SI7013 Datasheet, PDF (30/43 Pages) Silicon Laboratories – I2C HUMIDITY AND TWO-ZONE TEMPERATURE SENSOR

Si7013
5.7. Electronic Serial Number
The Si7013 provides a serial number individualized for each device that can be read via the I²C serial interface.
Two I²C commands are required to access the device memory and retrieve the complete serial number. The
command sequence, and format of the serial number response is described in the figure below:
First access:
Master
Slave
S
S
2nd access:
S
S
Slave Address W
Slave Address R
SNA_3
ACK
SNA_1
ACK
Slave Address W
Slave Address R
SNB_3
ACK
SNB_1
ACK
ACK
ACK
CRC
CRC
ACK
ACK
SNB_2
SNB_0
0x3A
ACK
ACK
0x3C
ACK
ACK
ACK 0X0F
SNA_2 ACK
SNA_0 ACK
ACK 0X09
CRC
ACK
CRC NACK
ACK
CRC ACK
CRC NACK P
ACK
P
The format of the complete serial number is 64-bits in length, divided into 8 data bytes. The complete serial number
sequence is shown below:
SNA_3
SNA_2
SNA_1
SNA_0
SNB_3
SNB_2
SNB_1
SNB_0
The SNB3 field contains the device identification to distinguish between the different Silicon Labs relative humidity
and temperature devices. The value of this field maps to the following devices according to this table:
0x00 or 0xFF engineering samples
0x0D=13=Si7013
0x14=20=Si7020
0x15=21=Si7021
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Rev. 0.95