MLX90621
16x4 IR array
Datasheet
Features and Benefits
Applications Examples
Small size, low cost 16x4 pixels IR array
Easy to integrate
Industry standard four lead TO39 package
Factory calibrated infrared temperature
measurement.
Calibration parameters stored in EEPROM.
Noise Equivalent Temperature Difference (NETD)
0.20K RMS @4Hz refresh rate
2
I C compatible digital interface
Programmable frame rate 0.5Hz…512Hz
2.6V supply voltage
Current consumption less than 9mA
Sleep mode consumption less than 7µA
Measurement start trigger for synchronization
with external control unit
3 FOV - 40°x10°, 60°x16° and 120°x25°
Ta -40°C to 85°C
To -20°C to 300°C
Complies with RoHS regulations
High precision non-contact temperature
measurements;
Temperature sensing element for residential,
commercial and industrial building air
conditioning;
Microwave ovens
Home appliances with temperature control;
Thermal Comfort sensor in automotive Air
Conditioning control system;
Passenger classification
Automotive blind angle detection;
Industrial temperature control of moving parts;
Identifying thermal leaks in homes
Thermal scanners
Security / safety gates
Intrusion / Movement detection;
Presence detection / Person localization
Ordering Information
Part No.
Temperature
Code
E (-40°C to 85°C)
MLX90621
Package
Code
SF (TO-39)
(1) Supply Voltage
B = 2.6V
Option Code
-X X X
(1) (2) (3)
(2) Number of
thermopiles:
A = 16X4
Standard
part
-000
Packing
form
-TU
(3) Package options:
A = 120°x25° FOV
B = 60°x16° FOV
C = reserved
D = 40°x10° FOV
Example:
MLX90621ESF-BAB-000-TU
Functional diagram
Digital Active Thermopile Array
Digital filtering
RAM memory
VDD
EEPROM
I2C interface
CLK
39001090621
Rev 3.0
SDA
VSS
General Description
The MLX90621 is a fully calibrated 16x4 pixels IR array
in an industry standard 4-lead TO-39 package. It
contains 2 chips in one package: the MLX90670 (IR
array with signal conditioning electronics) and the
24AA02 (256x8 EEPROM) chip.
The MLX90621 contains 64 IR pixels with dedicated
low noise chopper stabilized amplifier and fast ADC
integrated. A PTAT (Proportional To Absolute
Temperature) sensor is integrated to measure the
ambient temperature of the chip. The outputs of both
IR and PTAT sensors are stored in internal RAM and
2
are accessible through I C.
Page 1 of 44
Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
General Description (continued)
The results of the infrared sensor measurements are stored in RAM:
• 15...18-bit result of IR measurement for each individual sensor (64 words)
• 15…18-bit result of PTAT sensor
Depending on the application, the external microcontroller can read the different RAM data and, based on the
calibration data stored in the EEPROM memory, compensate for difference between sensors to build up a thermal
image, or calculate the temperature at each spot of the imaged scene.
These constants are accessible by the user microcontroller through the I2C bus and have to be used for external post
processing of the thermal data. This post processing includes:
• Ta calculation
• Pixel offset cancelling
• Pixel to pixel sensitivity difference compensation
• Object emissivity compensation
• Object temperature calculation
The result is an image with NETD better than 0.1K RMS at 1Hz refresh rate.
The refresh rate of the array is programmable by means of register settings or directly via I2C command. Changes of
the refresh rate have a direct impact on the integration time and noise bandwidth (faster refresh rate means higher
noise level). The frame rate is programmable in the range 0.5Hz…512Hz and can be changed to achieve the desired
trade-off between speed and accuracy.
The MLX90621 requires a single 2.6V…3.2V although the device is calibrated and performs best at VDD=2.6V.
The MLX90621 is factory calibrated in following temperature ranges:
• -40˚C…85˚C for the ambient temperature sensor
• -50˚C…300˚C for the object temperature.
NOTE: The sensor can detect higher temperatures, but is not calibrated for temperatures above 300°C.
See Table 21 for configuration specific properties.
Each pixel of the array measures the average temperature of all objects in its own Field Of View (called nFOV).
It is very important for the application designer to understand that the accuracy of the temperature measurement
is very sensitive to the thermal equilibrium isothermal conditions (there are 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.
39001090621
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Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
1. Table of contents
1. Table of contents.......................................................................................................................................................... 3
2. Glossary of terms ......................................................................................................................................................... 5
3. Absolute Maximum ratings .......................................................................................................................................... 5
4. Pin definition and description ...................................................................................................................................... 6
5. Electrical characteristics ............................................................................................................................................... 7
6. Block diagram ............................................................................................................................................................... 8
7. Principle of operation ................................................................................................................................................... 9
7.1. Initialization ......................................................................................................................................................... 10
7.1.1. Reading configuration .................................................................................................................................. 11
7.2. Read measurement data (RAM data) .................................................................................................................. 12
7.2.1. PTAT data read ............................................................................................................................................. 12
7.2.2. IR data read .................................................................................................................................................. 12
7.3. Calculation ........................................................................................................................................................... 14
7.3.1. Calculation of absolute chip temperature Ta (sensor temperature) ........................................................... 14
7.3.2. Example for Ta calculations .......................................................................................................................... 15
7.3.3. Calculation of To........................................................................................................................................... 17
7.3.4. Example for To calculations.......................................................................................................................... 20
8. Detailed description, Block description...................................................................................................................... 23
8.1. Pixel position ....................................................................................................................................................... 23
8.2. MLX90621 address map ...................................................................................................................................... 24
8.2.1. RAM .............................................................................................................................................................. 24
8.2.2. Internal registers .......................................................................................................................................... 25
8.2.2.1 Configuration register (0x92) ..................................................................................................................... 25
8.2.2.2 Trimming register (0x93) ............................................................................................................................ 26
8.2.3. EEPROM........................................................................................................................................................ 26
8.3. POR ...................................................................................................................................................................... 28
8.4. ESD ...................................................................................................................................................................... 28
9. Communication protocol ........................................................................................................................................... 28
9.1. Communication pins ........................................................................................................................................... 28
9.2. Low level communication protocol ..................................................................................................................... 29
9.2.1. Start / Stop condition ................................................................................................................................... 29
9.2.2. Device addressing......................................................................................................................................... 29
9.2.3. Acknowledge ................................................................................................................................................ 29
9.2.4. Low level communication operation ............................................................................................................ 29
9.3. Device modes ...................................................................................................................................................... 30
9.3.1. Normal mode ............................................................................................................................................... 30
9.3.2. Step mode .................................................................................................................................................... 30
9.3.3. Power saving mode ...................................................................................................................................... 30
9.4. Communication to IR array ................................................................................................................................. 31
9.4.1. Start measurement command ..................................................................................................................... 31
9.4.2. Read command ............................................................................................................................................ 31
9.4.3. Write configuration register command ........................................................................................................ 32
9.4.4. Write trimming command ............................................................................................................................ 32
9.5. Communication to EEPROM ................................................................................................................................ 33
10. Performance Graphs ................................................................................................................................................ 34
10.1. Temperature accuracy of the MLX90621 .......................................................................................................... 34
10.2. Noise performance and resolution ................................................................................................................... 35
10.3. Field Of View (FOV) ........................................................................................................................................... 36
11. Applications Information.......................................................................................................................................... 37
2
11.1. Use of the MLX90621 thermometer in I C configuration ................................................................................. 37
39001090621
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Datasheet IR16x4
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MLX90621
16x4 IR array
Datasheet
12. Application Comments ............................................................................................................................................. 37
13. Standard information regarding manufacturability of Melexis products with different soldering processes ......... 39
14. ESD Precautions ....................................................................................................................................................... 39
15. FAQ ........................................................................................................................................................................... 40
16. Mechanical specification .......................................................................................................................................... 42
16.1. Package outline ................................................................................................................................................. 42
16.2. Part marking ...................................................................................................................................................... 43
17. References ................................................................................................................................................................ 44
18. Disclaimer ................................................................................................................................................................. 44
39001090621
Rev 3.0
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Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
2. Glossary of terms
POR
PTAT
IR
IR_data
ADC
Ta
To
TGC
FOV
nFOV
ESD
EMC
2
IC
SDA
SCL
FpS
MD
SD
TBD
NA
Power On Reset
Proportional To Absolute Temperature sensor (package temperature)
Infra Red
Infrared data (raw data from ADC proportional to IR energy received by the sensor)
Analog To Digital Converter
Ambient Temperature measured from the chip – (the package temperature)
Object Temperature, ‘seen’ from IR sensor
Temperature Gradient Coefficient
Field Of View
Field Of View of N-th pixel
Electro-Static Discharge
Electro-Magnetic Compatibility
Inter-Integrated Circuit communication protocol
Serial Data
Serial Clock
Frames per Second – data refresh rate
Master Device
Slave Device
To Be Defined
Not Applicable
Table 1 Glossary of terms
3. Absolute Maximum ratings
Parameter
MLX90621
Supply Voltage, VDD (over voltage)
Supply Voltage, VDD (operating max)
Reverse Voltage (each pin)
Operating Temperature Range, TA
Storage Temperature Range, TS
ESD Sensitivity (AEC Q100 002)
DC sink current, SDA
DC source current, SDA
DC clamp current, SDA
DC source current, SCL
DC clamp current, SCL
5.5V
3.6V
-0.3 V
-40…+85°C
-40…+125°C
4kV
50 mA
NA (open drain)
25 mA
NA (input only)
25 mA
Table 2 Absolute maximum ratings for MLX90621
Exceeding the absolute maximum ratings may cause permanent damage. Exposure to absolute-maximum-rated
conditions for extended periods may affect device reliability.
