MLX90632 FIR sensor
Datasheet
Features and Benefits
Small size
Easy to integrate
Factory calibrated
External ambient and object temperature
calculation
Standard measurement resolution 0.02°C
Medical measurement resolution 0.01°C
Supply voltage of 3.3V, supply current
1mA (sleep current less than 2.5uA)
I2C compatible digital interface
Software definable I2C address with 1 LSB
bit external address pin
Field of View of 50°
Default refresh rate 0.5s, configurable
between 16ms and 2s
Integrated post-calibration option
Application Examples
High precision non-contact temperature
measurements
Body temperature measurement
Non-contact thermometer for mobile and
IoT application
Temperature sensing element for
residential, commercial and industrial
building air conditioning
Industrial temperature control of moving
parts
Home appliances with temperature
control
Healthcare
Livestock monitoring
https://github.com/melexis/mlx90632-
library
Figure 1: Image of MLX90632
MLX90632 FIR sensor
Datasheet
Description
The MLX90632 is a non-contact infrared temperature sensor in a small SMD SFN package. The device is factory
calibrated with calibration constants stored in the EEPROM memory. The ambient and object temperature can
be calculated externally based on these calibration constants and the measurement data.
The MLX90632 is available in two different versions: standard and medical accuracy.
Both versions are calibrated in the ambient temperature range from -20 to 85˚C.
The difference between both versions is visible in accuracy and the object temperature range.
The medical version is factory calibrated with an accuracy of ±0.2˚C within the narrow object temperature range
from 35 to 42˚C for medical applications. The object temperature range is limited from -20 to 100˚C.
On the other hand, the standard version covers an object temperature range from -20 to 200˚C but offers an
accuracy of ±1˚C.
It is very important for the application designer to understand that these accuracies are guaranteed and
achievable when the sensor is in thermal equilibrium and under isothermal conditions (no temperature
differences across the sensor package).
The accuracy of the thermometer can be influenced by temperature differences in the package induced by
causes like (among others): Hot electronics behind the sensor, heaters/coolers behind or beside the sensor or by
a hot/cold object very close to the sensor that not only heats the sensing element in the thermometer but also
the thermometer package.
A major strength of the MLX90632 is that these temperature differences around the sensor package will be
reduced to the minimum.
However, some extreme cases will influence the sensor.
In the same way, localized thermal variations -like turbulence in the air- will not generate thermal noise in the
output signal of the thermopile.
The typical supply voltage of the MLX90632 is 3.3V. For the I2C communication with the master microcontroller,
two versions of the sensor are available, working either at 3.3V or 1.8V I2C reference voltage.
The communication to the chip is done by I2C in fast mode plus (FM+).
Through I2C the external microcontroller has access to the following blocks:
RAM memory used for measurement data, in this document mainly referred to as ‘storage memory’
EEPROM used to store the trimming values, calibration constants and device/measurement settings
Based on this data, the external microcontroller can calculate the object temperature and if needed the sensor
temperature.
An optical filter (long-wave pass) that cuts off the visible and near infra-red radiant flux is integrated in the sensor
to provide ambient light immunity. The wavelength pass band of this optical filter is from 2 till 14µm.
MLX90632 FIR sensor
Datasheet
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REVISION 9 – MAY, 2020
Contents
Features and Benefits ................................................................................................................................ 1
Application Examples ................................................................................................................................ 1
Description ................................................................................................................................................ 2
Ordering Information ............................................................................................................................ 5
2.
Glossary of Terms .................................................................................................................................. 6
3.
Absolute Maximum ratings .................................................................................................................... 7
4.
Pin definitions and descriptions ............................................................................................................. 8
5.
Electrical characteristics ........................................................................................................................ 9
6.
Detailed General Description ............................................................................................................... 10
7.
Block diagram .................................................................................................................................... 10
7.1.
Description ........................................................................................................................................ 10
7.2.
Memory map ....................................................................................................................................... 11
8.
Product ID .......................................................................................................................................... 14
8.1.
Product Code (0x2409) ..................................................................................................................... 15
8.2.
Control and configuration .................................................................................................................... 16
9.
Measurement control ....................................................................................................................... 16
9.1.
Device status ..................................................................................................................................... 18
9.2.
Measurement settings...................................................................................................................... 19
9.3.
9.3.1. Refresh rate ................................................................................................................................. 19
I2C commands ................................................................................................................................... 20
10.
I2C address....................................................................................................................................... 21
10.1.
Addressed read ............................................................................................................................... 22
10.2.
Addressed write .............................................................................................................................. 22
10.3.
Global reset ..................................................................................................................................... 23
10.4.
Addressed reset .............................................................................................................................. 23
10.5.
EEPROM unlock for customer access ............................................................................................ 23
10.6.
Direct read ...................................................................................................................................... 24
10.7.
Operating Modes ............................................................................................................................... 25
11.
Temperature calculation ................................................................................................................... 26
12.
Medical measurement ................................................................................................................... 26
12.1.
12.1.1. Pre-calculations ........................................................................................................................ 27
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12.1.2. Ambient temperature .............................................................................................................. 28
12.1.3. Object temperature ................................................................................................................. 28
12.1.4. Example Medical measurement Temperature Calculation .................................................... 29
Extended range measurement ...................................................................................................... 33
12.2.
12.2.1. Pre-calculations ........................................................................................................................ 33
12.2.2. Ambient temperature .............................................................................................................. 34
12.2.3. Object temperature ................................................................................................................. 34
12.2.4. Example Extended range measurement Temperature Calculation ....................................... 36
Performance characteristics .............................................................................................................. 40
13.
Accuracy .......................................................................................................................................... 40
13.1.
13.1.1. Standard .................................................................................................................................... 40
13.1.2. Medical ...................................................................................................................................... 41
Field of View (FoV) .......................................................................................................................... 42
13.2.
Noise ................................................................................................................................................ 43
13.3.
Mechanical Drawing .......................................................................................................................... 44
14.
Package dimensions ....................................................................................................................... 44
14.1.
PCB footprint ................................................................................................................................... 45
14.2.
Application schematic........................................................................................................................ 46
15.
3V3 I2C mode .................................................................................................................................. 46
15.1.
1V8 I2C mode .................................................................................................................................. 47
15.2.
Software ............................................................................................................................................ 48
16.
Standard information regarding manufacturability of Melexis products with different soldering 17.
processes ............................................................................................................................................ 49
ESD Precautions ................................................................................................................................. 50
18.
Application comments ....................................................................................................................... 50
19.
Table of figures .................................................................................................................................. 51
20.
Disclaimer .......................................................................................................................................... 52
21.
Contact Information .......................................................................................................................... 53
22.
MLX90632 FIR sensor
Datasheet
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Ordering Information 2.
Product Temperature Code Package Option Code Packing Form
MLX90632
S
LD
BCB-000
RE
MLX90632
S
LD
DCB-000
RE
MLX90632
S
LD
DCB-100
RE
Table 1 : Ordering codes for MLX90632
Legend:
Temperature Code: S: from -20°C to 85°C sensor temperature
Package Code: “LD” for SFN 3x3 package
Option Code:
XYZ-123
X: Accuracy
B: Standard accuracy
D: Medical accuracy
Y: Pixel type
C: High stability version
Z: Field Of View
B: 50 degrees
1: I2C level
0: 3V3
1: 1V8
2-3:
00: Standard configuration
xx: Reserved
Packing Form: “RE” for Reel
Ordering Example: “MLX90632SLD-DCB-000-RE”
For a FIR Sensor type in SFN 3x3 package with medical accuracy, Field Of View of
50 degrees and 3V3 I2C level, delivered in Reel.
Table 2: Coding legend
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Datasheet
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Glossary of Terms 3.
