Data Sheet
MLX90640 32x24 IR array
Datasheet
Page 38 of 60
REVISION 11 – 3 AUGUST 2018
Please note that this value is updated every frame and it is the same for all pixels including CP regardless the subpage
number
11.2.2.5.
11.2.2.5.11.2.2.5.
11.2.2.5. Pixel data calculations
Pixel data calculationsPixel data calculations
Pixel data calculations
The pixel addressing is following the pattern as described in Reading pattern shown in Fig 5:
11.2.2.5.1.
11.2.2.5.1.11.2.2.5.1.
11.2.2.5.1. Gain compensation
Gain compensationGain compensation
Gain compensation
The first step of the data processing on raw IR data is always the gain compensation, regardless of pixel or subpage
number.
GO
\*wj
&
'
@AB
GOYF»IZI
!
\*wj
@AB
!
\*wj
@AB
º
If º¾ @AB
º
GO
\*wj
&
'
º!¼ º º¼ ººN
11.2.2.5.2.
11.2.2.5.2.11.2.2.5.2.
11.2.2.5.2. Offset calculation
Offset calculationOffset calculation
Offset calculation
GO
PQ
RST
&
'
VWWXYZ
*[SR*\S
<V==
R]^
38
!
P``
a0bc
1de
<V==
f]ghij
3t
!
P``
a0bc
adblmn
<oWWXYZ& '!
P``
a0bc
1cmn0n2
VWWXYZ
*[SR*\S
ÂÂ
If VWWXYZ
*[SR*\S
º
As the row=12, we select EEPROM cell 0x2414 (± OCC_rows_12…08 (4 x 4bit)) and extract the four most significant bits
corresponding to parameter OCC_rows_12. If another row number is selected, the corresponding OCC parameter must
be selected.
V==
R]^
38
KK
>p%qq
>p>>>
%
38
>p%%>p>>>
%
38
If V==
R]^
38
V==
rf*gS
1de
KK
>p%q>
>p>>>
%
s
>pq%>>p>>>
%
s
Please note that V==
rf*gS
1de
is a common parameter for all V==
R]^
_
calculation
As the column=16, we select EEPROM cell 0x2425 (± OCC_column_16…13 (4 x 4bit)) and extract the four most
significant bits corresponding to parameter OCC_columns_16. If another column number is selected, the
corresponding OCC parameter must be selected.
V==
f]ghij
3t
KK
>p%qJ
>p>>>
%
38
>pK>K>p>>>
%
38
If V==
f]ghij
3t
V==
rf*gS
adblmn
KK
>p%q>
>p>>>
%
u
>pq%>>p>>>
%
u
Please note that V==
rf*gS
adblmn
is a common parameter for all V==
f]ghij
k
calculation