EVB90129 Datasheet, PDF (5/13 Pages) Melexis Microelectronic Systems – Asset management and monitoring (security and integrity)

EVB90129
MLX90129 Evaluation Board
2 EVB90129 Power Supplies
The EVB90129 allows supplying the MLX90129 through three
ways. Power supply can be provided by a battery CR2032, by
an external power supply input or a by an electromagnetic
field from a RFID reader. The jumper CON2/ VDD_Selector
allow selecting the regulated source of power. This source is
filtered by L1 and C5. C3 is not mounted. The energy from an
applied electromagnetic field is collected with the 13.56MHz
tuned antenna through the pin COIL1 and COIL2. A Zener
diode on the VFIELD pin ensures the compliance with the
maximum electrical rating defined in the MLX90129
datasheet. Indeed, very powerful reader could provide
enough energy to exceed this rating. The 100 nF capacitor
C2 on VFIELD pin allows storing of this energy in order to
supply the MLX90129 and the external sensor in sensor tag
application.
CON2
3
2
1
VDD_SPI
VDD_BAT
VDD_Selector
L1
VBAT_29
Z600
C5
100n
GND
VFIELD_29
C2
100n
D1
BZV55/C4V7
GND
The following drawings show how to set jumpers in order to select the power supply source
External power supply
Battery powered
Electromagnetic field powered
Depending on the mode used, care should be taken about the internal MLX90129 switches for power
management. Please read the datasheet for more information on this topic.
3 EVB90129 Communication
The EVB90129 allows communication with the MLX90129 through SPI and RFID and also between the
MLX90129 and an external memory during a data logging application. The SPI signals are received through
the SPI connector and the SS_Selector allows selecting the communication channel. RFID signals are
received through the RFID antenna connected to the MLX90129.
3.1 External SPI connector
The digital Inputs/Outputs of the SPI bus and the IRQ
pin of the MLX90129 are available on the connector
CON1/CON_SPI. In addition the external SPI connector
provides pins to supply EVB90129 (VDD_SPI and
GND), and a connection to the Voltage Regulated
output VREG. The following table, schematic and
diagram give information about the SPI connector. Per
default, the resistor R14 is not mounted.
IRQ_29
VDD_SPI
MOSI
GND
CON1
12
34
56
78
CON_SPI
SS_MCU
MISO
SCK
R14 VREG
0R
390129012901
Rev 003
Page 5 of 13
Evaluation Board
June-2010