POR Power On Reset
IR InfraRed
I2C Inter-Integrated Circuit
SDA Serial DAta – I2C compatible communication pins
SCL Serial CLock – I2C compatible communication pins
ACK / NACK Acknowledge / Not Acknowledge
SOC Start Of Conversion
EOC End Of Conversion
FOV Field Of View
Ta Ambient Temperature measured from the chip – (the package temperature)
To Object Temperature, ‘seen’ from IR sensor
SFN Single Flat pack No-lead
TBD To Be Defined
LSB Least Significant Bit
MSB Most Significant Bit
EMC Electro-Magnetic Compatibility
ESD Electro-Static Discharge
HBM Human Body Model
CDM Charged Device Model
Table 3: List of abbreviations
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Datasheet
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Absolute Maximum ratings 4.
Parameter Symbol Min. Typ. Max. Unit
Supply Voltage, (over voltage) VDD 5 V
Supply Voltage, (operating) VDD 3.6 V
Reverse Voltage VR -1.5 V
Address-pin Voltage VADDR VDD + 0.6 V
Operating Temperature Range, TA -20 +85 °C
Storage Temperature Range, TS -40 +105 °C
ESD Sensitivity
- HBM (acc. AEC Q100 002) 2 kV
- CDM (acc. AEC Q100 011) 750 V
- Air discharge (acc. IEC61000-4-2) +4 kV
- Contact discharge (acc. IEC61000-4-2) +2 kV
DC current into SCL 10 μA
DC sink current, SDA pin 20 mA
DC clamp current, SDA pin 25 mA
DC clamp current, SCL pin 25 mA
EEPROM re-writes 10
Table 4: Absolute maximum ratings
Exceeding the absolute maximum ratings may cause permanent damage. Exposure to absolute maximum-
rated conditions for extended periods may affect device reliability.
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Datasheet
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Pin definitions and descriptions 5.
Figure 2: MLX90632 TOP view
Pin #
Name
Direction
Description
1 SDA In/Out I
2
C Data line
2 VDD POWER Supply
3 GND GND Ground
4 SCL In I
2
C Clock line
5 ADDR In LSB of I
2
C address
Table 5: Pin definition
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Datasheet
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Electrical characteristics 6.
All parameters are valid for TA = 25 ˚C, VDD = 3.3V (unless otherwise specified)
Parameter Symbol Test Conditions Min Typ Max Units
Supplies
External supply V
DD
3 3.3 3.6 V
Supply current I
DD
No load 0.5 1 1.4 mA
Sleep current IDDpr No load, erase/write EEPROM
operations 1.5 2.5 uA
Power On Reset
POR level V
POR_up
Power-up (full temp range) 1.3 2.4 V
POR level V
POR_down
Power-down (full temp range) 1.1 2.1 V
POR hysteresis V
POR_hys
Full temp range 200 500 mV
VDD rise time (10% to 90% of
specified supply voltage) TPOR Ensure POR signal 20 ms
Output valid
(result in RAM) Tvalid After POR 64 ms
I
2
C compatible 2-wire interface
I2C Voltage VI2C I
2
C version = 1.8V
I2C version = 3.3V
1.65
3
1.8
V
DD
1.95
3.6
V
V
Input high voltage V
IH
Over temperature and supply 0.7*V
I2C
V
I2C
+0.5 V
Input low voltage V
IL
Over temperature and supply -0.5 0.3*V
I2C
V
Output low voltage V
OL
Over temperature and supply 0 0.4 V
Address pin voltage (“1”) V
ADDR,HI
2 V
DD
V
DD
+0.5 V
Address pin voltage (“0”) V
ADDR,LO
0
0.5 V
ADDR leakage I
ADDR, leak
1 μA
SCL leakage I
SCL, leak
V
SCL
=3.6V, Ta=+85°C 1 μA
SDA leakage I
SDA, leak
V
SDA
=3.6V, Ta=+85°C 1 μA
SCL capacitance C
SCL
10 pF
SDA capacitance C
SDA
10 pF
Slave address SA Factory default, ADDR-pin grounded 3A hex
Table 6: Electrical characteristics
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Datasheet
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Detailed General Description 7.
Block diagram 7.1.
Figure 3: Block diagram
Description 7.2.
The MLX90632 is a far infrared, non-contact temperature sensor which is factory calibrated to a high
accuracy. Internally, electrical and thermal precautions are taken to compensate for thermally harsh
external conditions. The thermopile sensing element voltage signal is amplified and digitized. After digital
filtering, the raw measurement result is stored in the RAM memory. Furthermore, the MLX90632 contains a
sensor element to measure the temperature of the sensor itself. The raw information of this sensor is also
stored in RAM after processing. All above functions are controlled by a state machine. The result of each
measurement conversion is accessible via I2C.
The communication to the chip is done by I2C in fast mode plus (FM+). The requirement of the standard is to
run at frequencies up to 1MHz. Through I2C the external unit can have access to the following blocks:
Control registers of internal state machines
RAM (96cells x 16bit) for pixel and auxiliary measurement data, in this document mainly referred to
as ‘storage memory’.
EEPROM (256cells x 16bit) used to store the trimming values, calibration constants and various
device/measurement settings.
From the measurement data and the calibration data the external unit can calculate both the sensor
temperature and the object temperature. The calculation allows the customer to adjust the calibration for
his own application in case an optical window or obstructions are present.
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Datasheet
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Memory map 8.
Access Address Name Description
EEPROM
Read-only 0x2405 ID0[15:0] Chip version
Read-only 0x2406 ID1[15:0] Chip version
Read-only 0x2407 ID2[15:0] Chip version
Read-only 0x2408 ID_CRC16 CRC
Read-only 0x2409 EE_PRODUCT_CODE Sensor information
- - Melexis reserved
Read-only 0x240B EE_VERSION EEPROM version
Read-only 0x240C EE_P_R [15:0] P_R calibration constant (16-bit, Least Significant Word)
Read-only 0x240D EE_P_R [31:16] P_R calibration constant (16-bit, Most Significant Word)
Read-only 0x240E EE_P_G [15:0] P_G calibration constant (16-bit, Least Significant Word)
Read-only 0x240F EE_P_G [31:16] P_G calibration constant (16-bit, Most Significant Word)
Read-only 0x2410 EE_P_T [15:0] P_T calibration constant (16-bit, Least Significant Word)
Read-only 0x2411 EE_P_T [31:16] P_T calibration constant (16-bit, Most Significant Word)
Read-only 0x2412 EE_P_O [15:0] P_O calibration constant (16-bit, Least Significant Word)
Read-only 0x2413 EE_P_O [31:16] P_O calibration constant (16-bit, Most Significant Word)
Read-only 0x2414 EE_Aa [15:0] Aa calibration constant (16-bit, Least Significant Word)
Read-only 0x2415 EE_Aa [31:16] Aa calibration constant (16-bit, Most Significant Word)
Read-only 0x2416 EE_Ab [15:0] Ab calibration constant (16-bit, Least Significant Word)
Read-only 0x2417 EE_Ab [31:16] Ab calibration constant (16-bit, Most Significant Word)
Read-only 0x2418 EE_Ba [15:0] Ba calibration constant (16-bit, Least Significant Word)
Read-only 0x2419 EE_Ba [31:16] Ba calibration constant (16-bit, Most Significant Word)
Read-only 0x241A EE_Bb [15:0] Bb calibration constant (16-bit, Least Significant Word)
Read-only 0x241B EE_Bb [31:16] Bb calibration constant (16-bit, Most Significant Word)
Read-only 0x241C EE_Ca [15:0] Ca calibration constant (16-bit, Least Significant Word)
Read-only 0x241D EE_Ca [31:16] Ca calibration constant (16-bit, Most Significant Word)
Read-only 0x241E EE_Cb [15:0] Cb calibration constant (16-bit, Least Significant Word)
Read-only 0x241F EE_Cb [31:16] Cb calibration constant (16-bit, Most Significant Word)
Read-only 0x2420 EE_Da [15:0] Da calibration constant (16-bit, Least Significant Word)
