lm75adp NXP Semiconductors, lm75adp Datasheet - Page 6

• Manufacturer Part Number: lm75adp
• Description: Digital Temperature Sensor And Thermal Watchdog
• Manufacturer: NXP Semiconductors

NXP Semiconductors
LM75A_4
Product data sheet
7.4.1 Pointer register
7.4 Register list
8 devices can be connected to the same bus without address conflict. Because the input
pins, SCL, SDA and A2 to A0, are not internally biased, it is important that they should not
be left floating in any application.
Table 4.
1 = HIGH; 0 = LOW.
The LM75A contains four data registers beside the pointer register as listed in
The pointer value, read/write capability and default content at power-up of the registers
are also shown in
Table 5.
The Pointer register contains an 8-bit data byte, of which the two LSB bits represent the
pointer value of the other four registers, and the other 6 MSB bits are equal to 0, as shown
in
select the data register for write/read operation by including the pointer data byte in the
bus command.
Table 6.
Table 7.
Because the Pointer value is latched into the Pointer register when the bus command
(which includes the pointer byte) is executed, a read from the LM75A may or may not
include the pointer byte in the statement. To read again a register that has been recently
read and the pointer has been preset, the pointer byte does not have to be included. To
MSB
1
Register
name
Conf
Temp
Tos
Thyst
B7
0
B1
0
0
1
1
Table 6
and
Pointer
value
01h
00h
03h
02h
Address table
Register table
Pointer register
Pointer value
B6
0
B0
0
1
0
1
0
Table
Table
R/W
R/W
read only
R/W
R/W
7. The Pointer register is not accessible to the user, but is used to
B5
0
Selected register
Temperature register (Temp)
Configuration register (Conf)
Hysteresis register (Thyst)
Overtemperature shutdown register (Tos)
Rev. 04 — 10 July 2007
5.
0
POR
state
00h
n/a
5000h
4B00h
B4
0
Digital temperature sensor and thermal watchdog
1
Description
Configuration register: contains a single 8-bit data
byte; to set the device operating condition; default = 0.
Temperature register: contains two 8-bit data bytes;
to store the measured Temp data.
Overtemperature shutdown threshold register:
contains two 8-bit data bytes; to store the
overtemperature shutdown T
Hysteresis register: contains two 8-bit data bytes;
to store the hysteresis T
B3
0
A2
B2
0
hyst
A1
limit; default = 75 C.
os
B[1:0]
pointer value
limit; default = 80 C.
© NXP B.V. 2007. All rights reserved.
LM75A
LSB
A0
Table
6 of 24
5.