lm95172q National Semiconductor Corporation, lm95172q Datasheet - Page 15

• Manufacturer Part Number: lm95172q
• Description: Digital Temperature Sensor In Die Form With ?1?c Accuracy From 130?c To 160?c
• Manufacturer: National Semiconductor Corporation

1.7 INTERNAL REGISTER STRUCTURE
The LM95172Q has four registers that are accessible by is-
suing a command byte (a R/W Bit plus the register address:
Control/Status, T
these registers will be read or written is determined by the
Command Byte. See Section 1.4, "Communicating with the
LM95172Q", for a complete description of the serial commu-
nication protocol. The following diagram describes the Com-
mand Byte and lists the addresses of the various registers.
The temperature is read by lowering the CS line and then
1.7.1 Command Byte
Bit <7> Read/Write Bit. Tells the LM95172Q if the host will be writing to, or reading from, the register to which this byte is pointing.
Bits <6:3> Not Used. These Bits must be zero. If an illegal address is written, the LM95172Q will return 0000h on the subsequent
read.
Bits <2:0> Pointer Address Bits. Points to desired register. See table below.
Power-On Reset state: 00h
Reset Conditions: Upon Power-on Reset
HIGH
, T
LOW
, and Identification. Which of
R/W
P7
P2
0
0
0
0
1
1
1
1
P6
0
P5
P1
0
0
0
1
1
0
0
1
1
P4
0
P0
0
1
0
1
0
1
0
1
15
P3
0
clocking the data out from the 16-Bit temperature register; all
other registers are accessed by writing a Command Byte after
reading the temperature.
All registers can be communicated with, either in Continuous
Conversion mode or in Shutdown mode. When the
LM95172Q has been placed in Shutdown Mode, the Tem-
perature register will contain the temperature data which
resulted from the last temperature conversion (whether it was
the result of a continuous-conversion reading or a one-shot
reading).
Invalid. (Note 3)
Invalid. (Note 3)
Control/Status
Identification
Register
P2
T
T
Register Select
HIGH
LOW
P1
P0
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