Read-only 0x2421 EE_Da [31:16] Da calibration constant (16-bit, Most Significant Word)
Read-only 0x2422 EE_Db [15:0] Db calibration constant (16-bit, Least Significant Word)
Read-only 0x2423 EE_Db [31:16] Db calibration constant (16-bit, Most Significant Word)
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REVISION 9 – MAY, 2020
Read-only 0x2424 EE_Ea [15:0] Ea calibration constant (16-bit, Least Significant Word)
Read-only 0x2425 EE_Ea [31:16] Ea calibration constant (16-bit, Most Significant Word)
Read-only 0x2426 EE_Eb [15:0] Eb calibration constant (16-bit, Least Significant Word)
Read-only 0x2427 EE_Eb [31:16] Eb calibration constant (16-bit, Most Significant Word)
Read-only 0x2428 EE_Fa [15:0] Fa calibration constant (16-bit, Least Significant Word)
Read-only 0x2429 EE_Fa [31:16] Fa calibration constant (16-bit, Most Significant Word)
Read-only 0x242A EE_Fb [15:0] Fb calibration constant (16-bit, Least Significant Word)
Read-only 0x242B EE_Fb [31:16] Fb calibration constant (16-bit, Most Significant Word)
Read-only 0x242C EE_Ga [15:0] Ga calibration constant (16-bit, Least Significant Word)
Read-only 0x242D EE_Ga [31:16] Ga calibration constant (16-bit, Most Significant Word)
Read-only 0x242E EE_Gb [15:0] Gb calibration constant (16-bit)
Read-only 0x242F EE_Ka [15:0] Ka calibration constant (16-bit)
Read-only 0x2430 EE_Kb [15:0] Kb calibration constant (16-bit)
- - Melexis reserved
R/W 0x2481 EE_Ha [15:0] Ha Customer calibration constant (16 bit)
R/W 0x2482 EE_Hb [15:0] Hb Customer calibration constant (16 bit)
- - Melexis reserved
R/W 0x24D4 EE_CONTROL EEPROM Control register, measurement control
R/W 0x24D5 EE_I2C_ADDRESS I
2
C slave address >> 1
Example: standard address (= 0x003A) >> 1 = 0x001D
- - Melexis reserved
R/W 0x24E1 EE_MEAS_1 Measurement settings 1 (see section Measurement settings)
R/W 0x24E2 EE_MEAS_2 Measurement settings 2 (see section Measurement settings)
- - Melexis reserved
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REGISTER
R/W 0x3000 REG_I2C_ADDRESS I
2
C slave address >> 1
R/W 0x3001 REG_CONTROL Control register, measurement mode
- - Melexis reserved
R/W 0x3FFF REG_STATUS Status register: data available
RAM
Read-only 0x4000 RAM_1 Raw data 1
Read-only 0x4001 RAM_2 Raw data 2
Read-only 0x4002 RAM_3 Raw data 3
Read-only 0x4003 RAM_4 Raw data 4
Read-only 0x4004 RAM_5 Raw data 5
Read-only 0x4005 RAM_6 Raw data 6
Read-only 0x4006 RAM_7 Raw data 7
Read-only 0x4007 RAM_8 Raw data 8
Read-only 0x4008 RAM_9 Raw data 9
… … … …
Read-only 0x4033 RAM_52 Raw data 52
Read-only 0x4034 RAM_53 Raw data 53
Read-only 0x4035 RAM_54 Raw data 54
Read-only 0x4036 RAM_55 Raw data 55
Read-only 0x4037 RAM_56 Raw data 56
Read-only 0x4038 RAM_57 Raw data 57
Read-only 0x4039 RAM_58 Raw data 58
Read-only 0x403A RAM_59 Raw data 59
Read-only 0x403B RAM_60 Raw data 60
Table 7: Memory table
Important! The width of the EEPROM is 16 bit.
Some calibration parameters are 32 bit and split up into two 16 bit numbers in EEPROM.
The least significant 16 bits of the parameter starts on the address shown in the Memory table.
Example: To retrieve value EE_Aa (32bit) = EE_Aa_MS (at 0x2415) << 16 | EE_Aa_LS (at 0x2414)
(Section Example Temperature Calculation)
Important! The EEPROM needs to be unlocked before each write command.
(Section EEPROM unlock for customer access)
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Datasheet
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REVISION 9 – MAY, 2020
Product ID 8.1.
A unique 48-bit product ID is stored in the EEPROM.
Addresses 0x2405 (ID0), 0x2406 (ID1) and 0x2407 (ID2) should be readout to know the ID of the product.
ProductID[47:0] = ID2[15:0] << 32 | ID1[15:0] << 16 | ID0[15:0]
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
ProductID[15:0]
Figure 4: ID0
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
ProductID[31:16]
Figure 5: ID1
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
ProductID[47:32]
Figure 6: ID2
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Datasheet
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Product Code (0x2409) 8.2.
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
FOV
Package
Accuracy range
Figure 7 EE_PRODUCT_CODE
FOV
0: -
1: 70°
Package
0: -
1: SFN 3x3
Accuracy range
0: -
1: Medical
2: Standard
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Datasheet
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Control and configuration 9.
Several bits in the EEPROM or register are available to control and configure the measurements:
Measurement control 9.1.
Figure 8: Register Measurement control settings
REG_CONTROL controls the measurement handling and data storage.
Changes will take immediate effect.
Bits
Parameter
Description
See section
8:4 meas_select select the type of measurement to be performed Operating Modes
3 soc starts a measurement when being in (sleeping) step mode Operating Modes
2:1 mode[1:0] defines the operating mode (step mode or continuous mode) Operating Modes
Table 8: Register REG_CONTROL explained
Note that this register is initialized during POR by the EEPROM word EE_CONTROL.
Several measurement modes exist. These modes are controlled by bits mode[1:0] in register REG_CONTROL. In
continuous mode the measurements are constantly running while in step mode the state machine will execute
only one measurement which is initiated by soc bit. After finishing the measurement it will go in wait state until
the next measurement is initiated by soc. The measurements are following the measurement sequence as
defined in the measurement table.
The different possible measurement modes are:
mode[1:0] = 01: Enables the sleeping step mode. In this mode the device will be in sleep. On request
(soc bit), the device will power-on, the state machine will do one measurement, will go into sleep
and will wait for next command.
mode[1:0] = 10: Enables the step mode. In this mode the state machine will do one measurement
upon request (soc bit) and will wait for next command. The device remains powered all time in this
mode.
mode[1:0] = 11: Device is in continuous mode. Measurements are executed continuously. The device
remains powered all time in this mode.
By default, the device is in continuous mode.
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Melexis reserved
mode
meas_select
soc
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
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Switching between the step modes and continuous mode has only effect after the current measurement has
finished (not waiting till end of measurement table was reached).
There are only two possible measurements to select from:
meas_select[4:0] = 0x00: Enables the medical measurement. In order to calculate the correct
temperatures, the appropriate raw data values and formulas should be used. Refer to the medical
measurement temperature calculations
meas_select[4:0] = 0x11: Enables the extended range measurement. In order to calculate the correct
temperatures, the appropriate raw data values and formulas should be used. Refer to the extended
range measurement temperature calculations
Note: If other values are being used for meas_select, the resulting calculated temperatures will be
invalid.