39001090621
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Datasheet IR16x4
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MLX90621
16x4 IR array
Datasheet
4. Pin definition and description
Figure 1 Pin description
Pin Name
Function
SCL
Serial clock input for 2 wire communications protocol
SDA
Digital input / output 2 wire communications protocol.
VDD
External supply voltage
VSS
Ground (case)
Table 3 Pin description for MLX90621
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Datasheet IR16x4
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MLX90621
16x4 IR array
Datasheet
5. Electrical characteristics
All parameters are valid for TA = 25˚C, VDD =2.6V (unless otherwise specified)
Parameter
Symbol
Test Conditions
Min
Typ
Max
Units
2.5
2.6
3.3
V
5
9
mA
7
µA
Supplies
External supply
1
VDD
Supply current
IDD
No load
Sleep current
Islp
No load
POR level
VPOR_up
Power-up (full temp range)
2
2.2
2.4
V
POR level
VPOR_down
Power –down (full temp range)
1.9
2.1
2.3
V
VPOR_hys
Full temp range
TPOR
Ensure POR signal
Power On Reset
POR hysteresis
VDD rise time (10% to 90% of
specified supply voltage)
0.1
V
100
µs
2
I C compatible 2-wire interface Sensor chip
Slave address
SA
Factory default
Input high voltage
VIH (Ta, V)
Over temperature and supply
60
hex
Input low voltage
VIL (Ta, V)
Over temperature and supply
0.3VDD
V
Output low voltage
VOL
SDA over temperature and supply,
Isink = 6mA (FM mode)
0.6
V
Output low voltage
VOL
SDA over temperature and supply,
Isink = 20mA (FM+ mode)
0.4
V
0.7VDD
V
SCL leakage
ISCL, leak
VSCL=4V, Ta=+85°C
2
µA
SDA leakage
ISDA, leak
VSDA=4V, Ta=+85°C
2
µA
SCL capacitance
CSCL
Two dies MLX90670 + EEPROM
20
pF
I C clock frequency
SCLIR
MLX90621 (FM+ mode)
1
MHz
Acknowledge setup time
Tsuac(MD)
8-th SCL falling edge, Master
0.45
µs
Acknowledge hold time
Thdac(MD)
9-th SCL falling edge, Master
0.45
µs
2
Acknowledge setup time
Tsuac(SD)
8-th SCL falling edge, Slave
0.45
µs
Acknowledge hold time
Thdac(SD)
9-th SCL falling edge, Slave
0.45
µs
Slave address
SA
Factory default
I C clock frequency
SCLEEPROM
EEPROM (FM mode)
EEPROM
2
50
hex
400
kHz
Data retention
Ta = +85°C
200
years
Erase/write cycles
Ta = +25°C
1M
Times
Ta = +125°C
100K
Erase/write cycles
Times
Erase cell time
T_erase
5
ms
Write cell time
T_write
5
ms
Table 4 Electrical specification parameters of MLX90621
1) The device can be supplied with VDD = 2.6…3.3V but the best performance is achieved at VDD=2.6V. For supply
voltages above 2.7V a compensation algorithm should be applied for compensating the temperature readings.
39001090621
Rev 3.0
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Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
6. Block diagram
Digital Active Thermopile Array
Digital filtering
RAM
memory
EEPROM
Voltage
regulator
I2C interface
SDA
CLK
VSS
VDD
Figure 2 Block diagram
The device consists of 2 chips packed in single TO-39 package
•
•
IR array and processing electronics
EEPROM chip
39001090621
Rev 3.0
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Datasheet IR16x4
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MLX90621
16x4 IR array
Datasheet
7. Principle of operation
The output of all IR sensors and absolute temperature sensors is scanned according to the programmed refresh rate.
Using their output data as well as calibration constants written in EEPROM the absolute chip temperature and object
temperature, ‘seen’ by each pixel can be calculated. For this goal several sequential calculations must be done
according to the Figure 3 Operation block diagram
POR (see 8.3)
Wait 5ms
Read the EEPROM table (see 8.2.3, 9.5)
Store the calibration coefficients in the MCU RAM for fast access
Write the oscillator trim value into the IO at address 0x93 (see 7.1, 8.2.2.2, 9.4.4)
Write the configuration value (IO address 0x92) (see 8.2.2.1, 9.4.3)
The value is either read from the EEPROM or hard coded externally
Set the POR/ Brown Out flag to “1” (bit 10 at address 0x92)
Yes
POR/Brown Out flag cleared?
(see 8.2.2.1)
No
Read measurement data (PTAT + desired IR data)
(see 7.2.1, 7.2.2, 8.2.1, 9.4.2)
Calcullations (see 7.3)
Tambient calculation
Pixel offset cancelling
Thermal Gradient Compensation
Pixel to pixel normalization
Object emissivity compensation
Object temperature calculation
Image processing and correction
Figure 3 Operation block diagram
39001090621
Rev 3.0
Page 9 of 44
Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
7.1. Initialization
After the POR is released the external MCU must execute an initialization procedure.
This procedure must start at least 5ms after POR release.
- Read the whole EEPROM (see Figure 4). For maximum speed performance MELEXIS recommends that
the whole calibration data is stored into the client MCU RAM. However it is possible to read the
calibration data from the EEPROM only when needed during calculations. This will result in increased
time for temperature calculation i.e. low refresh rate.
Command
Slave address
Initial address - 0x00
SDA
S 1 0 1 0 0 0 0 W A 0 0 0
0 0 0 0
DATA(0x00)
0 A
S 1 0 1 0 0 0 0
R A
DATA(0x01)
DATA(0xFF)
A
A
NACK
Slave address
P
SCL
Figure 4 Whole EEPROM dump (SA = 0x50, command = 0x00)
-
Store the EEPROM content into customer MCU RAM – This step could be omitted resulting in more
data processing time because calibration data needs to be reread for each calculation
-
Write the oscillator trimming value (extracted from EEPROM content at address 0xF7) into the
corresponding register (0x93).
Slave address
Command
LSByte check
(LSByte - 0xAA)
SDA
S 1 1
0 0 0 0 0 W A 0 0 0 0 0 1 0 0 A
MSByte check
(MSByte - 0xAA)
LSByte data
A
A
MSByte data
A
A
P
SCL
Figure 5 Write oscillator trimming (SA = 0x60, command = 0x04)
Example: If the value that has to be uploaded is 0x0052 the following sequence must be sent:
1. Start condition (Falling edge of SDA while SCL is high)
2. Slave address (SA=0x60) plus write bit = 0xC0
3. Command = 0x04
4. LSByte check = LSByte – 0xAA = 0x52 – 0xAA = 0xA8
5. LSbyte = 0x52
6. MSByte check = MSByte – 0xAA = 0x00 – 0xAA = 0x56
7. MSbyte = 0x00
8. Stop condition (Rising edge of SDA while SCL is high)
-
Write device configuration value. In EEPROM addresses (0xF5 and 0xF6) MELEXIS provides a typical
value of the configuration register (0x463E). So it is up to the user to copy that value or hardcode a new
value to be loaded into the configuration register. If the EEPROM value is to be used the 16 bits are
combined as follows:
For example: if EEPROM 0xF5 = 0x3E and 0xF6 = 0x46, the Configuration register value is:
39001090621
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Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
Slave address
Command
LSByte check
(LSByte - 0x55)
SDA
S 1 1
0 0 0 0 0 W A 0 0 0 0 0 0 1 1 A
MSByte check
(MSByte - 0x55)
LSByte data
A
A
MSByte data
(15:11)
A
(9:8)
1
A
P
SCL
Figure 6 Write configuration register (SA = 0x60, command = 0x03)
NOTE: The user must ensure that the bit 10 (POR or Brown-out flag) in Configuration register is set to “1” by the
MD. Furthermore, this bit must be checked regularly and if it is cleared it indicates that the device has been reset
and the initialisation procedure must be redone.
