resolution
0.005
0.01
0.015
°C
Accuracy
T = 20 °C
-0.8
0.8
°C
T = -40 .. + 85°C
-2
+3
°C
1
Maximum Error over Supply
Voltage
VDD = 2 .2 .. 3.6 V -0.2 +0.2 °C 2
NOTES
1) With the second-order temperature compensation as described in Section "FUNCTION". See next section
for typical operating curves.
2) At Ta = 25 °C.
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TYPICAL PERFORMANCE CURVES
ADC-value D1 vs Pressure (typical)
6000
8000
10000
12000
14000
16000
18000
20000
22000
0100 200 300 400 500 600 700 800 900 1000 1100
Pressure (mbar)
ADC-value D1 (LSB)
-40°C
25°C
85°C
ADC -value D2 vs Temperature (t ypical)
15000
20000
25000
30000
35000
40000
-40 -20 020 40 60 80
Temperature (°C)
ADC-value D2 (LSB)
Abso lute Pressure Accuracy after Calib ration, 2nd order compensation
-4
-3
-2
-1
0
1
2
3
4
0100 200 300 400 500 600 700 800 900 1000 1100
Pressure (mbar)
Pressure error (mbar)
85°C
60°C
25°C
0°C
-40°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)
-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(1000,1st order)
Perror(1000,2nd order)
Perror(800,1st order)
Perror(800,2nd order)
Perror(300,1st order)
Perror(300,2nd 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)
1000mbar
800mbar
300mbar
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 MS5561C consists of a piezo-resistive sensor and a sensor interface IC. The main function of the MS5561C
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 mus t be perform ed by software us ing
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 Fig. 3 and Fig. 5.
First Word1 to Word4 have to be read through the serial interface. This can be done once after reset of the
microcontroller that interfaces to the MS5561C. 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 Word1 to Word4).
For the pressure measurement, the microcontroller has to read the 16-bit values for pressure (D1) and
temper ature (D2) via the ser ial interface in a loo p (for instance ev ery second). T hen, the com pensated pres sure
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 m ultiplicat ions m ay be u p to 32-b it lon g (+si gn). In the f low accor ding to F ig. 3 a divis ion f ollows e ach
Sensor
D1
D2
Word 1..4
Calculation
in external
micro-
controller
Pressure
Temperature
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multiplication. 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 = 16460
D2 = 27856
Start
Convert calibration data into coefficients:
(see bit pattern of W ord1-Word4)
Read calibration data (factory calibrated) from
PROM of MS5561C
Read digital pressure value from MS5561C
D1 (16 Bit)
Read digital temperature value from MS5561C
Display pressure and temperature value
Basic equations:
Calculate calibration temperature
UT1 = 8*C5+20224
Calculate tem perat ur e co mpensated pressure
Difference between actual temperature and reference
temperature:
dT = D2 - UT1
Actual tem pe ra tur e:
TEMP = 200 + dT*(C6+50)/2
10
(0.1°C resolution)
Calculate act ual tem perat ur e
D2 (16 Bit)
SENST1
OFFT1
TCS
TCO
T
ref
TEMPSENS
C1: Pressure sensitivity (15 Bit)
C2: Pressure offset (12 Bit)
C3: Temperature coefficient of pressure sensitivity (10 Bit)
C4: Temperature coefficient of pressure offset (10 Bit)
C5: Reference Temperature (11 Bit)
C6: Temperature coefficient of the temperature (6 Bit)
Word1 = 46940
Word2 = 40217
Word3 = 25172
Word4 = 47212
C1 = 23470
C2 = 1324
C3 = 737
C4 = 393
C5 = 628
C6 = 25
dT(D2) = D2 - T
ref
TEMP(D2) = 20°+dT(D2)*TEMPSENS
Offset at actual temperature:
OFF = C2*4 + ((C4-512)*dT)/2
12
Sensitivity at actual temperature:
SENS = C1 + (C3*dT)/2
10
+ 24576
X = (SENS * (D1-7168))/2
14
- OFF
Temperature compensated pressure:
P = X*10/2
5
+ 250*10 (0.1 mbar resolution)
OFF(D2) = OFFT1+TCO*dT(D2)
SENS(D2) = SENST1+TCS*dT(D2)
P(D1,D2) = D1*SENS(D2)-OFF(D2)
dT = 2608
TEMP = 391
= 39.1 °C
OFF = 5220
SENS = 49923
X = 23093
P = 9716
= 971.6 mbar
UT1 = 25248
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 1 mbar resolution, it is recommended to display the average of 8 subsequent
pressure values.