In order to switch to the desired measurement type the following routine should be performed:
1. Send an addressed reset to the MLX90632 device
2. Read the register (REG_CONTROL) value
3. Modify the REG_CONTROL value to:
a. mode[1:0] = 00
b. meas_select = 0x00 for medical or 0x11 for extended range
4. Read the register (REG_CONTROL) value
5. Modify the REG_CONTROL value mode[1:0] to the desired mode
The next measurement will be of the type that was programmed
By default, the medical measurement is enabled
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Datasheet
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Device status 9.2.
Figure 9: Register Device status settings
REG_STATUS allows checking in which state the device is and indicates when measurements are finished.
Changes will take immediate effect.
Bits
Parameter
Description
See section
10 device_busy
Read-only
Flag indicating that a measurement is being executed (1 = measurement ongoing)
In sleep mode, this flag is always low.
In continuous mode, this flag is always high.
In soc-step mode, this flag is high during one measurement.
In sob-step mode, this flag is high till all measurements are finished.
9 eeprom_busy
Read-only
Flag indicating that the eeprom is busy (0: not busy)
Eeprom being busy is defined as follows:
- at start-up, the eeprom is busy and remains busy till initialization phase (eeprom
copy) has finished
- during eeprom write/erase, the eeprom is busy
8 brown_out
Bit is set to 0
Customer should set bit to 1
When device is reset, the bit is set to 0 and reset can be detected
6:2 cycle_position
Read-only
Indicates from which measurement (in the measurement table) the last written data
is coming:
- cycle_position[4:0]=x, corresponds to measurement x, x=0->31
Temperature
calculation
0 new_data
Customer should set bit to 0
When a measurement is done, the bit is set to 1
Customer can readout the data and reset the bit to 0
Operating
Modes
Table 9: Register REG_STATUS explained
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Measurement settings 9.3.
9.3.1. Refresh rate
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Melexis reserved
Refresh rate
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Melexis reserved
Figure 10: EEPROM Measurement settings
The refresh rate is the speed that the RAM will be updated with results and is configurable in “Measurement settings 1” and
“Measurement settings 2”.
The refresh rate can be set with 3 bits and is located in EEPROM addresses 0x24E1 and 0x24E2.
Changing the refresh rate will take immediate effect.
It is important to know that the refresh rate should be kept the same for both measurements.
The table below shows the available refresh rates and the corresponding result to be written in EEPROM addresses
EE_MEAS_1 and EE_MEAS_2.
EE_MEAS_1[10:8]
EE_MEAS_2[10:8]
Refresh rate
[Hz] Time [ms] EE_MEAS_1 (0x24E1) EE_MEAS_2 (0x24E2)
0 0.5 2000 0x800D 0x801D
1 1 1000 0x810D 0x811D
2 2 500 0x820D 0x821D
3 4 250 0x830D 0x831D
4 8 125 0x840D 0x841D
5 16 62.5 0x850D 0x851D
6 32 31.25 0x860D 0x861D
7 64 15.625 0x870D 0x871D
Table 10: EEPROM Refresh rate explained
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Datasheet
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REVISION 9 – MAY, 2020
I2C commands 10.
This device is based on I2C specification Rev.5 – October 9th 2012. I2C FM+ mode is supported.
The sensor uses the following I2C features:
Slave mode only
7-bits addressing
Modes: Standard-mode, Fast-mode, Fast-mode Plus
Incremental addressing – allowing a block of addresses to be accessed inside one I2C sequence
The following I2C commands are implemented:
Read/write access to internal memories and registers
Addressed write
Addressed read
Global reset
Addressed reset
EEPROM unlock for CUST access
Direct read
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REVISION 9 – MAY, 2020
I2C address 10.1.
By default, the device responds to the 7-bit slave address 0x3A.
Configuration of the 7-bit slave address is possible at EEPROM address 0x24D5.
The least significant bit (bit0) of the address is determined by the status of the ADDR-pin (either connected to
ground or supply) and is taken in after power-up or reset command if the change is made in EEPROM.
- Bit0 = ‘0’ if ADDR-pin is connected to GND
- Bit0 = ‘1’ if ADDR-pin is connected to VDD
The remaining 6-bits can be used to configure the I2C address of the device.
Figure 11: EEPROM I2C address configuration
Important! The device will not respond if the I2C address is changed to 0 (and ADDR pin is low).
The only way to get the device to respond is to pull the ADDR pin high.
The slave address will be changed to 1 and communication is possible.
Important! The device shall not execute measurements when performing EEPROM memory operations (I2C
read/write instructions in EEPROM address range)! Hence, the device shall be put in halt mode or
in a stepping mode before doing EEPROM read/write operations.
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Page 22 of 53
REVISION 9 – MAY, 2020
Addressed read 10.2.
The addressed read command allows doing an incremental read-out, starting from any given address within the
memory space.
S 0 1 1 1 0 1 0 W
_
A A A
MSByte address LSByte address
SCL
SDA
Slave address
S 0 1 1 1 0 1 0 R A N
A
K
P
MSByte data LSByte data
A
Slave address
Figure 12: Addressed read
Important! An addressed read is only valid when combining directly an addressed write and a direct read
through a repeated START condition. In case the read and write part are separated by a STOP
condition, or in case the read is not directly following the write, or in case the slave address is not
identical for both, the command will not be seen as an addressed read. As a result, the second
read will in practice act as a direct read.
As soon as incremental addressing leaves the address space, the slave will respond with all 8’hFF.
Addressed write 10.3.
The addressed write command allows doing an incremental write, starting from any given address within the
memory space.
S0111010W
_
A A A A A P
MSByte address LSByte address MSByte data LSByte data
SCL
SDA
Slave address
Figure 13: Addressed write
Important! The slave is sending ACK/NACK based on the fact whether it was able to write data (timing, end of
register space, access rights).
The slave will automatically increment the address of the write byte, independent if it gave an
ACK or a NACK to the master. It is up to the master to re-write the byte afterwards.
Before writing to EEPROM it is necessary to erase the specific address location in EEPROM. This is
done by first writing 0x0000. Then the new data can be written.
When the device is busy with the write operation to EEPROM, new write commands will be
ignored. A read operation will return invalid data. The fact that the device is busy is indicated via
the bit device_busy in REG_STATUS.
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REVISION 9 – MAY, 2020
Global reset 10.4.
This command resets all devices on the I2C bus (based on the general call address 0x00).
S 0 0 0 0 0 0 0 W
_
A A P
8'h06
SCL
SDA
Address all devices
Figure 14: Global reset
Addressed reset 10.5.
This command resets the addressed device only (based on the I2C address).
S0111010W
_
A A A A A P
8'h30 8'h05 8'h00 8'h06
SCL
SDA
Slave address
Figure 15: Addressed reset
EEPROM unlock for customer access 10.6.
This command unlocks the EEPROM allowing only one write operation to an EEPROM word in the customer part
of the EEPROM.
After the EEPROM write, the EEPROM access goes back to the “NoKey” access mode.
S0111010W
_
A A A A A P
8'h30 8'h05 8'h55 8'h4C
SCL
SDA
Slave address
Figure 16: EEPROM unlock
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Datasheet
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REVISION 9 – MAY, 2020
Direct read 10.7.
The direct read command allows an incremental read out at a default start address.
This default start address is fixed to the register location REG_STATUS (0x3FFF).
According to the I2C specification, the master will keep sending an acknowledge (A) until it want to stop. This is
indicated by sending a NAK. As a result, the slave will stop driving the SDA-bus as soon as a NAK is received by the
master.
As soon as the incremental addressing leaves the address space, the slave will respond with all 8’hFF.
S01 11010R
MSByte of DEF. ADDR
A
Slave address
SCL
A A A A
LSByte of DEF. ADDR MSByte of DEF. ADDR + 1 LSByte of DEF. ADDR + 1
A A
... MSByte of DEF. ADDR + x MSByte of DEF. ADDR + x
N
A
K
P
SDA
Figure 17: Direct read
MLX90632 FIR sensor
Datasheet
Page 25 of 53
REVISION 9 – MAY, 2020
Operating Modes 11.