Example: If the value that has to be uploaded is 0x463E the following sequence must be sent:
1. Start condition (Falling edge of SDA while SCL is high)
2. Slave address (SA=0x60) plus write bit = 0xC0
3. Command = 0x03
4. LSByte check = LSByte – 0x55 = 0x3E – 0x55 = 0xE9
5. LSbyte = 0x3E
6. MSByte check = MSByte – 0x55 = 0x46 – 0x55 = 0xF1
7. MSbyte = 0x46
8. Stop condition (Rising edge of SDA while SCL is high)
The default configuration is:
- IR and Ta refresh rate = 1Hz;
- Normal mode (no sleep);
2
- I C FM+ mode enabled (maximum bit transfer up to 1000 Kbit/s);
- ADC low reference enabled;
7.1.1. Reading configuration
7.1.1.1 Reading configuration register (EEPROM data)
Slave address
Command
Start address
Address step
Number of reads
Slave address
Configuration value
LSByte
SDA
S 1 1
0 0 0 0 0 W A 0 0 0 0 0 0 1 0 A 1 0 0 1 0 0 1 0 A 0 0 0 0 0 0 0
0 A 0 0 0 0 0 0 0 1 A
S 1 1
0 0 0 0 0 R A
Configuration value
MSByte
A
A
P
A
P
SCL
Figure 7 Reading configuration register (SA = 0x60, command = 0x02,
Start address = 0x92, Address step = 0x00, Number of reads = 0x01)
7.1.1.2 Reading oscillator trimming register (EEPROM data)
Slave address
Command
Start address
Address step
Number of reads
Slave address
Oscillator trim value
LSByte
SDA
S 1 1
0 0 0 0 0 W A 0 0 0 0 0 0 1 0 A 1 0 0 1 0 0 1 1 A 0 0 0 0 0 0 0
0 A 0 0 0 0 0 0 0 1 A
S 1 1
0 0 0 0 0 R A
Oscillator trim value
MSByte
A
SCL
Figure 8 Reading configuration register (SA = 0x60, command = 0x02,
Start address = 0x93, Address step = 0x00, Number of reads = 0x01)
39001090621
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Datasheet IR16x4
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MLX90621
16x4 IR array
Datasheet
7.2. Read measurement data (RAM data)
7.2.1. PTAT data read
Absolute ambient temperature data of the device itself (package temperature) can be read by using following
command:
Slave address
Start address
Command
Address step
Number of reads
Slave address
PTAT data
LSByte
SDA
S1 1 0 0 0 0 0 WA 0 0 0 0 0 0 1 0 A 0 1 0 0 0 0 0 0 A 0 0 0 0 0 0 0 0 A 0 0 0 0 0 0 0 1 A S1 1 0 0 0 0 0 R A
PTAT data
MSByte
A
A P
SCL
Figure 9 PTAT (SA = 0x60, command = 0x02, Start address = 0x40,
Address step = 0x00, Number of reads = 0x01) measurement result read
!
:
"
!
7.2.2. IR data read
There are four options available for reading IR data: (See section 8.2.1 for an overview of the RAM addresses).
-
Whole frame read (MELEXIS recommends the whole frame read for maximum refresh rate)
Slave address
Command
Start address
Address step
Number of reads
Slave address
SDA
S 1 1
0 0 0 0 0 W A 0 0 0 0 0
0 1 0 A 0 0 0
0 0 0 0 0 A 0 0 0 0 0
0 0 1 A 0 1 0 0 0 0 0
0 A
S 1 1
0 0 0 0 0 R A
SCL
IR pixel(0, 0)
LSByte
IR pixel(0, 0)
MSByte
A
IR pixel(1, 0)
LSByte
A
IR pixel(1, 0)
MSByte
IR pixel(3, 15)
LSByte
A
IR pixel(3, 15)
MSByte
A
A
A
P
Figure 10 Whole frame (SA = 0x60, command = 0x02, Start address = 0x00,
Address step = 0x01, Number of reads = 0x40) measurement result read
-
Single column read
Slave address
Command
Address step
Number of reads
Slave address
Start address
SDA
S 1 1
0 0 0 0
0 W A 0 0 0
0 0 0 1
0 A
A 0 0 0
0 0 0 0
1 A 0 0 0 0 0
1 0
0 A
S 1 1
0 0 0 0
0 R A
SCL
IR pixel(0, column)
LSByte
IR pixel(0, column)
MSByte
A
IR pixel(1, column)
LSByte
A
IR pixel(1, column)
MSByte
A
IR pixel(3, column)
LSByte
A
IR pixel(3, column)
MSByte
A
A
P
Figure 11 Single column (SA = 0x60, command = 0x02, Start address = 0x00…0x3C (step 0x04),
Address step = 0x01, Number of reads = 0x04) measurement result read
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16x4 IR array
Datasheet
Single line read
Slave address
Command
Address step
Number of reads
Slave address
Start address
SDA
S 1 1
0 0 0 0 0 W A 0 0 0 0 0
0 1 0 A
A 0 0 0 0 0
1 0 0 A 0 0 0 1 0 0 0
0 A
S 1 1
0 0 0 0 0 R A
SCL
IR pixel(line, 0)
LSByte
IR pixel(line, 0)
MSByte
A
IR pixel(line, 1)
LSByte
IR pixel(line, 1)
MSByte
A
IR pixel(line, 15)
LSByte
A
A
IR pixel(line, 15)
MSByte
A
A
P
Figure 12 Single line (SA = 0x60, command = 0x02, Start address = 0x00…0x03 (step 0x01),
Address step = 0x04, Number of reads = 0x10) measurement result read
-
Single pixel read
Slave address
Address step
Command
Number of reads
Slave address
IR pixel data
LSByte
Start address
SDA
S 1 1
0 0 0 0
0 W A 0 0 0
0 0
0 1
0 A
A 0 0 0
0 0
0 0
0 A 0 0 0
0 0
0 0
1 A
S 1 1
0 0 0 0
0 R A
IR pixel data
MSByte
A
A
P
SCL
Figure 13 Single pixel (SA = 0x60, command = 0x02, Start address = 0x00…0x3F,
Address step = 0x00, Number of reads = 0x01) measurement result read
-
Slave address
Compensation pixel read
Command
Start address
Address step
Number of reads
Slave address
PTAT data
LSByte
SDA
S 1 1 0 0 0 0 0 WA 0 0 0 0 0 0 1 0 A 0 1 0 0 0 0 0 1 A 0 0 0 0 0 0 0 0 A 0 0 0 0 0 0 0 1 A S1 1 0 0 0 0 0 R A
PTAT data
MSByte
A
A P
SCL
Figure 14 Compensation pixel (SA = 0x60, command = 0x02, Start address = 0x41,
Address step = 0x00, Number of reads = 0x01) measurement result read
The 16bit data for each pixel is:
#
39001090621
Rev 3.0
( , &)
#
( , &)()*+,- : #
( , &).)*+,-
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Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
7.3. Calculation
7.3.1. Calculation of absolute chip temperature Ta (sensor temperature)
The output signal of the IR sensors is relative to the cold junction temperature. That is why we need to know the
temperature of the die in order to be able to calculate the object temperature ‘seen’ by each pixel.
The Ta can be calculated using the formula:
/
Constants VTH ( 25) ,
6
0123 4 5123
0 4126 892: (25) 0
2126
=
_
4 25, 8>=
KT 1 and KT 2 are stored in EEPROM at following addresses as two’s complement values:
EEPROM address
Cell name
Stored as
Parameter
0xDA
0xDB
VTH_L
VTH_H
2’s complement
VTH0 of absolute temperature sensor
0xDC
0xDD
0xDE
0xDF
KT1_L
KT1_H
KT2_L
KT2_H
2’s complement
KT1 of absolute temperature sensor
2’s complement
KT2 of absolute temperature sensor
0xD2
KT_scale
unsigned
[7:4] – KT1_scale
[3:0] – KT2_scale
Table 5 EEPROM parameters for Ta calculations
92: (25)
256 ∗ 92:_: 4 92:_.
# 92: (25) @ 32767 → 92: (25)
92: (25)
123
92: (25)
2DEFGHIJKL-K8M:N=
256 ∗ 123_: 4 123_.
123 @ 32767 → 123
123
126
39001090621
Rev 3.0
123 0 65536
123
∗ 2DEFGHIJKL-K8M:N=
2OOLPQ( RST68U:N=
256 ∗ 126_: 4 126_.
126 @ 32767 → 126
126
92: (25) 0 65536
126
OOLPQ( RST68D:R=V3R
2
∗
126 0 65536
2DEFGHIJKL-K8M:N=
Page 14 of 44
Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
7.3.2. Example for Ta calculations
Let’s assume that the values in EEPROM are as follows
(Derived using maximum resolution – ConfigRegister[5:4] = 11b):
EEPROM address
Cell name
0xDA
0xDB
0xDC
0xDD
0xDE
0xDF
VTH_L
VTH_H
KT1_L
KT1_H
KT2_L
KT2_H
Cell values
(hex)
0x20
0x64
0x89
0x55
0x7E
0x5E
0xD2
KT_scale
0x8B
Table 6 EXAMPLE for Ta calibration values
Let’s assume that the maximum resolution is set in the configuration register:
ConfigRegister[5:4] = 11b
92: (25)
256 ∗ 100 4 32
Sign check: 25632 X 32768 → 92: (25)
92: (25)
123
256 ∗ 92:_: 4 92:_.
