EVB90620 Datasheet, PDF (28/39 Pages) Melexis Microelectronic Systems – High precision non-contact temperature measurements

MLX90620
16x4 IR array
9.4 Communication to IR array
9.4.1 Read command
Opcode – 0x02.
The read command is used to read measurement, configuration and other data from the chip to the external
master.
The read command has the following parameters:
- Start address – 8bits. Address in the chip address space (0 to 255). It is the address of the first word
read.
- Address step – 8bits. On every read word the next address is formed by adding the address step to the
current address.
- Number of reads – 8bits. Number of the words to be read.
Different combinations are possible in order to read all, one line, one column, one exact pixel of the IR or Ta
sensors. They are summarized in the table below:
Sensors read
All IR
One line IR(i)
One column IR(j)
One pixel IR(i,j)
Start address
0x00
i
j*0x04
I + j*0x04
Address step
0x01
0x04
0x01
0x00
Table 17 RAM readout options
Number of reads
0x40
0x10
0x04
0x01
Slave address
S
T
A
R
T
0A
C
K
Start address
Address step
Number reads
Read Opcode
parameter
parameter
parameter
S
T
A
R
A
A
A
AT
C
C
C
C
K
K
K
K
Slave address
1A
C
K
Read Word0
LSByte
A
C
K
Read Word0
MSB yte
A
C
K
Read WordN
LS Byte
A
C
K
Read WordN
MS Byte
S
T
O
AP
C
K
Read N 16bit words
Figure 21: RAM readout command structure
3001090620
Rev 4.0
Page 28 of 40
Datasheet IR16x4
19 September 2012