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C1 (15 Bit)
C5/I
1 Bit
Word1 DB14 DB13 DB12 DB11 DB10 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 DB10
C5/II (10 Bit)
C6 (6 Bit)
Word2 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 DB5 DB4 DB3 DB2 DB1 DB0
C4 (10 Bit)
C2/I (6 Bit)
Word3 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 DB11 DB10 DB9 DB8 DB7 DB6
C3 (10 Bit)
C2/II (6-Bit)
Word4 DB9 DB8 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0 DB5 DB4 DB3 DB2 DB1 DB0
Fig. 4: Arrangement (Bit-patter n) of calibration data in Word1 to Word4
SECOND-ORDER TEMPERATURE COMPENSATION
In order to obtain full temperature accuracy over the whole temperature range, it is recommended to
compens ate f or the n on-l inear ity of the outp ut of the t e mperature s ens or. T his can be ac hi ev ed by correcting the
calculated temperature and pressure by a second order correction factor. The second-order factors are
calculated as follows:
No correction
T2 = 0
P2 = 0
High Temperatures
T2 = 3*(C6+24)*(450 - TEMP)*(450 – TEMP) / 2
20
P2 = T2 * (P - 10000)/2
13
TEMP < 200
yes
Calculate pressure and temperature
TEMP = TEMP – T2
P = P – P2
Low Temperatures
T2 = 11*(C6+24)*(200 - TEMP)*(200 – TEMP) / 2
20
P2 = 3 *T2 * (P - 3500)/2
14
TEMP > 450
yes
200 ≤ TEMP ≤ 450
yes
Fig. 5: Flow chart for calculating the temperature and pressure to the optimum accuracy.
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SERIAL INTERFACE
The MS5561C 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 bei ng sampled b y the MS5561C on the r ising edge of SCL K and each bit bein g sent
by the MS5561C 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 MS5561C with th e fallin g edge of SCL K. The SCLK -signal is gen erate d b y
the microprocessor’s system. The digital data provided by the MS5561C 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 t he conversi on status (conversion-r eady signa l, see belo w). The selec tion of the output dat a is do ne 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 Word1 (Figure 6c)
• Calibration data read-out sequence for Word2 (Figure 6d)
• Calibration data read-out sequence for Word3 (Figure 6c)
• Calibration data read-out sequence for Word4 (Figure 6d)
• RESET sequence (Figure 6e)
Every communication starts with an instruction sequence at pin DIN. Fig. 6 shows the timing diagrams for the
MS5561C. 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 temperat ure- (D2) r ead ing t h e module ack no wledges t he s t art o f a conversi on by a low t o h igh
transition at pin DOUT.
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. T he microcontroller may now read out the
16 bit word b y giving a not h er 17 cloc ks on the SLCK pin. It is poss ib le to i nterr up t the dat a R EADOUT s equence
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 the module in any state recognizes its unique pattern. By consequence, it
can be used to restart if synchronization between the microcontroller and the MS5561C has been lost. This
sequence is 21-bit long. T he DOUT signal m ight change duri ng that seq uence (s ee Fig. 6e). It is rec ommended
to send the RESET sequence before each CONVERSION sequence to avoid hanging up the protocol
permanently in case of electrical interference.
sequence: START+P-measurement
SCLKDOUTDIN
Bit7
Conversion start for pressure measurement and ADC-data-out "D1":
end of co nve rsion
Bit6Bit5Bit4Bit3Bit2Bit1Bit0
conversion
(33ms)
DB7
ADC-data ou t MSB ADC-data o u t 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 co nve rsion
Bit6Bit5Bit4Bit3Bit2Bit1Bit0
conversion
(33ms)
Bit8 Bit9
Start-bit Stop-bitSetup-bits
start of conversion
DB7
ADC-data ou t MSB ADC-data o u t LSB
DB6 DB5 DB4 DB3 DB2 DB1 DB0 DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
Fig. 6b: D2 ACQUISITION sequence
sequence: coefficient r ead + add r ess
SCLKDOUTDIN
Bit7
Calibration data read out sequence for word 1/ word 3:
Bit6Bit5Bit4Bit3Bit2Bit1Bit0
DB7
coefficient- d ata 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 r ead + add r ess
SCLK
DOUT
DIN
Bit7
Calibration data read out sequence for word 2/ word 4:
Bit6Bit5Bit4Bit3Bit2Bit1Bit0
DB7
coefficient- d ata 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 seq uenc e
sequence: RESET
SCLK
DOUT
DIN
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 advantage of combining a pressure sensor with a directly adapted integrated circuit is to save other external
components and to achieve very low power consumption. The main application field for this system includes
portable devices with battery supply, but its high accuracy and resolution make it also suited for industrial and
automotive applications. The possibility to compensate the sensor by software allows the user to adapt it to his
particular application. Communication between the MS5561C and the widely available microcontrollers is
realized over an easy-to-use 3-wire serial interface. Customers may select which microcontroller system to be
used, and ther e are no spe cif ic standard inter face c ells r equired, wh ich m ay be of interes t for spec ially desig ned
4 bit-microcontroller applications. For communication via SPI interface please refer to application note AN510
that may be downloaded from the MEAS Swit zerla nd website.
CALIBRATION
The MS5561C is factory calibrated. The calibration data is stored inside the 64 bit PROM memory.
SOLDERING
Please refer to the application note AN808 for all soldering issues.
