LM41CIMTX/NOPB National Semiconductor, LM41CIMTX/NOPB Datasheet - Page 20

• Manufacturer Part Number: LM41CIMTX/NOPB
• Description: IC HARDWARE MONITOR 14-TSSOP
• Manufacturer: National Semiconductor

Specifications of LM41CIMTX/NOPB

• Applications: Monitors
• Interface: 1-Wire
• Voltage - Supply: 3 V ~ 3.6 V
• Package / Case: 14-TSSOP
• Mounting Type: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: LM41CIMTX

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001 001
2.0 Register Set
2.9.3 Temperature Data Readout (Addr: 001 001; 09h)
All LM41 temperature data has a common format. The LM41’s temperature data format is two’s complement and has 10-bits of
resolution with the LSb having a weight of 0.5 ˚C. The LM41 can resolve temperature between +255.5 ˚C and -256 ˚C, inclusive.
It can measure local temperatures between +85 ˚C and 0 ˚C and remote temperatures between +125 ˚C and 0 ˚C with an
accuracy of
Add
Reg
15-6
5-3
Bit
0
1
2
Sensor Number
Register
Name
Local
Temperature
Data
Readout
Processor/
Remote
Temperature
Data
Readout
(SNUM)
Type
RO
RO
RO
RO
RO
0
1
±
3.0 ˚C.
Reserved. Will always read "0".
Reserved for Local Temperature Data Readout. Will always read "0".
EF (Error Flag) for Remote Temperature Data Readout. This bit indicates that an error was detected
during the measurement of the current remote Temperature sensor such as a diode fault condition. When a
diode fault occurs the value of the temperature reading will be 200h or -256˚C.
0: No error detected.
1: Error detected.
SNUM (Sensor Number). This field indicates the number of the current Temperature Sensor, to which the
data in the Temperature Readout field belongs. Temperature Sensor 0 is always assigned to the local
sensor of the LM41.
0: Local temperature sensor (see Table Thermal Diode Input Mapping)
1: Remote sensor (see Table Thermal Diode Input Mapping)
Reserved. Will always read "0".
Temperature Readout. This field holds the result of the temperature measurement. The active size of this
field for the LM41 is 10-bits, left justified. See Table Temperature Data Format for examples.
Temperature
+140 ˚C
+100 ˚C
- 0.5 ˚C
- 40 ˚C
+1 ˚C
-1 ˚C
0 ˚C
R/
W
R
Val
(Continued)
O
R
P
MSb
MSb
Sign
Bit
15
128
Bit
14
˚C
Processor, D+/D-
64˚C 32˚C 16˚C 8˚C 4˚C 2˚C 1˚C
Thermal Diode Input Mapping
Bit
13
Sensor Input
Temperature Data Format
Local
Bit
12
Bit
11
01 0001 1000
00 1100 1000
00 0000 0010
00 0000 0000
11 1011 0000
20
11 1111 1111
11 1111 1110
Description
Bit
Binary
10
Bit
9
Bit
8
Bit
7
Board Connection
none
CPU Thermal Diode, MMBT3904
Thermal Diode or GPU Thermal Diode
0.5
Bit
˚C
6
Bit
5
0
0
Reserved
Reserved
Bit
4
0
0
0C8h
3FFh
3FEh
3B0h
002h
000h
118h
Bit
Hex
3
0
0
NUM
Bit
S
2
Reserved
Bit
EF
1
0
LSb
Res
Bit
0
0
0