The device has 2 states of operation: sleep state and active state.
Sleep state
In this state, most of the circuitry is disabled to limit the current consumption to a few uA.
Active state
In this state, the sensor is active.
Several measurement modes exist. These modes are controlled by bits mode[1:0] in register REG_CONTROL[2:1].
In continuous mode the measurements are constantly running while in step mode the state machine will execute
only one measurement which is initiated by soc bit. After finishing the measurement it will go in wait state until
the next measurement is initiated by soc. The measurements are following the measurement sequence as
defined in the measurement table.
The different possible measurement modes are:
mode[1:0] = 01: Enables the sleeping step mode.
The device will be in sleep mode. On request (soc bit), the device will power-on, the state
machine will do one measurement, will go into sleep and will wait for next command.
mode[1:0] = 10: Enables the step mode.
The state machine will do one measurement upon request (soc bit) and will wait for next
command. The device remains powered all time in this mode.
mode[1:0] = 11: Device is in continuous mode.
Measurements are executed continuously. The device remains powered all time in this mode.
By default, the device is in continuous mode.
Switching between the step modes and continuous mode has only effect after the current measurement has
finished (not waiting till end of measurement table was reached).
There are two possible measurement types to select from:
meas_select[4:0] = 0x00: Enables the medical measurement. In order to calculate the correct
temperatures, the appropriate raw data values and formulas should be used. Refer to the medical
measurement temperature calculations
meas_select[4:0] = 0x11: Enables the extended range measurement. In order to calculate the correct
temperatures, the appropriate raw data values and formulas should be used. Refer to the extended
range measurement temperature calculations
Note: If other values are being used for meas_select, the resulting calculated temperatures will be
invalid.
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Page 26 of 53
REVISION 9 – MAY, 2020
Temperature calculation 12.
Medical measurement 12.1.
To calculate the ambient and object temperature, a set of 2 measurements is required:
Measurement 1: RAM_4, RAM_5, RAM_6;
Measurement 2: RAM_7, RAM_8, RAM_9;
One should notice this requires double the measurement time than specified (= 2 * 500ms).
However, this is only valid for the very first calculation.
After the first calculation, TA and TO should be calculated with the next measurement.
Example:
t0: Measurement 1 => no calculation of TA or TO possible
(cycle_pos = 1) because not all parameters are known
t1: Measurement 2 => calculate TA (RAM_6, RAM_9)
(cycle_pos = 2) calculate TO (RAM_7, RAM_8, RAM_6, RAM_9) => 1s.
t2: Measurement 3 (= 1) => calculate TA (RAM_6, RAM_9)
(cycle_pos = 1) calculate TO (RAM_4, RAM_5, RAM_6, RAM_9) => 0.5s.
t3: Measurement 4 (= 2) => calculate TA (RAM_6, RAM_9)
(cycle_pos = 2) calculate TO (RAM_7, RAM_8, RAM_6, RAM_9) => 0.5s.
t4: …
To calculate the new ambient and object temperature RAM_6 and RAM_9 have to be used.
The choice between [RAM_4 and RAM_5] or [RAM_7 and RAM_8] depends on the current measurement.
REG_STATUS[6:2] (= “cycle_pos”) returns the current position of the measurement defined in the measurement
table.
Using the current and the data from measurement (x-1), TA and TO can be calculated every 500ms.
The complete measurement sequence can be automated by using the new_data bit in combination with
cycle_pos bits.
The sequence should look like the following:
Write new_data = 0
Check when new_data = 1
Read cycle_pos to get measurement pointer
If cycle_pos = 1
Calculate TA and TO base on RAM_4, RAM_5, RAM_6, RAM_9
If cycle_pos = 2
Calculate TA and TO base on RAM_7, RAM_8, RAM_6, RAM_9
Return to top
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Datasheet
Page 27 of 53
REVISION 9 – MAY, 2020
12.1.1. Pre-calculations
12.1.1.1. Ambient
VR =RAM_9+Gb∗RAM_6
12
Gb=EE_Gb∗2
AMB=RAM_6
12 VR
∗2
The parameter EE_Gb is a signed 16-bit number.
12.1.1.2. Object
S=RAM_4+RAM_5
2
OR
S=RAM_7+RAM_8
2
VR =RAM_9+Ka∗RAM_6
12
Ka=EE_Ka∗2
S =S
12 VR
∗2
The parameter EE_Ka is a signed 16-bit number.
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Datasheet
Page 28 of 53
REVISION 9 – MAY, 2020
12.1.2. Ambient temperature
(°)=P_O +−P_R
P_G +P_T ∗(−P_R)
With:
Ta in degrees Celsius
P_R = EE_P_R * 2-8
P_O = EE_P_O * 2-8
P_G = EE_P_G * 2-20
P_T = EE_P_T * 2-44
The parameters EE_P_R, EE_P_O, EE_P_G and EE_P_T are signed 32-bit numbers.
12.1.3. Object temperature
(°)
=
∗∗∗+∗(−)+∗(−)+[]
−.−
With:
Fa = EE_Fa * 2-46
Fb = EE_Fb * 2-36
Ga = EE_Ga * 2-36
Ha = EE_Ha * 2-14
Hb = EE_Hb * 2-10
TO0 = 25°C
TA0 = 25°C
TA =(AMB−Eb)
Ea +25
Ea = EE_Ea * 2-16
Eb = EE_Eb * 2-8
Ta[K] = TADUT + 273.15 in Kelvin
TODUT = Object temperature in 25°C
= 1 = Object Emissivity parameter (not stored in EEPROM, but part of the ‘app’)
The parameters EE_Ea, EE_Eb, EE_Fa, EE_Fb, EE_Ga are signed 32-bit numbers.
The parameters EE_Gb, EE_Ka, EE_Ha and EE_Hb are signed 16-bit numbers.
Note:
One can see that to compute “To (object temperature)”, “To” already needs to be known.
“To (object temperature)” is computed in an iterative manner. In the first iteration “To” is assumed to be 25°C.
In the 2nd iteration the result of first iteration is used, and in the 3rd iteration the end result is obtained.
(See example on next page).
