Datasheet

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MAX31826
1-Wire Digital Temperature Sensor
with 1Kb Lockable EEPROM
64-Bit ROM Code
Each device contains a unique 64-bit code stored in ROM
(Figure 3). The least significant 8 bits of the ROM code
contain the device’s 1-Wire family code, 3Bh. The next 48
bits contain a unique serial number. The most significant
8 bits contain a cyclic redundancy check (CRC) byte that
is calculated from the first 56 bits of the ROM code. See
the CRC Generation section for a detailed explanation
of the CRC bits. The 64-bit ROM code and associated
ROM function control logic allow the device to operate as
a 1-Wire device using the protocol detailed in the 1-Wire
Bus System section.
Figure 1. Supplying the Parasite-Powered MAX31826 During Temperature Conversions
Figure 2. Powering the MAX31826 with an External Supply
Figure 3. 64-Bit ROM Code
µP
V
PU
4.7kΩ
V
PU
1-Wire BUS
TO OTHER 1-Wire DEVICES
MAX31826
GND DQ V
DD
µP
V
PU
4.7kΩ
1-Wire BUS
TO OTHER 1-Wire DEVICES
(EXTERNAL SUPPLY)V
DD
MAX31826
GND DQ V
DD
MSb
8-BIT
CRC CODE
48-BIT SERIAL NUMBER
MSb MSbLSb
LSb
LSb
8-BIT FAMILY CODE
(3Bh)
MSbLSb