HUMIDITY, WATER PROTECTION
This module is designed for the integration into portable devices and sufficiently protected against humidity. A
silicone gel for enhanced protection against humidity covers the membrane of the pressure transducer.
The module must not be used for under water applications.
LIGHT SENSITIVITY
The MS5561C is protected against sunlight by a layer of white gel. It is, however, important to note that the
sensor may still be slightly sensitive to sunlight, especially to infrared light sources. 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.
DECOUPLING CAPACITOR
Particular c ar e must be tak en wh en connecting the de vice t o p o wer sup ply. A 47 µF tanta lum capacitor must be
placed as close as possible of the MS5561C's VDD pin. This capacitor will stabilize the power supply during
data conversion and thus, prov ide the highes t pos s ibl e acc uracy.
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APPLI CATION EXAM PLE: ALTIMETER SYSTEM USING MS5561C
MS5561C is a cir cuit that c an be used in c onnection with a microcont roller in mobile altimeter applicat ions. It is
designed for lo w-voltage s ystem s with a sup pl y voltage of 3V, p articu larl y in batt er y applic ations. T he MS5561C
is optim ised for low current consumption as the AD -converter clock (MCLK) can use the 32.768 kH z frequency
of a standard watch crystal, which is supplied in most portable watch systems.
For applications in altimeter systems MEAS Switzerland can deliver a simple formula to calculate the altitude,
based on a linear interpolation, where the number of interpolation points influences the accuracy of the formul a.
Figure 7: Demonstration of MS5561C in a mobile altimeter
RECOMMENDED PAD LAYOUT
Pad layout for bottom side of MS5561C soldered onto printed circuit board.
Microcontroller
LCD-Display
EEPROM
Keypad
MS5561C
SCLK
DIN
DOUT
MCLK
XTAL1
XTAL2
32.768 kHz
optional
VDD
GND
VDD
GND
3V-Battery
47uF
Tantal
MS5561C Micro Altimeter
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DEVICE PACKAGE OUTLINES
Fig. 8: Device package outlines of MS5561-C
MS5561C Micro Altimeter
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ASSEMBLY
MOUNTING
The MS5561C can be placed with automatic Pick&Place equipment using vacuum nozzles. It will not be
damaged by the vacuum. Due to the low stress assembly the sensor does not show pressure hysteresis effects.
It is important to solder all contact pads to avoid floating of the sensor during soldering. The pins PEN and PV
shall be left open or connected to VDD. Do not connect the pins PEN and PV to GND!
CLEANING
The MS5561C has been manufactured under cleanroom conditions. Each device has been inspected for the
homogeneity and the cleanness of the silicone gel. 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 ass embl y from entering p articles and d ust. To avo id cleani ng of the PCB , solder pas te of type “no-clean”
shall be used. Cleaning might damage the sensor!
ESD PRECAUTIONS
The electrical contacts except programming pads are protected against ESD up to 4 kV HBM (human body
model) . The MS5561C 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.
MS5561C Micro Altimeter
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SHIPPING PAC KA GE
Tape
Units per reel 4’000 Minimum empty leader
(right side of draw ing)
250 mm
Tape widths
12 mm
Minimum empty trailer
(left side of draw ing,
direction of unreelin g)
250 mm
Tape material
Black Conductive Polystyrene
Reel diameter
13” / 330 mm
Fig, 9: Outline of tape for MS5561C
Fig.10: Outline of reel for MS5561C
MS5561C Micro Altimeter
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ORDERING INFORMATION
Product Code
Product
Art. No
Package
Comments
MS5561-C Micro Altimeter 325561000 Small Size SMD with metal lid Module height 1.6 mm
FACTORY CONTACTS
NORTH AMERICA EUROPE ASIA
Measurement Specialties
45738 Northport Loop West
Fremont, CA 94538
Tel: +1 800 767 1888
Fax: +1 510 498 1578
e-mail: pfg.cs.amerameas-spec.com
Website: www.meas-spec.com
MEAS Switzerland Sàrl
Ch. Chapons-des-Prés 11
CH-2022 Bevaix
Tel: +41 32 847 9550
Fax: + 41 32 847 9569
e-mail: sales.chameas-spec.com
Website: www.meas-spec.com
Measurement Specialties (China), Ltd.
No. 26 Langshan Road
Shenzhen High-Tech Park (North)
Nanshan District, Shenzhen, 518057
China
Tel: +86 755 3330 5088
Fax: +86 755 3330 5099
e-mail: pfg.cs.asiaameas-spec.com
Website: www.meas-spec.com
The information in this sheet has been carefull y reviewed and is believed to be accurate; however, no responsibil i ty 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. Meas urem ent
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 applic at i on or use of any product or circuit and specifically disclaims
any and all liabilit y, includi ng without limitation consequential or incidental damages. Typical parameters can and do vary in different
applicat i ons. All operat i ng parameters must be validated for each customer appl ic ation by customer’s tec hni c al experts. Measurem ent
Specialti es, Inc. does not convey any license under its patent rights nor the rights of others.