92: (25)
DEFGHIJKL-K8M:N=
2
256 ∗ 123Z 4 123[
25632
2DED
126
256 ∗ 85 4 137
123
∗ 2DEFGHIJKL-K8M:N=
256 ∗ 94 4 126
Sign check: 24190 X 32768 → 126
126
39001090621
Rev 3.0
_`a
6bbcdef ghia8j:g=klg ∗6jmnopqrscts8u:v=
21897
21897
21897
2] ∗ 2DED
2OOLPQ( RST68U:N=
256 ∗ 126Z 4 126[
25632
25632
Sign check: 21897 X 32768 → 123
123
25632
85.53515625
24190
24190
6N3wR
6llklg ∗6jmj
Page 15 of 44
0.01153469085
Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
Let’s assume that the input data is:
PTAT _ data = 0x67DE = 26590 dec
Thus the ambient temperature is:
a EN_ 8y
E_`l Vx_`l
`a `Z (6M)EP2z2_{/,/=
/
6_`a
E]M.MDM3M|6MV5UD3|.6|6wMNU3EN∗R.R33MDN|wR]M∗86M|D6 E6|MwR=
/
R.R6DR|wD]3U
E]M.MDM3M|6MV5UD3|.6|6wMNU3ER.RN|3D]U|DN∗(EwM])
/
R.R6DR|wD]3U
E]M.MDM3M|6MV√UD|R.N|D]wRRM
/
/
4 25
R.R6DR|wD]3U
4 25 ≈
4 25
4 25
E]M.MDM3M|6MV]M.UwD3NMwD]|
R.R6DR|wD]3U
4 25 ≈ 11.1832077 4 25
≈ 36.18 >
The calculated values for the different resolution settings are given in the table below:
ConfigRegister[5:4]
(bin)
00
PTAT data (hex)
VTH(25)
KT1
KT2
Ta, °C
0x0CFB
3323.750
10.69189453125
0.0014418363571167
36.18
01
0x19F7
6647.500
21.38378906250
0.0028836727142334
36.18
10
0x33EF
13295.000
42.76757812500
0.0057673454284668
36.18
11
0x67DE
26590.000
85.53515625000
0.0115346908569336
36.18
Table 7 Calculated values at different resolution settings
39001090621
Rev 3.0
Page 16 of 44
Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
7.3.3. Calculation of To
Following formula is used to calculate the temperature seen by specific pixel in the matrix:
Q(J,•)
Where:
v
x…
y€c(r,•)
nefdb‚ƒ„`bi
†o‡ˆ(r,•) ∗(3E_‰v ∗6UD.3M)V)h(r,•)
4
0 273.15, 8° =
/ _v
9ŠL(J,•)_FQ(PO‹)z2OT is the parasitic free IR compensated signal as calculated in 7.3.3.1
Œ•GŽ•(J,•) is the compensated sensitivity coefficient for each pixel
1•N is the compensation factor for the sensitivity – for BAB and BAD, 1•N
formula
/ _v
S(J,•)
(
/
1
4 273.15)N where
4
4
∗5
Œ‘
’“( ,&)
3
/
0, resulting in a simplified
is the ambient temperature calculated in 7.3.2
∗ 9# ( ,&)
”
•–
4 Œ‘
•—
’“( ,&)
4
∗
14
7.3.3.1 Calculating VIR(I,j)_COMPENSATED
1.
Offset compensation
9ŠL(J,•)eqq‰t˜no‡ˆtp‰™˜tš
Where:
9ŠL(J,•) 0 ›
J(J,•)
4
J(J,•)
∗(
/
0
/R )œ
9ŠL(J,•) is an individual pixel IR_data readout (RAM read)
J(J,•) is an individual pixel offset restored from the EEPROM using the following formula:
J(J,•)
∆„r
‰†™žt
z†o‡‡op V∆zr(r,•) ∗6
6jmnopqrscts8u:v=
•GŽŽGH is the minimum offset value stored in the EEPROM at addresses 0xD0 and
0xD1 as 2’s complement value
∆ J is the difference between the individual offset and the minimum value. It is stored in
the EEPROM as unsigned values.
∆ J‰†™žt is the scaling coefficient for the ∆ J values and is stored in the EEPROM at
address 0xD9[7:4] as an unsigned value
J(J,•) is an individual pixel offset slope coefficient
J(J,•)
Ÿr
*r(r,•)
bbdcef
6 ‰†™žt ∗6jmnopqrscts8u:v=
J(J,•)bbdcef is the value stored in EEPROM as two’s complements
39001090621
Rev 3.0
Page 17 of 44
Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
J‰†™žt is a scaling coefficient for the slopes of IR pixels offset and is stored in the EEPROM at
address 0xD9[3:0] as an unsigned value
/ is the ambient temperature calculated in 7.3.2
25> is a constant
/R
NOTE: This applies to the compensation pixel as well ( FP and FP while J‰†™žt is the same) with the only
difference being that FP is stored in the EEPROM at addresses 0xD3 and 0xD4 as an unsigned value but not
calculated
2.
Thermal Gradient Compensation (TGC)
9ŠL(J,•)`
nno‡ˆtp‰™˜tš
9ŠL(J,•)_QII•-,FGŽ•-H•/,-{ 0 ¡ ∗ 9ŠL••eqq‰t˜no‡ˆtp‰™˜tš
Where:
pixel
9ŠL••eqq‰t˜no‡ˆtp‰™˜tš is the offset compensated IR signal of the thermal gradient compensation
2¢Fbbdcef
¡
¡
3.
D6
OOPLQ(
is a coefficient stored at EEPROM address 0xD8 as a two’s complement value
Emissivity compensation
9ŠL(J,•)nefdb‚ƒ„`bi
y€c(r,•)
` nno‡ˆtp‰™˜tš
£
Where:
¤ is the emissivity coefficient. The scaled value is stored into EEPROM as unsigned value
6M|∗£Z V£[
¤
D6U|]
7.3.3.2 Calculating ¥¦§¨©(ª,«)
Œ•GŽ•(J,•)
¬1 4 1
∗(
/
0
/R )-
∗ ¬Œ(J,•) 0 ¡ ∗ ŒFP -
Where:
/
is the ambient temperature calculated in 7.3.2
/R
is a constant = 25°C
1
is Ta dependence of Œ•GŽ•(J,•) stored in EEPRPOM at addresses 0xE6 and 0xE7 as two’s
complement value and the scale coefficient is fixed to be 20.
1
Œ(J,•)
39001090621
Rev 3.0
6M|∗_•2/Z V_•2/[
6ag
∆¯(r,•)
au®∗¯oZ k¯g
[V
¯
a∆¯‰†™žt
a g‰†™žt
6jmnopqrscts8u:v=
Page 18 of 44
Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
6M|∗…ndZ V…nd[
¯
6 g‰†™žt ∗6jmnopqrscts8u:v=
ŒFP
ŒGZ , ŒR[ , ŒFPZ , ŒFP[ , ∆Œ(J,•) , ŒR‰†™žt and ∆Œ••/°- are stored in the EEPROM as unsigned values
7.3.3.1 Calculating ±²³
_‰v_bb
1•N
6(´‰ _‰†™žtkµ)
, stored in EEPRPOM at addresses 0x9E as two’s complement value
All parameters necessary to calculate To are stored into EEPROM at following addresses:
EEPROM
address
0x00…0x3F
Cell name
∆
J
Stored as
Parameter
unsigned
0x80…0xBF
∆Œ(J,•)
unsigned
0xC0
Ks_scale
unsigned
0xC4
1•N_OO
2’s complement
IR pixel individual offset delta coefficient
Individual Ta dependence (slope)
of IR pixels offset
Individual sensitivity coefficient
[7:4] – NA
[3:0] – Ks_scale - 8
Sensitivity To dependence (slope)
•GŽŽGH[
2’s complement
IR pixel common offset coefficient
FP[
2’s complement
Compensation pixel individual offset coefficient
2’s complement
Individual Ta dependence (slope)
of the compensation pixel offset
unsigned
Sensitivity coefficient of the compensation pixel
2’s complement
Thermal gradient coefficient
[7:4] – Scaling coeff for the IR pixels offset [3:0] –
Scaling coeff of the IR pixels offset Ta dependence
J(J,•)
0x40…0x7F
0xD0
•GŽŽGHZ
0xD1
0xD3
0xD4
FPZ
0xD5
FP
0xD6
0xD7
0xD8
0xD9
0xE0
0xE1
0xE2
0xE3
0xE4
0xE5
0xE6
0xE7
2’s complement
∆
ŒFP[
ŒFPZ
¡
J‰†™žt ,
J‰†™žt
ŒR[
ŒRZ
ŒR‰†™žt
∆Œ••/°¤.
¤:
1
.