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Datasheet
Page 29 of 53
REVISION 9 – MAY, 2020
12.1.4. Example Medical measurement Temperature Calculation
Assumed are the following calibration parameters read from EEPROM:
ADDR PARAM
DATA
(hex) hex to dec Conversion to use in formula
0x240C EE_P_R [15:0] 0103
EE_P_R = 005D0103hex = 6095107dec P_R = 6095107 * 2-8 = 23809.01
0x240D EE_P_R [31:16] 005D
0x240E EE_P_G [15:0] FAE5
EE_P_G = 051CFAE5hex = 85785317dec P_G = 85785317 * 2-20 = 81.81125
0x240F EE_P_G [31:16] 051C
0x2410 EE_P_T [15:0] 0000
EE_P_T = 00000000hex = 0dec P_T = 0 * 2-44 = 0
0x2411 EE_P_T [31:16] 0000
0x2412 EE_P_O [15:0] 1900
EE_P_O = 00001900hex = 6400dec P_O = 6400 * 2-8 = 25
0x2413 EE_P_O [31:16] 0000
0x2424 EE_Ea [15:0] CFAE
EE_Ea = 0051CFAEhex = 5361582dec Ea = 5361582 * 2-16 = 81.81125
0x2425 EE_Ea [31:16] 0051
0x2426 EE_Eb [15:0] 0103
EE_Eb = 005D0103hex = 6095107dec Eb = 6095107 * 2-8 = 23809.01
0x2427 EE_Eb [31:16] 005D
0x2428 EE_Fa [15:0] 6351
EE_Fa = 03506351hex = 5559995dec Fa = 55599953 * 2-46 = 7.9E-07
0x2429 EE_Fa [31:16] 0350
0x242A EE_Fb [15:0] 71F1
EE_Fb = FE2571F1hex = -31100431dec Fb = -31100431 * 2-36 = -0.00045
0x242B EE_Fb [31:16] FE25
0x242C EE_Ga [15:0] A7A4
EE_Ga = FDFFA7A5hex = -33577052dec Ga = -33577052 * 2-36 = -0.00049
0x242D EE_Ga [31:16] FDFF
0x242E EE_Gb [15:0] 2600 EE_Gb = 2600
hex
= 9728
dec
Gb = 9728 * 2
-10
= 9.5
0x242F EE_Ka [15:0] 2A00 EE_Ka = 2A00
hex
= 10752
dec
Ka = 10752 * 2
-10
= 10.5
0x2481 EE_Ha [15:0] 4000 EE_Ha = 4000hex = 16384dec Ha = 16384 * 2
-14
= 1
0x2482 EE_Hb [15:0] 0000 EE_Hb = 0000
hex
= 0
dec
Hb = 0 * 2
-10
= 0
Table 11: Example EEPROM calibration parameters
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Datasheet
Page 30 of 53
REVISION 9 – MAY, 2020
The returned values from the RAM (0x4000 to 0x4008):
ADDR PARAM
DATA
(hex)
DATA
(dec)
0x4003 RAM_4 FF9B -101
0x4004 RAM_5 FF9D -99
0x4005 RAM_6 57E4 22500
0x4006 RAM_7 FF97 -105
0x4007 RAM_8 FF99 -103
0x4008 RAM_9 59D8 23000
Table 12: Example RAM data
12.1.4.1. Ambient temperature calculation
VR =RAM_9+Gb∗RAM_6
12 =23000+9.5∗22500
12
VR =40812.5
AMB=RAM_6
12 VR
∗2=22500
12 40812.5 ∗2
AMB=24086.73813
(sensortemperaturein°C)=P_O+AMB−P_R
P_G +P_T∗(AMB−P_R)
=25+24086.73813−23809.01
81.81125 +0∗(24086.73813−23809.01)
Ta=28.395°C
=28.4°
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Datasheet
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REVISION 9 – MAY, 2020
12.1.4.2. Object temperature calculation
S=RAM_4+RAM_5
2=(−101)+(−99)
2
S=−100
OR
S=RAM_7+RAM_8
2=(−105)+(−103)
2
S=−104
Assumed is that RAM_4 and RAM_5 are updated lastly by the device (cycle_pos = 1)
VR =RAM_9+Ka∗RAM_6
12 =23000+10.5∗22500
12
VR =42687.5
S =S
12VR
∗2=−100
12 42687.5 ∗2
S =−102.35
TO0 = 25°C
TA0 = 25°C
TA=(AMB−Eb)
Ea +25=(24086.73813−23809.01)
81.81125 +25=28.3947
Ta[K] = TADUT + 273.15 = 28.3947 + 273.15 = 301.5447
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REVISION 9 – MAY, 2020
T(objecttemperaturein°C)
=S
ε∗Fa∗Ha∗1+Ga∗(TO−TO)+Fb∗(TA−TA)+Ta[]
−273.15−Hb
The emissivity parameter (Ɛ) is controlled by the user and is assumed in this example equal to 1.
TODUT = 25 for the first calculation
=−102.35
1∗(7.9E−07)∗1∗1+(−0.00049)∗(25−25)+(−0.00045)∗(28.3947−25)+(301.5447)
−273.15−0 To=27.2048027°C
The object temperature needs to be calculated 3 times in order the get the end result.
Next object temperature calculation uses previous obtained object temperature.
=−102.35
1∗(7.9E−07)∗1∗1+(−0.00049)∗(.−25)+(−0.00045)∗(28.3947−25)+(301.5447)
−273.15−0
To=27.2035098°C
=−102.35
1∗(7.9E−07)∗1∗1+(−0.00049)∗(.−25)+(−0.00045)∗(28.3947−25)+(301.5447)
−273.15−0
To=27.20351053°C
=.°C
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Datasheet
Page 33 of 53
REVISION 9 – MAY, 2020
Extended range measurement 12.2.
This measurement type option is implemented in order to give additional range to the medical devices.
When using the extended range measurement the following should be done:
1. Switch the device to extended range measurement mode
2. Wait for the whole measurement to finish
3. Use the following routine to read the data of interest and calculate the temperatures.
All the necessary functions are available at https://github.com/melexis/mlx90632-library
To calculate the ambient and object temperature, a set of 3 measurements is required:
Measurement 1: RAM_52, RAM_53, RAM_54;
Measurement 2: RAM_55, RAM_56, RAM_57;
Measurement 3: RAM_58, RAM_59, RAM_60;
All three measurements should be available for proper temperature calculation.
12.2.1. Pre-calculations
12.2.1.1. Ambient
VR =RAM_57+Gb∗RAM_54
12
Gb=EE_Gb∗2
AMB=RAM_54
12 VR
∗2
The parameter EE_Gb is a signed 16-bit number.
12.2.1.2. Object
S=RAM_52−RAM_53−RAM_55+RAM_56
2+_58+_59
OR
VR =RAM_57+Ka∗RAM_54
12
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Datasheet
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REVISION 9 – MAY, 2020
Ka=EE_Ka∗2
S =S
12 VR
∗2
The parameter EE_Ka is a signed 16-bit number.
12.2.2. Ambient temperature
(°)=P_O +−P_R
P_G +P_T ∗(−P_R)
With:
Ta in degrees Celsius
P_R = EE_P_R * 2-8
P_O = EE_P_O * 2-8
P_G = EE_P_G * 2-20
P_T = EE_P_T * 2-44
The parameters EE_P_R, EE_P_O, EE_P_G and EE_P_T are signed 32-bit numbers.
12.2.3. Object temperature
(°)
=
∗
∗∗+∗(−)+∗(−)+[]
−.−
With:
Fa = EE_Fa * 2-46
Fb = EE_Fb * 2-36
Ga = EE_Ga * 2-36
Ha = EE_Ha * 2-14
Hb = EE_Hb * 2-10
TO0 = 25°C
TA0 = 25°C
TA =(AMB−Eb)
Ea +25
Ea = EE_Ea * 2-16
Eb = EE_Eb * 2-8
Ta[K] = TADUT + 273.15 in Kelvin
TODUT = Object temperature in 25°C
= 1 = Object Emissivity parameter (not stored in EEPROM, but part of the ‘app’)
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REVISION 9 – MAY, 2020
The parameters EE_Ea, EE_Eb, EE_Fa, EE_Fb, EE_Ga are signed 32-bit numbers.
The parameters EE_Gb, EE_Ka, EE_Ha and EE_Hb are signed 16-bit numbers.
Note:
One can see that to compute “To (object temperature)”, “To” already needs to be known.
“To (object temperature)” is computed in an iterative manner. In the first iteration “To” is assumed to be 25°C.
In the 2nd iteration the result of first iteration is used, and in the 3rd iteration the end result is obtained.
(See example on next page).
