MLX75031 Datasheet, PDF (21/67 Pages) Melexis Microelectronic Systems – Optical Gesture & Proximity Sensing IC

MLX75031
Optical Gesture & Proximity Sensing IC
with Integrated LED Drivers
Datasheet
• Shorting any channel to GNDA/GNDD/GNDAMB will make the readout of the whole ambient block
useless. At this time a maximum current of 14mA might be constantly pulled from the supply,
independent of the amount of channels that is shorted to GNDA/GNDD/GNDAMB.
• During normal operation, node GNDAMB should be considered a ground pin. Shorting this pin to
any other voltage might result in a shortcurrent of max 800mA!
• Because of such unwanted effects, a detection of an error in diagnostics mode should be followed
by a disabling of the ambient channels in order to avoid disturbing the operation of other blocks in
the system.
• Note that unused channels should be connected with an external resistance (~60kOhm) to
GNDAMB. Doing so will avoid disturbing the other channels, but will give a constant error on the
channel connected to GNDAMB.
8.3. Temperature Sensor
The on-chip temperature sensor measures the IC temperature. The output voltage of the sensor is
converted by the 16-bit ADC. The sensor will be trimmed for the best result during the production. This
trimming value is not applied to the temperature sensor internally, but is available to the customer through
two on-chip registers Calib1 and Calib2, see 0. The Calib1 register contains the slope of the temperature
curve in LSB/K. The Calib2 register contains the offset of the curve at a defined temperature at which the
chip is tested in production. An exemplary plot for the temperature sensor is given in
Figure 4 : Temperature sensor exemplary graph.
MLXM7L5X073513B0A8BtAemtepmepreartautureress[[ddeegg..CC]] vs. ADDCC oouuttoofftetmempepreartuarteursensseonrsor
(slope and offset depends on Calib1 and Calib2)
100
90
80
70
60
50
40
30
20
10
0
Calib1 Calib2
00
0 16
0 32
0 48
0 63
80
8 16
8 32
8 48
8 63
24 0
24 16
24 32
24 48
24 63
31 0
31 16
31 32
31 48
31 63
16 32
bold green Calib1 = 16 / Calib2 = 32:
-> no offset at 30 deg. C and
-> slope is -67 LSB/K
-10
-20
-30
-40
ADC output of temperature sensor [LSB]
Figure 4 : Temperature sensor exemplary graph
REVISION 001 – JANUARY, 2013
39010xxxxx
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