MLX75031 Datasheet, PDF (16/67 Pages) Melexis Microelectronic Systems – Optical Gesture & Proximity Sensing IC

MLX75031
Optical Gesture & Proximity Sensing IC
with Integrated LED Drivers
Datasheet
8.1.2. Active Light Channel DC Light Measurement
The DC current compensation circuitry of the transimpedance amplifier is able to supply and measure the
DC current supplied to the photodetector. Both Active Light channels are identical in structure.
In order to reach a feasible resolution in the current range of interest (low currents in the range up to
900uA), the measurement characteristics will saturate for currents above the IDC current range, however
the compensation circuit is nevertheless able to supply the specified current levels to the detector (up to
900uA). The given ADC word length for the Active Light channel DC light data is 16bit.
The typical transfer function of DC measurement is defined by formula:
I _{pd _ DC}
=
ADC
_
DC
35
− 1760
I_{pd_DC} : The DC current through photo diode (in uA).
ADC_DC : the decimal value of the DC measurement (see Output Data Frame of read-out).
REVISION 001 – JANUARY, 2013
39010xxxxx
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