1
:
unsigned
unsigned
Common sensitivity coefficient of IR pixels
unsigned
Scaling coefficient for common sensitivity
unsigned
Scaling coefficient for individual sensitivity
unsigned
Emissivity
2’s complement
KsTa (fixed scale coefficient = 20)
Table 8 EEPROM parameters for To calculations
39001090621
Rev 3.0
Page 19 of 44
Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
7.3.4. Example for To calculations
Let’s assume that we have following EEPROM data for pixel i=2, j=8:
EEPROM
address
0x22
0x62
0xA2
Cell name
∆
J
J(J,•)
Stored as
Cell values (hex)
unsigned
0x21
0xBC
0xCD
0x99
0x9E
0x8A
0xFF
0x9D
0xFF
0xA2
0xA8
0x0F
0x18
0x07
0xAE
0x4E
0x26
0x1F
0x00
0x80
0x0C
0x02
2’s complement
∆Œ(J,•)
unsigned
0xC0
0xC4
Ks_scale
0xD0
•GŽŽGH[
2’s complement
FP[
2’s complement
0xD1
0xD3
0xD4
0xD5
0xD6
0xD7
0xD8
0xD9
0xE0
0xE1
0xE2
0xE3
0xE4
0xE5
0xE6
0xE7
unsigned
2’s complement
1•N
•GŽŽGHZ
FPZ
FP
ŒFP[
ŒFPZ
¡
∆ J‰†™žt , J‰†™žt
ŒR[
ŒRZ
ŒR‰†™žt
∆Œ••/°¤.
¤:
1
.
1
:
2’s complement
unsigned
2’s complement
unsigned
unsigned
unsigned
unsigned
unsigned
2’s complement
Table 9 EXAMPLE for To calibration values
Let’s assume that we have the following input data:
9ŠL(6,])
0 01 7
439, decimal value
Sign check 439 X 32768 → 9ŠL(6,])
9FP
0
—
65500, decimal value (compensation pixel readings)
Sign check 65500 @ 32767 → 9FP
/
439 LSB
65500 0 65536
036 LSB
≈ 36.18 > (as calculated in 7.3.2)
39001090621
Rev 3.0
Page 20 of 44
Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
Reference routine for To computation:
v
x…
Q(J,•)
y€c(r,•)
nefdb‚ƒ„`bi
†o‡ˆ(r,•) ∗(3E_‰v ∗6UD.3M)V)h
9ŠL(6,])eqq‰t˜no‡ˆtp‰™˜tš
9ŠL(6,]) 0 ›
z†o‡‡op V∆zr(a,µ) ∗6
J(6,])
4
J(6,])
4
J(6,])
∗(
/
0
/R )œ
∆„r
‰†™žt
6(jmnopqrscts8u:v=)
256 ∗
•GŽŽGH
•GŽŽGHZ
4
256 ∗ 255 4 138
•GŽŽGH[
Sign check 65418 @ 32767 →
∆
0 273.15, 8° =
/ _v
65418 LSB decimal value
65418 0 65536
•GŽŽGH
0118 LSB
33 LSB
J
z†o‡‡op V∆zr(a,µ) ∗6
J(6,])
∆„r
‰†™žt
E33]VDD∗6g
6(jmnopqrscts8u:v=)
*r(a,µ)
J(6,])
Ÿ
6 r‰†™žt ∗6(jmnopqrscts8u:v=)
188
J(6,])_OO
Sign check 188 @ 127 →
J(6,])
6
Ÿr
*r(a,µ)
256 ∗
FPZ
4
188 0 256
J(6,])
E|]
439 0 ¬085 0 0.53125 ∗ (36.18 0 25)- ≈ 529.939375 LSB
FP[
65437 , decimal value
Sign check 65437 @ 32768 →
znd
FP
6(jmnopqrscts8u:v=)
FP_OO
Eww
6(jmj)
65437 0 65536
FP
099 LSB
099
162
Sign check 162 @ 127 →
*nd
Ÿ
6 r‰†™žt ∗6(jmnopqrscts8u:v=)
FP
068
00.53125
6· ∗6(jmj)
‰†™žt ∗6(jmnopqrscts8u:v=)
9ŠL(6,])eqq‰t˜no‡ˆtp‰™˜tš
FP
085 LSB
6(jmj)
9ŠLFPeqq‰t˜no‡ˆtp‰™˜tš
9FP 0 ¬
162 0 256
FP
EwN
6· ∗6(jmj)
FP
4
FP
094
00.734375
∗(
/
0
/R )-
036 0 (099 0 0.734375 ∗ (36.18 0 25))
9ŠLFPeqq‰t˜no‡ˆtp‰™˜tš ≈ 71.2103125 LSB
¡
OOPLQ(
0 18
24, decimal value
Sign check 24 X 128 → ¡ _••
39001090621
Rev 3.0
”
24
Page 21 of 44
Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
2¢Fbbdcef
¡
6N
D6
0.75
D6
9ŠL(6,])`
nno‡ˆtp‰™˜tš
9ŠL(6,])_QII•-,FGŽ•-H•/,-{ 0 ¡ ∗ 9ŠL••eqq‰t˜no‡ˆtp‰™˜tš
9ŠL(6,])`
nno‡ˆtp‰™˜tš
529.939375 0 0.75 ∗ 71.2103125 ≈ 475.531640625 LSB
6M|∗£Z V£[
¤
D6U|]
6M|∗36]VR
1
∗(
¬1 4 1
256 ∗ 1
:
1
D6U|]
y€c(a,µ)
9ŠL(6,])nefdb‚ƒ„`bi
Œ•GŽ•(6,])
D6U|]
D6U|]
£
/
41
/R )-
0
M6N
au®∗¯oZ k¯g[ ∆¯(a,µ)
V ∆¯
¯
a ‰†™žt
a g‰†™žt
6M|∗…ndZ V…nd[
¯
6 g‰†™žt ∗6jmnopqrscts8u:v=
Œ•GŽ•(6,])
6M|∗3MV3|]
NRR]
6jµ ∗6(jmj)
6jµ
≈ 1.68736733031.10EU
≈ 1.45810190588.10E]
1.58682591595. 10EU
158 decimal value
Sign check 158 @ 127 → 1•N
_‰v
1•N
6(´‰ _‰†™žtkµ)
(
/ _v
/
Ew]
098
07.476806640625. 10EN
6(¸kµ)
4 273.15)N
158 0 256
(36.18 4 273.15)N
9155628583
v
1)N ∗ xŒ•GŽ•(6,]) D ∗ 9ŠL(6,])nefdb‚ƒ„`bi 4 Œ•GŽ•(6,]) N ∗
S
S
aglva agu
V
ajµ ajl
6(jmj)
¬1 4 4.9972534.10EN ∗ (36.18 0 25)- ∗ (1.68736733031.10EU 0 0.75 ∗ 1.45810190588.10E] )
Œ•GŽ•(6,])
1•N
524 LSB
FP
au®∗·µkl·v agu
V jl
ajµ
a
6(jmj)
6(jmnopqrscts8u:v=)
ŒFP
524 , decimal value
4.9972534.10EN decimal value
6ag
Œ(6,])
∗ ¬Œ(6,]) 0 ¡ ∗ ŒFP -
256 ∗ 2 4 12
.
Sign check 524 @ 32768 →
1
476.531640625 LSB
` nno‡ˆtp‰™˜tš
/ _v
07.476806640625. 10EN ∗ 5(1.58682591595. 10EU )D ∗ 476.531640625 4 (1.58682591595. 10EU )N ∗ 9155628583
S
v
03.93973510355. 10E]
v
x…
Q(6,])
Q(6,])
Q(6,])
39001090621
Rev 3.0
y€c(a,µ)
nefdb‚ƒ„`bi
†o‡ˆ(a,µ) ∗(3E_‰v ∗6UD.3M)V)h
4
/ _v
0 273.15 °C
NU|.MD3|NR|6M
x3.M]|]6Mw3MwM.3Rm·∗(3E(EU.NU|]R||NR|6M.3Rmv)∗6UD.3M)V(ED.wDwUDM3RDMM.3Rmµ) 4 9155628583 0 273.15 °C
v
59.8546263694257 ≈ 59.85 °C
Page 22 of 44
Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
The calculated values for the different resolution settings are given in the table below:
ConfigRegister[5:4] (bin)
¹º»(¼,½)
¹¾¿
¹º»(¼,½)¾ÀÁ¿ÂÃÄÅÆÂÇ
¥¦§¨©(¼,½)
ÄÈ
To, °C
00
0x0036
0xFFFB
59.066455078125
1.98353239494464E-08
-4.9221144181793E-09
59.67
01
0x006D
0xFFF7
118.38291015625
3.96706478988929E-08
-9.8455068127298E-09
59.72
10
0x00DB
0xFFEE
237.7658203125
7.93412957977857E-08
-1.9696122547076E-08
59.81
11
0x01B7
0xFFDC
476.531640625
1.58682591595571E-07
-3.9397351035512E-08
59.85
Table 10 Calculated values at different resolution settings
8. Detailed description, Block description
8.1. Pixel position
The array consists of 64 IR sensors (also called pixels). Each pixel is identified with its row and column position as
Pix(i,j) where i is its row number (from 0 to 3) and j is its column number (from 0 to 15)
Reference pin
Row 0
Row 1
Row 2
Col 15
Col 14
Col 13
Col 12
Col 11
Col 10
Col 9
Col 8
Col 7
Col 6
Col 5
Col 4
Col 3
Col 2
Col 1
Col 0
Row 3
Figure 15 Pixel position in the whole FOV
39001090621
Rev 3.0
Page 23 of 44
Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
8.2. MLX90621 address map
The MLX90621 address map is shown below:
0x00
RAM
0x41
0x42
Not used
0x91
0x92
0x93
0x93
Configuration registers
Not used
0xFF
Figure 16 Address map
8.2.1. RAM
2
The on chip 146x16 RAM is accessible for reading via I C. The RAM is used for storing the results of measurements of
pixels and Ta sensor and is distributes as follows:
• 64 words for IR sensors. The data is in 2’s complement format (see 7.2.2)
• 1 word for measurement result of PTAT sensor. The data is 16 bit without sign. (see 7.2.1)
The memory map of the RAM is shown below:
RAM Address
0x00
0x01
0x02
0x03
0x04
0x05
…
0x3B
0x3C
0x3D
0x3E
0x3F
0X40
0x41
RAM variable description
IR sensor (0,0) result
IR sensor (1,0) result
IR sensor (2,0) result
IR sensor (3,0) result
IR sensor (0,1) result
IR sensor (1,1) result
…
IR sensor (3,14) result
IR sensor (0,15) result
IR sensor (1,15) result
IR sensor (2,15) result
IR sensor (3,15) result
PTAT sensor result
Compensation pixel result
Table 11: Result address map
For IR sensors results, the addressing can be summarized:
IR(x,y) is on address:
IR( x, y)address = x + 4. y
39001090621
Rev 3.0
Page 24 of 44
Datasheet IR16x4
15 September 2016
MLX90621
16x4 IR array
Datasheet
8.2.2. Internal registers
8.2.2.1 Configuration register (0x92)
The configuration register defines the chip operating modes.