MLX90632 FIR sensor
Datasheet
Page 36 of 53
REVISION 9 – MAY, 2020
12.2.4. Example Extended range measurement Temperature Calculation
Assumed are the following calibration parameters read from EEPROM:
ADDR PARAM
DATA
(hex) hex to dec Conversion to use in formula
0x240C EE_P_R [15:0] 0103
EE_P_R = 005D0103hex = 6095107dec P_R = 6095107 * 2-8 = 23809.01
0x240D EE_P_R [31:16] 005D
0x240E EE_P_G [15:0] FAE5
EE_P_G = 051CFAE5hex = 85785317dec P_G = 85785317 * 2-20 = 81.81125
0x240F EE_P_G [31:16] 051C
0x2410 EE_P_T [15:0] 0000
EE_P_T = 00000000hex = 0dec P_T = 0 * 2-44 = 0
0x2411 EE_P_T [31:16] 0000
0x2412 EE_P_O [15:0] 1900
EE_P_O = 00001900hex = 6400dec P_O = 6400 * 2-8 = 25
0x2413 EE_P_O [31:16] 0000
0x2424 EE_Ea [15:0] CFAE
EE_Ea = 0051CFAEhex = 5361582dec Ea = 5361582 * 2-16 = 81.81125
0x2425 EE_Ea [31:16] 0051
0x2426 EE_Eb [15:0] 0103
EE_Eb = 005D0103hex = 6095107dec Eb = 6095107 * 2-8 = 23809.01
0x2427 EE_Eb [31:16] 005D
0x2428 EE_Fa [15:0] 6351
EE_Fa = 03506351hex = 5559995dec Fa = 55599953 * 2-46 = 7.9E-07
0x2429 EE_Fa [31:16] 0350
0x242A EE_Fb [15:0] 71F1
EE_Fb = FE2571F1hex = -31100431dec Fb = -31100431 * 2-36 = -0.00045
0x242B EE_Fb [31:16] FE25
0x242C EE_Ga [15:0] A7A4
EE_Ga = FDFFA7A5hex = -33577052dec Ga = -33577052 * 2-36 = -0.00049
0x242D EE_Ga [31:16] FDFF
0x242E EE_Gb [15:0] 2600 EE_Gb = 2600
hex
= 9728
dec
Gb = 9728 * 2
-10
= 9.5
0x242F EE_Ka [15:0] 2A00 EE_Ka = 2A00
hex
= 10752
dec
Ka = 10752 * 2
-10
= 10.5
0x2481 EE_Ha [15:0] 4000 EE_Ha = 4000hex = 16384dec Ha = 16384 * 2
-14
= 1
0x2482 EE_Hb [15:0] 0000 EE_Hb = 0000
hex
= 0
dec
Hb = 0 * 2
-10
= 0
Table 13: Example EEPROM calibration parameters
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Datasheet
Page 37 of 53
REVISION 9 – MAY, 2020
The returned values from the RAM (0x4033 to 0x403A):
ADDR PARAM
DATA
(hex)
DATA
(dec)
0x4033 RAM_52 FE64 -412
0x4034 RAM_53 FEAB -341
0x4035 RAM_54 57E4 22500
0x4036 RAM_55 FEA3 -349
0x4037 RAM_56 FE6A -406
0x4038 RAM_57 59D8 23000
0x4039 RAM_58 000B 11
0x403A RAM_59 0009 9
Table 14: Example RAM data
12.2.4.1. Ambient temperature calculation
VR =RAM_57+Gb∗RAM_54
12 =23000+9.5∗22500
12
VR =40812.5
AMB=RAM_54
12 VR
∗2=22500
12 40812.5 ∗2
AMB=24086.73813
(sensortemperaturein°C)=P_O+AMB−P_R
P_G +P_T∗(AMB−P_R)
=25+24086.73813−23809.01
81.81125 +0∗(24086.73813−23809.01)
Ta=28.395°C
=28.4°
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Datasheet
Page 38 of 53
REVISION 9 – MAY, 2020
12.2.4.2. Object temperature calculation
S=RAM_52−RAM_53−RAM_55+RAM_56
2+_58+_59
S=(−412)−(−341)−(−349)+(−406)
2+11+9
S=−44
VR =RAM_57+Ka∗RAM_54
12 =23000+10.5∗22500
12
VR =42687.5
S =S
12VR
∗2=−44
1242687.5 ∗2
S =−45.034
TO0 = 25°C
TA0 = 25°C
TA=(AMB−Eb)
Ea +25=(24086.73813−23809.01)
81.81125 +25=28.3947
Ta[K] = TADUT + 273.15 = 28.3947 + 273.15 = 301.5447
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Datasheet
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REVISION 9 – MAY, 2020
T(objecttemperaturein°C)
=S
ε∗Fa
2∗Ha∗1+Ga∗(TO−TO)+Fb∗(TA−TA)+Ta[]
−273.15−Hb
The emissivity parameter (Ɛ) is controlled by the user and is assumed in this example equal to 1.
TODUT = 25 for the first calculation
=−45.034
1∗7.9E−07
2∗1∗1+(−0.00049)∗(25−25)+(−0.00045)∗(28.3947−25)+(301.5447)
−273.15−0 To=27.34837117°C
The object temperature needs to be calculated 3 times in order the get the end result.
Next object temperature calculation uses previous obtained object temperature.
=−45.034
1∗7.9E−07
2∗1∗1+(−0.00049)∗(.−25)+(−0.00045)∗(28.3947−25)+(301.5447)
−273.15−0
To=27.34715755°C
=−102.35
1∗7.9E−07
2∗1∗1+(−0.00049)∗(.−25)+(−0.00045)∗(28.3947−25)+(301.5447)
−273.15−0
To=27.34715818°C
=.°C
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Performance characteristics 13.
Accuracy 13.1.
The calculated ambient temperature has an accuracy of ±3˚C between -20˚C and 85˚C of ambient temperature.
Between 15˚C and 45˚C the accuracy is ±1˚C.
All accuracy specifications apply under settled isothermal conditions only.
13.1.1. Standard
Figure 18: Standard accuracy table
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13.1.2. Medical
Figure 19: Medical accuracy table
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Field of View (FoV) 13.2.
Figure 20: Field of View measurement principle
Parameter 50% of maximum 10% of maximum Unit
Field Of View 50 70 ° (angular degrees)
Table 15: Field Of View of the MLX90632
Figure 21: Field of View of MLX90632 (FoV = 50˚)
The 50° is measured at the 50% level of sensitivity.
For high accuracy applications, one should take care that the field of view is not obstructed by the enclosure of
the application. For this, one has to take care that no obstruction is in a cone of at least 70° wide.
Point heat source
Rotated sensor
Angle of incidence
100%
50%
Sensitivity
Field Of View
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Noise 13.3.
Measurement conditions for noise performance are To = Ta = 25°C.
Note:
Due to the nature of thermal infrared radiation, it is normal that the noise will decrease for high temperature and
increase for lower temperatures.
Figure 22: NETD vs. Refresh rate
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Mechanical Drawing 14.
Package dimensions 14.1.
Figure 23: Package dimensions for MLX90632 (FoV = 50°)
Symbol Min Nom Max
DD = EE 3.00 BSC
AT 0.90 0.95 1.00
Ra 0.05
D2 2.40 2.50 2.60
E2 2.00 2.10 2.20
Lo1 0.15 Max
Kk 0.20 0.30 --
NXL 0.35 0.40 0.45
e1 0.50 BSC
NminOne_e (5-1)*e1
Ti 0.18 0.25 0.30
Tolerance (A_CC – A_CP) -0.15 0.15
Tolerance (A_CC – A_CD) -0.1 0.1
Table 16: Package dimensions for MLX90632 (FoV = 50°)
*BSC Ξ basic dimension *A_CC = Center of silicon Cap *A_CD = Center of Die frame *A_CP = Center of Package
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PCB footprint 14.2.
Figure 24: PCB footprint for MLX90632
Symbol Distance [mm]
a 0.60
b 0.25
c 2.10
d 2.50
e 3.00
f 3.00
g 0.60/0.80/1.00
h 0.20
i 0.50
j 0.30
k 10 (max.)
Table 17 : PCB footprint dimensions for MLX90632
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Application schematic 15.
