EVB90129 Datasheet, PDF (8/13 Pages) Melexis Microelectronic Systems – Asset management and monitoring (security and integrity)

EVB90129
MLX90129 Evaluation Board
4 Sensor description
EVB90129 is delivered with three external sensors in addition to the internal temperature sensor of the
MLX90129; a light sensor, an external temperature sensor and a potentiometer. For each sensor, the
schematic and a configuration of the MLX90129 register is provided. The sensors are provided as examples
and have not been calibrated. The configuration provided is basic, there is no amplification (per default
gain=8), no threshold, and no offset with the DAC. The ADC mode is “11”, the initialization time is minimal and
there is no averaging so the chopper is disabled. The datalogging control bits (b4, b5, b6) of the “Control word”
are set. The MLX90129 datasheet provides more details about the register configuration.
The basic following configuration for sensor conditioning can be used for all sensors.
Content
# Hexa 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Sensor power
12 00FF 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1
Sensor trimming
14 0TT0 0 0 0 0 0 0 T T T T 0 0 0 0 0 0
‘T’ means Melexis trimming bits. Do not change.
4.1 Internal temperature sensor
The specifications of the internal temperature sensor are available in the MLX90129 datasheet. The following
register configuration allows monitoring the full range of the internal temperature sensor.
Content
Control word
Low threshold
High threshold
Conditioner config.
Connection config.
Resistance network
# Hexa 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
15 C070 1 1 0 0 0 0 0 0 0 1 1 1 0 0 0 0
16 0000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
17 0000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
18 0000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
19 0231 0 0 0 0 0 0 1 0 0 0 1 1 0 0 0 1
1A 8000 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
4.2 Light sensor
The light sensor is a phototransistor for ambient light sensor
measurement. To use, it, all the jumpers of the CON6/
LIGHT_SELECTOR have to be set in order to connect MLX90129
pins SENSSUP2, SENS1 and SENS2 to the sensor.
SENS2
SENS1
SENSSUP2
CON6
65
43
21
LIGHT_SELECTOR
Q1
TEPT5700
The schematic shows the sensor implementation and the following
R6
register configuration allows monitoring the ambient light on the
100R
phototransistor through the MLX90129.
This sensor fits mainly for the sun light monitoring. The output voltage
R7
with flashlight is very low.
0R
Content
Control word
Low threshold
High threshold
Conditioner config.
Connection config.
Resistance network
GND
# Hexa 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
15 C070 1 1 0 0 0 0 0 0 0 1 1 1 0 0 0 0
16 0000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
17 0000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
18 0000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
19 0000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
1A 0002 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0
390129012901
Rev 003
Page 8 of 13
Evaluation Board
June-2010