2
It can be read and written by the I C MD.
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Configuration register bit meaning (0x92)
0
0
0
0 - IR Refresh rate = 512Hz
0
0
0
1 - IR Refresh rate = 512Hz
0
0
1
0 - IR Refresh rate = 512Hz
0
0
1
1 - IR Refresh rate = 512Hz
0
1
0
0 - IR Refresh rate = 512Hz
0
1
0
1 - IR Refresh rate = 512Hz
0
1
1
0 - IR Refresh rate = 256Hz
0
1
1
1 - IR Refresh rate = 128Hz
1
0
0
0 - IR Refresh rate = 64Hz
1
0
0
1 - IR Refresh rate = 32Hz
1
0
1
0 - IR Refresh rate = 16Hz
1
0
1
1 - IR Refresh rate = 8Hz
1
1
0
0 - IR Refresh rate = 4Hz
1
1
0
1 - IR Refresh rate = 2Hz
1
1
1
0 - IR Refresh rate = 1Hz (default)
1
1
1
1 - IR Refresh rate = 0.5Hz
0
0 ADC set to 15 bit resolution*1
0
1 ADC set to 16 bit resolution*1
1
0 ADC set to 17 bit resolution*1
1
1 ADC set to 18 bit resolution*1
0 - Continuous measurement mode (default)
1 - Step mode
- Normal operation mode (default)
- Sleep mode
0
0
1
x - NA
0 - No IR measurement running (flag only cannot be written)
1 - IR measurement running (flag only cannot be written)
0
- POR or Brown-out occurred - Need to reload Configuration register
1
- MD must write "1" during uploading Configuration register (default)
0
- I2C FM+ mode enabled (max bit transfer rates up to 1000 kbit/s) (default)
1
- I2C FM+ mode disabled (max bit transfer rates up to 400 kbit/s)
0
- EEPROM enabled
1
- EEPROM disabled
0
- Melexis reserved
0
- ADC high reference enabled*2
1
- ADC low reference enabled (default)
- Melexis reserved
Table 12: Configuration register bit meaning
*1 – does not impacting the calibration of the device (may be changed and the calibration remain valid)
*2 – does impact the calibration of the device (if changed the calibration is no longer valid)
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16x4 IR array
Datasheet
8.2.2.2 Trimming register (0x93)
2
It can be read and written by the I C MD.
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
7 bit value
x
x
x
x
x
x
x
x
x
Trimming register bit meaning (0x93)
- Oscillator trim value
NA
Table 13 Oscillator trim bit meaning
8.2.3. EEPROM
2
A 2kbit, organized as 256x8 EEPROM is built in the Mlx90621. The EEPROM has a separate I C address SA=0x50 and is
used to store the calibration constants and the configuration of the device.
Address
00
08
10
18
20
28
30
38
40
48
50
58
60
68
70
78
80
88
90
98
A0
A8
B0
B8
C0
C8
D0
D8
E0
E8
F0
F8
0
ΔAi (0,0)
1
ΔAi (1,0)
2
ΔAi (2,0)
3
ΔAi (3,0)
4
ΔAi (0,1)
5
ΔAi (1,1)
6
ΔAi (2,1)
7
ΔAi (3,1)
ΔAi (2,15)
Bi (2,1)
ΔAi (3,15)
Bi (3,1)
Bi (2,15)
Δα (2,1)
Bi (3,15)
Δα (3,1)
…
ΔAi - IR pixels individual offset coefficients
…
ΔAi (0,14)
Bi (0,0)
ΔAi (1,14)
Bi (1,0)
ΔAi (2,14)
Bi (2,0)
ΔAi (3,14)
Bi (3,0)
ΔAi (0,15)
Bi (0,1)
ΔAi (1,15)
Bi (1,1)
…
Bi - Individual Ta dependence (slope) of IR pixels offset
…
Bi (0,14)
Δα (0,0)
Bi (1,14)
Δα (1,0)
Bi (2,14)
Δα (2,0)
Bi (3,14)
Δα (3,0)
Bi (0,15)
Δα (0,1)
Bi (1,15)
Δα (1,1)
…
Individual sensitivity coefficients
…
Δα (3,14)
Δα (0,15)
Δα (1,15)
Δα (2,15)
Δα (3,15)
Δα (0,14)
Δα (1,14)
Δα (2,14)
Ks_scales
reserved
reserved
reserved
reserved
reserved
reserved
1•N
reserved
reserved
reserved
reserved
reserved
reserved
reserved
A common
KT scale
Compensation pixel coefficients
TGC
PTAT
Scale offset
KsTaL
KsTaH
Common sensitivity coefficients
Emissivity
MELEXIS reserved
MELEXIS reserved
Configuration register
OSC trim
Chip ID
Table 14: EEPROM map
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16x4 IR array
Datasheet
Detailed descriptions of some of the EEPROM addresses are described here after:
C7
C6
C5
C4
C3
C2
C1
C0
EEPROM cell meaning
Ks_scale
[7:4] - reserved
[3:0] - Ks_scale - 8
- MLX reserved
Table 15: C0…C7 EEPROM cell meaning
D7
ΔαCP_H
D6
ΔαCP_L
D5
D4
D3
D2
D1
D0
EEPROM cell meaning
AcommonH AcommonL - common offset
KT scale
[7:4] - KT1 scale
[3:0] - KT2 scale -10
ACPH
ACPL
- Compensation pixel individial offset
BCP
- Individual Ta dependence (slope) of the compensation pixel offset
- Sensitivity coefficient of the compensation pixel
Table 16: D0…D7 EEPROM cell meaning
DF
DE
DD
DC
DB
Vth_H
KT2_H
KT2_L
DA
Vth_L
D9
D8
EEPROM cell meaning
TGC
- Thermal Gradien Coefficient
Offset scale
[7:4] - Aiscale
[3:0] - Biscale
- Vth0 of absolute temperatire sensor
KT1_H
KT1_L
- KT1 of absolute temperature sensor
- Kt2 of absolute temperatire sensor
Table 17: DF…D8 EEPROM cell meaning
E7
E6
E5
E4
E3
E2
α0_scale
ε_H
MELEXIS reserved
ε_L
E1
E0
EEPROM cell meaning
α0_H
α0_L
- Common sensitivity coefficient
- Common sensitivity scaling coefficient
Δαscale
- Individual sensitivity scaling coefficient
- Emissivity coefficient
- MELEXIS reserved
Table 18: E7…E0 EEPROM cell meaning
F7
F6
F5
F4
F3
F2
F1
MELEXIS reserved
CFG_H
OSC_trim
CFG_L
F0
EEPROM cell meaning
- MELEXIS reserved
- Config register value
- Oscillator trimming value
Table 19: F7…F0 EEPROM cell meaning
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16x4 IR array
Datasheet
8.3. POR
The Power On Reset (POR) is connected to the Vdd supply. The on-chip POR circuit provides an active level of the
POR signal when the Vdd voltage rises above approximately 0.5V and holds the entire Mlx90621 in reset until the
Vdd is higher than 2.4V. The device will start approximately 5ms after the POR release.
8.4. ESD
ESD, 4KV Human Body Model (please check with electrical specification)
9. Communication protocol
2
The device supports Fast Mode Plus I C FM+ (IR array only up to 1MHz while the EEPROM can handle only up to 400
kHz) and will work in slave mode only.
The master device must provide the clock signal (SCL) for the communication. The data line SDA is bidirectional and
is driven by the master or the slave depending on the command. The selection of the SDA occupant is done
2
according to the I C specification. As the SDA is an open-drain IO, ‘0’ is transmitted by forcing the line ‘LOW’ and a
‘1’ just by releasing it. During data transfer, the data line could be changed only while SCL is low. Otherwise, it would
be interpreted as a start/stop condition
9.1. Communication pins
There are two communication pins SCL and SDA. SCL is an input only for the MLX90621 while the SDA pin is a
bidirectional one. The SDA line should be wired in an open-drain configuration.