3V3 I2C mode 15.1.
Figure 25: Typical application schematic for 3V3 I2C communication with MLX90632
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1V8 I2C mode 15.2.
Figure 26: Typical application schematic for 1V8 I2C communication with MLX90632
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Software 16.
MLX90632 library on Github:
https://github.com/melexis/mlx90632-library
Example usage of the MLX90632 Library with Keil IDE:
https://github.com/melexis/mlx90632-example
Evaluation board EVB90632:
https://www.melexis.com/en/documents/tools/tools-evb90632-software-exe
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Standard information regarding manufacturability 17.
of Melexis products with different soldering processes
The MLX90632 is a MSL-3 device.
Our products are classified and qualified regarding soldering technology, solderability and moisture sensitivity
level according to following test methods:
Reflow Soldering SMD’s (Surface Mount Devices)
IPC/JEDEC J-STD-020
Moisture/Reflow Sensitivity Classification for Nonhermetic Solid State Surface Mount Devices
(Classification reflow profiles according to table 5-2)
EIA/JEDEC JESD22-A113
Preconditioning of Nonhermetic Surface Mount Devices Prior to Reliability Testing
(Reflow profiles according to table 2)
Wave Soldering SMD’s (Surface Mount Devices) and THD’s (Through Hole Devices)
EN60749-20
Resistance of plastic- encapsulated SMD’s to combined effect of moisture and soldering heat
EIA/JEDEC JESD22-B106 and EN60749-15
Resistance to soldering temperature for through-hole mounted devices
Iron Soldering THD’s (Through Hole Devices)
EN60749-15
Resistance to soldering temperature for through-hole mounted devices
Solderability SMD’s (Surface Mount Devices) and THD’s (Through Hole Devices)
EIA/JEDEC JESD22-B102 and EN60749-21
Solderability
For all soldering technologies deviating from above mentioned standard conditions (regarding peak temperature,
temperature gradient, temperature profile etc.) additional classification and qualification tests have to be agreed
upon with Melexis.
The application of Wave Soldering for SMD’s is allowed only after consulting Melexis regarding assurance of
adhesive strength between device and board.
Melexis recommends reviewing on our web site the General Guidelines soldering recommendation
(http://www.melexis.com/Quality_soldering.aspx).
Melexis is contributing to global environmental conservation by promoting lead free solutions. For more
information on qualifications of RoHS compliant products (RoHS = European directive on the Restriction Of the
use of certain Hazardous Substances) please visit the quality page on our website:
http://www.melexis.com/quality.aspx
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ESD Precautions 18.
Electronic semiconductor products are sensitive to Electro Static Discharge (ESD).
Always observe Electro Static Discharge control procedures whenever handling semiconductor products.
Application comments 19.
1. Significant contamination at the optical input side (sensor filter) might cause unknown additional
filtering/distortion of the optical signal and therefore result in unspecified errors.
2. IR sensors are inherently susceptible to errors caused by thermal gradients. There are physical reasons for
these phenomena and, in spite of the careful design of the MLX90632, it is recommended not to subject the
MLX90632 to heat transfer and especially transient conditions.
3. The MLX90632 is designed and calibrated to operate as a non-contact thermometer in settled conditions.
4. Upon power-up the MLX90632 passes embedded checking and calibration routines. During these routines the
output is not defined and it is recommended to wait for the specified POR time before reading the module.
Very slow power-up may cause the embedded POR circuitry to trigger on inappropriate levels, resulting in
unspecified operation and this is not recommended.
5. Capacitive loading on an I2C bus can degrade the communication. Some improvement is possible with use of
current sources compared to resistors in pull-up circuitry. Further improvement is possible with specialized
commercially available bus accelerators.
6. A sleep mode is available in the MLX90632. This mode is entered and exited via the I2C compatible 2-wire
communication.
7. A power supply and decoupling capacitor is needed as with most integrated circuits. The MLX90632 is a mixed-
signal device with sensors, small signal analog part, digital part and I/O circuitry. In order to keep the noise
low, power supply switching noise needs to be decoupled. High noise from external circuitry can also affect
noise performance of the device. In many applications a 10nF SMD ceramic capacitor close to the Vdd and Vss
pins would be a good choice. It should be noted that not only the trace to the Vdd pin needs to be short, but
also the one to the Vss pin.
8. Do not perform measurements in oily or helium environments
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Table of figures 20.
Figure 1: Image of MLX90632 .......................................................................................................................................................... 1
Figure 2: MLX90632 TOP view ......................................................................................................................................................... 8
Figure 3: Block diagram .................................................................................................................................................................10
Figure 4: ID0 ..................................................................................................................................................................................14
Figure 5: ID1 ..................................................................................................................................................................................14
Figure 6: ID2 ..................................................................................................................................................................................14
Figure 7 EE_PRODUCT_CODE .........................................................................................................................................................15
Figure 8: Register Measurement control settings ...........................................................................................................................16
Figure 9: Register Device status settings ........................................................................................................................................18
Figure 10: EEPROM Measurement settings .....................................................................................................................................19
Figure 11: EEPROM I2C address configuration ................................................................................................................................21
Figure 12: Addressed read .............................................................................................................................................................22
Figure 13: Addressed write ............................................................................................................................................................22
Figure 14: Global reset ...................................................................................................................................................................23
Figure 15: Addressed reset ............................................................................................................................................................23
Figure 16: EEPROM unlock .............................................................................................................................................................23
Figure 17: Direct read ....................................................................................................................................................................24
Figure 18: Standard accuracy table ................................................................................................................................................40
Figure 19: Medical accuracy table ..................................................................................................................................................41
Figure 20: Field of View measurement principle .............................................................................................................................42
Figure 21: Field of View of MLX90632 (FoV = 50˚) ...........................................................................................................................42
Figure 22: NETD vs. Refresh rate ....................................................................................................................................................43
Figure 23: Package dimensions for MLX90632 (FoV = 50°) ..............................................................................................................44
Figure 24: PCB footprint for MLX90632 ..........................................................................................................................................45
Figure 25: Typical application schematic for 3V3 I2C communication with MLX90632 ......................................................................46
Figure 26: Typical application schematic for 1V8 I2C communication with MLX90632 ......................................................................47
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Disclaimer 21.
Devices sold by Melexis are covered by the warranty and patent indemnification provisions appearing in its Term of
Sale. Melexis makes no warranty, express, statutory, implied, or by description regarding the information set forth
herein or regarding the freedom of the described devices from patent infringement. Melexis reserves the right to
change specifications and prices at any time and without notice. Therefore, prior to designing this product into a
system, it is necessary to check with Melexis for current information. This product is intended for use in normal
commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or
high reliability applications, such as military, medical life-support or life-sustaining equipment are specifically not
recommended without additional processing by Melexis for each application.
The information furnished by Melexis is believed to be correct and accurate. However, this User Manual is intended as
an aid to enable a user to install engineering parts of the MLX90632 into his own application for evaluation. While
Melexis intends for the final production part of the MLX90632 to be comparable to the engineering parts, it is highly
probable that changes will still be implemented.
Melexis shall not be liable to recipient or any third party for any damages, including but not limited to personal injury,
property damage, loss of profits, loss of use, interrupt of business or indirect, special incidental or consequential
damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical data
herein. No obligation or liability to recipient or any third party shall arise or flow out of Melexis’ rendering of technical
or other services.
© 2019 Melexis N.V. All rights reserved.
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Contact Information 22.
For the latest version of this document, go to our website at
www.melexis.com
Or for additional information contact Melexis Direct:
Europe, Africa, Asia:
America:
Phone: +32 1367 0495 Phone: +1 248 306 5400
E-mail: sales_europe@melexis.com E-mail: sales_usa@melexis.com
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