DS1848
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Memory Location Name of Location Function of Location
00h to 47h
(the Table Select
Byte, E0h, must be
set to 01h or 02h to
access the Look-
Up Tables)
00h to 7Fh
(the Table Select
Byte, E0h, must be
set to 00h to access
the User EEPROM
Memory)
User Defined Look-Up Table
(LUT)
User Memory
This block contains the user-defined temperature
settings of the resistors. Values between 00h and
FFh can be written to either table to set the 256
position variable resistors. The first address
location, 00h, is used to set the resistor at -40°C.
Each successive memory location will contain the
resistor setting for the previous temperature +2°C.
For example, memory address 01h is the address
that will set the resistor in a -38°C environment.
For default memory settings and programming
the look-up table, refer to the Programming the
Look-Up Table (LUT) section of the datasheet.
This block is for general-purpose user memory.
When shipped from the factory, memory
locations 60h – 6Bh contain the same information
as found in Look-Up Table 1, memory locations
28h – 33h. Memory locations 6Ch – 77h contain
the same information as found in Look-Up Table
2, memory locations 28h – 33h.
E0h Table Select Byte Writing to this byte determines if one of the two
72x8 EEPROM look-up tables or the user
EEPROM memory is selected for reading or
writing.
00h (User EEPROM selected)
01h (Look-Up Table 1 selected)
02h (Look-Up Table 2 selected)
E1h Configuration Byte
TAU – Temperature/Address Update
TEN – Temperature Update Enable
AEN – Address Update Enable
Default setting is 03h, TAU = 1, TEN = 1 and
AEN = 1.
TAU becomes a 1 after a temperature and address
update has occurred as a result of a temperature
conversion. The user can write this bit to 0 and
check for a transition from 0 to 1 in order to
verify that a conversion has occurred.
If TEN = 0, the temperature conversion feature is
disabled. The user sets the resistor in “manual
mode” by writing to addresses F0h and F1h to
control resistors 0 and 1, respectively.
TAU TEN AEN