90620
90621
90670
scl_in
sda_out
90670
Digital
Block
+VDD
external
sda_in
Rp
SCL
SDA
Rp
SCL
SCL (Serial Clock Line )
SDA
SDA (Serial data Line )
24AA02
External I2C
Master
Figure 17 Communication pin diagram
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16x4 IR array
Datasheet
9.2. Low level communication protocol
9.2.1. Start / Stop condition
Each communication session is initiated by a START condition and ends with a STOP condition. A START condition is
initiated by a HIGH to LOW transition of the SDA while a STOP is generated by a LOW to HIGH transition. Both
changes must be done while the SCL is HIGH (see the figure)
SCL
SDA
START
STOP
2
Figure 18: Start / Stop conditions of I C
9.2.2. Device addressing
The master is addressing the slave device by sending a 7-bit slave address after the START condition. The first seven
th
bits are dedicated for the address and the 8 is Read/Write (R/W) bit. This bit indicates the direction of the transfer:
• Read (HIGH) means that the master will read the data from the slave
• Write (LOW) means that the master will send data to the slave
Mlx90621 is responding to 2 different slave addresses:
1
0
1
0
0
0
0
R/W
for access to internal EEPROM
1
1
0
0
0
0
0
R/W
For access to IR array data
2
Figure 19: I C addresses
9.2.3. Acknowledge
th
During the 9 clock following every byte transfer the transmitter releases the SDA line. The receiver acknowledges
(ACK) receiving the byte by pulling SDA line to low or does not acknowledge (NoACK) by letting the SDA ‘HIGH’.
9.2.4. Low level communication operation
The low level operation communication is based on 8bits (1byte) transmissions. This includes start/stop event,
acknowledgement and errors detection.
I2C
transmission
S
T
A
R
T
8 Bits
A
C
K
S
T
O
P
2
Figure 20: I C communication
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16x4 IR array
Datasheet
9.3. Device modes
The device can operate in following modes:
• Normal mode
• Step mode
• Power saving mode
9.3.1. Normal mode
In this mode the measurements are constantly running. Depending on the selected frame rate Fps in the
configuration register, the data for IR pixels and Ta will be updated in the RAM each 1/Fps seconds. In this mode the
external microcontroller has full access to the internal registers and memories of the device (both for 90670 and the
EEPROM chip).
9.3.2. Step mode
This mode is foreseen for single measurements triggered by an external device (microcontroller). Entering this mode
is possible by writing the appropriate code in the configuration register. A measurement is triggered by sending the
command StartMeas (see 9.4.1). On detecting the command, the Mlx90621 will start the measurements
2
immediately after the I C session is finished (STOP condition detected).
3
Ɉ‰
The measurement time is
While the Step mode measurement is ongoing all ‘start new measurement in step mode’ commands will be
acknowledged but not executed. All other valid commands are executed accordingly.
A flag bit in Configuration register (bit 0x09) is dedicated in order to be able to check whenever the measurement is
done.
Slave address
Start Meas
Command
SDA
S 1 1
0 0 0 0 0 W A 0 0 0 0 0 0 0 1 A 0 0 0
0 1 0 0 0 A
P
SCL
Figure 21 Write configuration register (SA = 0x60, command LSByte = 0x01 command MSByte = 0x08)
9.3.3. Power saving mode
In this mode the device will be completely shut down and the current consumption will be minimized to less than
6µA. Entering this mode is initiated by writing ‘1’ in the configuration register bit 7. Upon receiving it the device will
2
shut down all electronics, including the internal oscillator. The chip will monitor the I C line. Each START condition
will wake up the oscillator and the chip will receive and evaluate the slave address. If the address is 0x60 (address
programmed in Mlx90621) the device will evaluate the whole command and will execute it. If not, the oscillator will
be switched off again.
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16x4 IR array
Datasheet
9.4. Communication to IR array
9.4.1. Start measurement command
Opcode – 0x01 (LSByte), 0x08 (MSByte).
This command is used to start measurement cycle in step mode.
Start Meas
LSByte Opcode
Slave address
S
T
A
R
T
0 A
C
K
Start Meas
MSByte Opcode
A
C
K
A
C
K
S
T
O
P
Figure 22: Start measurement command structure
9.4.2. Read command
Opcode – 0x02.
The read command is used to read measurement, configuration and other data from the chip to the external master.
The read command has the following parameters:
- Start address – 8bits. Address in the chip address space (0 to 255). It is the address of the first word read.
- Address step – 8bits. On every read word the next address is formed by adding the address step to the current
address.
- Number of reads – 8bits. Number of the words to be read.
Different combinations are possible in order to read all, one line, one column, one exact pixel of the IR or Ta sensors.
They are summarized in the table below:
Sensors read
All IR
One line IR(i)
One column IR(j)
One pixel IR(i,j)
Start address
0x00
i
j*0x04
I + j*0x04
Address step
0x01
0x04
0x01
0x00
Number of reads
0x40
0x10
0x04
0x01
Table 20 RAM readout options
S
T
A
R
T
Slave address
0 A
C
K
Start address
parameter
Read Opcode
A
C
K
Address step
parameter
A
C
K
Number reads
parameter
A
C
K
Read Word0
LSByte
Slave address
A
C
K
S
T
A
R
T
1
A
C
K
Read Word0
MSByte
A
C
K
Read WordN
LSByte
A
C
K
Read WordN
MSByte
A
C
K
A
C
K
S
T
O
P
Read N 16bit words
Figure 23: RAM readout command structure
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16x4 IR array
Datasheet
9.4.3. Write configuration register command
Opcode – 0x03.
This command is used to set the configuration register (16bits) value – all configuration settings.
Each data byte is transmitted in two stages:
- First stage Data byte - 0x55
- Second stage Data byte
This way of transmitting the data is done in order to have a simple error check.
The chip adds 0x55 to the first byte and compares the result with the second one. If both match the configuration
register is updated.
Figure 24: Configuration register update command structure
9.4.4. Write trimming command
Opcode – 0x04.
This command is used to set the oscillator trimming oscillator trimming value.
This command is used to set the oscillator trimming register (16bits) value.
Each data byte is transmitted in two stages:
- First stage Data byte - 0xAA
- Second stage Data byte
This way of transmitting the data is done in order to have a simple error check.
The chip adds 0xAA to the first byte and compares the result with the second one. If both match the oscillator
trimming register is updated.
S
T
A
R
T
Slave address
0 A
C
K
Write trimming
opcode
Trimming data check
LSByte
A
C
K
Trimming data
LSByte
A
C
K
Trimming data check
MSByte
A
C
K
A
C
K
Trimming data
MSByte
A
C
K
S
T
O
P
Figure 25: Oscillator trimming register update command structure
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16x4 IR array
Datasheet
9.5. Communication to EEPROM
See datasheet of 24AA02. This can be found at
https://www.melexis.com/en/product/mlx90621/far-infrared-sensor-array-high-speed-low-noise
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16x4 IR array
Datasheet
10. Performance Graphs
10.1. Temperature accuracy of the MLX90621
All accuracy specifications apply under settled isothermal conditions only.
Furthermore, the accuracy is only valid if the object fills the FOV of the sensor completely.
To, °C
200°C
100°C
±4°C ±3% * |To-Ta|
(Uniformity ±1°C ±1.5%*|To-Ta|)
300°C
±1°C ±3% * |To-Ta|
(Uniformity ±1°C ±1.5%*|To-Ta|)
±2.5°C ±3%* |To-Ta|
(Uniformity ±1°C
±1.5%* |To-Ta|)
Ta, °C
0°C
-20°C
-20°C
±5.5°C
±3°C ±5% * |To-Ta|
±4°C ±5% * |To-Ta|
50°C
0°C
85°C
Figure 26: Absolute temperature accuracy for the central four pixels
All accuracy specifications apply under settled isothermal conditions only.
NOTE:
1) The accuracy is specified for the four central pixels. The accuracy of the rest of the pixels is according to the
uniformity statement
2) As a result of long term (years) drift there can be an additional measurement deviation of ± 3°C for object
temperatures around room temperature.
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16x4 IR array
Datasheet
10.2. Noise performance and resolution
There are two bits in the configuration register that allow changing the resolution of the MLX90621 measurements.
Increasing the resolution decreases the quantization noise and improves the overall noise performance.
Measurement conditions for the noise are: To=Ta=25°C
NOTE: It is normal that the noise will decrease for high temperature and increase for lower temperatures
3.00
Central pixels RMS noise at different refresh rates and
maximum resolution (Configuration register[5:4] = 11b)
Noise, °C
2.50
MLX90621BAA (120°X25°)
MLX90621BAB (60°X15°)
MLX90621BAD (40°X10°)
2.00
1.50
1.00
0.50
0.00
0.5
1
2
4
8
16
32
Refresh rate, Hz
64
128
256
512
Figure 27: Central pixels noise
6.00
Corner pixels RMS noise at different refresh rates and
maximum resolution (Configuration register[5:4] =
11b)
Noise, °C
5.00
MLX90621BAA (120°X25°)
MLX90621BAB (60°X15°)
MLX90621BAD (40°X10°)
4.00
3.00
2.00
1.00
0.00
0.5
1
2
4
8
16
32
Refresh rate, Hz
64
128
256
512
Figure 28: Corner pixels noise
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16x4 IR array
Datasheet
The higher resolution limits the maximum object temperature range of the MLX90621.
