Datasheet
MLX90640 32x24 IR array
Datasheet
Page 40 of 60
REVISION 11 – 3 AUGUST 2018
11.2.2.5.4.
11.2.2.5.4.11.2.2.5.4.
11.2.2.5.4. IR data Emissivity compensation
IR data Emissivity compensationIR data Emissivity compensation
IR data Emissivity compensation
Emissivity compensation: For the example we assume Emissivity = 1. Note that the Emissivity coefficient is user
defined and it is not stored in the device EEPROM)
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11.2.2.6.
11.2.2.6.11.2.2.6.
11.2.2.6. CP data calculations
CP data calculationsCP data calculations
CP data calculations
11.2.2.6.1.
11.2.2.6.1.11.2.2.6.1.
11.2.2.6.1. Compensating the GAIN of CP pixel
Compensating the GAIN of CP pixelCompensating the GAIN of CP pixel
Compensating the GAIN of CP pixel
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NOTE: In order to limit the noise in the final To calculation it is advisable to filter the CP readings at this point of
calculation. A good practice would be to apply a Moving Average Filter with length of 16 or higher.
11.2.2.6.2.
11.2.2.6.2.11.2.2.6.2.
11.2.2.6.2. Compensating offset,
Compensating offset,Compensating offset,
Compensating offset,
Ta and VDD
Ta and VDDTa and VDD
Ta and VDD
of CP pixel
of CP pixelof CP pixel
of CP pixel
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The value of the offset for compensating pixel for the subpage 1 depends on the reading pattern. In case the chess
reading pattern mode is used following formula is to be applied:
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In case of interleaved mode is used following formula is to be applied:
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The correction parameter (highlighted in yellow) is extracted in Error! Reference source not found.
Where:
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