lm73cimkx-1 National Semiconductor Corporation, lm73cimkx-1 Datasheet - Page 10

• Manufacturer Part Number: lm73cimkx-1
• Description: 2.7v, Sot-23, 11-to-14 Bit Digital Temperature Sensor With 2-wire Interface
• Manufacturer: National Semiconductor Corporation

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1.0 Functional Description
FIGURE 2. ALERT Temperature Response cleared by
FIGURE 1. ALERT Temperature Response cleared
writing a "1" to the ALERT Reset Bit.
when temperature crosses T
LOW
(Continued)
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1.6 COMMUNICATING with the LM73
The data registers in the LM73 are selected by the Pointer
Register. At power-up the Pointer Register is set to “00h”, the
location for the Temperature Register. The Pointer Register
latches the last location it was set to. Note that all Pointer
Register bits are decoded; any incorrect pointer values will
not be acknowledged and will not be stored in the Pointer
Register (Note 13).
A Write to the LM73 will always include the address byte and
the pointer byte.
A Read from the LM73 can take place either of two ways:
1. If the location latched in the Pointer Register is correct
2. If the Pointer Register needs to be set, then an address
The data byte is read out of the LM73 by the most significant
bit first. At the end of a read, the LM73 can accept either an
Acknowledge or No Acknowledge bit from the Master. No
Acknowledge is typically used as a signal to the slave that
the Master has read its last byte.
(that is, the Pointer Register is pre-set prior to the read),
then the read can simply consist of an address byte,
followed by retrieving the data byte. Most of the time it is
expected that the Pointer Register will point to Tempera-
ture Registers because that will be the data most fre-
quently read from the LM73.
byte, pointer byte, repeat start, and another address
byte will accomplish a read.