Configuration register[5:4],
bin
Resolution
00
01
10
11
15 bits
16 bits
17 bits
18 bits
Maximum object temperature,
°C
BAA
BAB
BAD
~750
~950
~1100
~550
~750
~900
~450
~600
~700
~320
~450
~500
Table 21 Maximum object temperature at different resolution settings
NOTE: If object temperature exceeds the maximum object temperature specified for the corresponding resolution,
the MLX90621 may return invalid data due to measurements overflow.
10.3. Field Of View (FOV)
Point heat source
Sensitivity
100%
50%
Field Of View
Angle of incidence
Rotated sensor
Figure 29: Field Of View measurement
The specified FOV is calculated for the wider direction, in this case for the 16 pixels.
Angular alignment must be 5% of specified FOV and will be valid for both directions. For example for the 60° FOV in
the wider direction will come with 16° in the shorter direction.
FOV
MLX90621-ESF-BAA
MLX90621-ESF-BAB
MLX90621-ESF-BAD
X direction
Typ
120
60
40
Y direction
Typ
25
16
10
Table 22 Available FOV options
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16x4 IR array
Datasheet
11. Applications Information
11.1. Use of the MLX90621 thermometer in I2C configuration
MCU VDD = 2.5...5V
VDD
SENSOR VDD = 2.6V
VDD1
2 - SDA
3 - VDD
1 - SCL
4 - VSS
MCU
2
Figure 30: MLX90621 I C connection
2
As the MLX90621xxx is fully I C compatible it allows to have a system in which the MCU may be supplied with
VDD=2.5…5V while the sensor it’s self is supplied from separate supply VDD1=2.6V (or even left with no supply i.e.
2
VDD=0V), with the I C connection running at supply voltage of the MCU.
12. Application Comments
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.
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 MLX90621xxx, it is recommended not to
subject the MLX90621 to heat transfer and especially transient conditions.
The MLX90621 is designed and calibrated to operate as a non-contact thermometer in settled conditions.
Using the thermometer in a very different way will result in unknown results.
2
Capacitive loading on an I C 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. With the MLX90621 additional improvement is possible by increasing the pull-up current
2
(decreasing the pull-up resistor values). Input levels for I C compatible mode have higher overall tolerance than the
2
2
I C specification, but the output low level is rather low even with the high-power I C specification for pull-up
currents. Another option might be to go for a slower communication (clock speed), as the MLX90621 implements
2
Schmidt triggers on its inputs in I C compatible mode and is therefore not really sensitive to rise time of the bus (it is
2
more likely the rise time to be an issue than the fall time, as far as the I C systems are open drain with pull-up).
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16x4 IR array
Datasheet
Power dissipation within the package may affect performance in two ways: by heating the “ambient” sensitive
element significantly beyond the actual ambient temperature, as well as by causing gradients over the package that
will inherently cause thermal gradient over the cap
Power supply decoupling capacitor is needed as with most integrated circuits. MLX90621 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 100nF 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. Using
MLX90621 with short pins improves the effect of the power supply decoupling.
Check www.melexis.com for most recent application notes about MLX90621.
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16x4 IR array
Datasheet
13. Standard information regarding
manufacturability of Melexis products with
different soldering processes
Our products are classified and qualified regarding soldering technology, solderability and moisture sensitivity level
according to following test methods:
Wave Soldering THD’s (Through Hole Devices)
• 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 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.
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
The MLX90621 is RoHS compliant
14. ESD Precautions
Electronic semiconductor products are sensitive to Electro Static Discharge (ESD).
Always observe Electro Static Discharge control procedures whenever handling semiconductor products.
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16x4 IR array
Datasheet
15. FAQ
When I measure aluminum and plastic parts settled at the same conditions I get significant errors on aluminum.
Why?
Different materials have different emissivity. A typical value for aluminum (roughly polished) is 0.18 and for plastics
values of 0.84…0.95 are typical. IR thermometers use the radiation flux between the sensitive element in the sensor
and the object of interest, given by the equation
Ê
Where:
¤1 ∗ Œ1 ∗
4
1
∗Ë∗
1
∗
0Ì
0 ¤2 ∗
4
2
∗Ë∗
2
¤3 and ¤6 are the emissivity of the two objects
Œ3 is the absorptivity of the sensor (in this case),
Ë is the the Stefan-Boltzmann constant,
3
and
zE*
6
are the surface areas involved in the radiation heat transfer,
is the shape factor,
ÆÍ and Ƽ are known temperature of the sensor die (measured with specially integrated and calibrated element)
and the object temperature that we need.
Note that the temperatures are all in Kelvin, heat exchange knows only physics.
When a body with low emissivity (such as aluminum) is involved in this heat transfer, the portion of the radiation
incident to the sensor element that really comes from the object of interest decreases – and the reflected
environmental IR emissions take place. (This is all for bodies with zero transparency in the IR band.) The IR
thermometer is calibrated to stay within specified accuracy – but it has no way to separate the incoming IR radiation
into real object and reflected environmental part. Therefore, measuring objects with low emissivity is a very
sophisticated issue and infra-red measurements of such materials are a specialized field.
What can be done to solve that problem? Look at paintings – for example, oil paints are likely to have emissivity of
0.85…0.95 – but keep in mind that the stability of the paint emissivity has inevitable impact on measurements.
It is also a good point to keep in mind that not everything that looks black is “black” also for IR. For example, even
heavily oxidized aluminum has still emissivity as low as 0.30.
How high is enough? Not an easy question – but, in all cases the closer you need to get to the real object
temperature the higher the needed emissivity will be, of course.
With the real life emissivity values the environmental IR comes into play via the reflectivity of the object (the sum of
Emissivity, Reflectivity and Absorptivity gives 1.00 for any material). The larger the difference between
environmental and object temperature is at given reflectivity (with an opaque for IR material reflectivity equals 1.00
minus emissivity) the bigger errors it produces.
After I put the MLX90621 in the dashboard I start getting errors larger than specified in spite that the module was
working properly before that. Why?
Any object present in the FOV of the module provides IR signal. It is actually possible to introduce error in the
measurements if the module is attached to the dashboard with an opening that enters the FOV. In that case portion
of the dashboard opening will introduce IR signal in conjunction with constraining the effective FOV and thus
compromising specified accuracy. Relevant opening that takes in account the FOV is a must for accurate
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measurements. Note that the basic FOV specification takes 50% of IR signal as threshold (in order to define the area,
where the measurements are relevant), while the entire FOV at lower level is capable of introducing lateral IR signal
under many conditions.
When a hot (cold) air stream hits my MLX90621 some error adds to the measured temperature I read. What is it?
IR sensors are inherently sensitive to difference in temperatures between the sensitive element and everything
incident to that element. As a matter of fact, this element is not the sensor package, but the sensor die inside.
Therefore, a thermal gradient over the sensor package will inevitably result in additional IR flux between the sensor
package and the sensor die. This is real optical signal that cannot be segregated from the target IR signal and will add
errors to the measured temperature.
Thermal gradients with impact of that kind are likely to appear during transient conditions. The sensor used is
developed with care about sensitivity to this kind of lateral phenomena, but their nature demands some care when
choosing place to use the MLX90621 in order to make them negligible.
I measure human body temperature and I often get measurements that significantly differ from the +37°C I
expect.
IR measurements are true surface temperature measurements. In many applications this means that the actual
temperature measured by an IR thermometer will be temperature of the clothing and not the skin temperature.
Emissivity (explained first in this section) is another issue with clothes that has to be considered.
There is also the simple chance that the measured temperature is adequate – for example, in a cold winter human
hand can appear at temperatures not too close to the well-known +37°C.
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16. Mechanical specification
16.1. Package outline
The height of the can depends on the selected FOV of the array
Figure 31 Overview of the different device FOV options
Figure 32 Mechanical drawing of Wide (120x25) FOV device (MLX90621BAA)
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Figure 33 Mechanical drawing of Wide (60x16) FOV device (MLX90621BAB)
Figure 34 Mechanical drawing of Medium (40x10) FOV device (MLX90621BAD)
16.2. Part marking
The MLX90621 is laser marked with 10 symbols. The first is a 1, the next 3 letters indicate the version (BAA, BAB or
BAD) and the remaining 7 indicate the lot number.
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17. References
2
[1] I C-bus specification and user manual Rev. 03 — 19 June 2007
http://www.nxp.com/documents/user_manual/UM10204.pdf
18. Disclaimer
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, 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.
© 2015 Melexis NV. All rights reserved.
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:
Phone: +32 1367 0495
E-mail: sales_europe@melexis.com
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Phone: +1 248 306 5400
E-mail: sales_usa@melexis.com
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