Rainbow Electronics LM95010 - Manual (Page 16)

2.0 Register Set
(Continued)
Bit Type Description
2-0 R Resolution. This field defines the value of 1 LSb of the Temperature Readout field in the Readout Register.
The SensorPath specification defines many different weights for the temperature LSb. The LM95010
supports a resolution of 0.25 ˚C and thus a value of 010 for this field. For a full definition of this field please
refer to the SensorPath specification.
5-3 R Number of Bits. This field defines the total number of significant bits of the Temperature Readout field in the
Readout register. The total number of osignificant bits includes the number of bits representing the interger
part of the temperature data and the fractional part of it, as defined by the Resolution field. The LM95010
supports 10 bits and thus a value of 001 for this field. For a full definition of this field please refer to the
SensorPath specification.
6 R Sign (Signed Data). Defines the type of data in the Temperature Readout field of the Readout register.
0: Unsigned, positive fixed point value.
1: Signed, 2’s complement fixed point value. (value for the LM95010)
7 R RoutSize (Readout Register size). Defines the total size of the Readout register.
0: 16 bits. (LM95010 default)
1: 24 bits.
8 R/W IntSens (Internal Sensor Support). Indicates if the device supports internal temperature measurements, as
the LM95010 does.
0: No internal temperature measurement
1: Internal temperature sensor implemented. (value for the LM95010)
15-9 RO Reserved. Will always read "0".
2.9.3 Temperature Data Readout (Addr 11o)
Reg
Add
Register
Name
R/
W
P
O
R
Val
Bit
15
MSb
Bit
14
Bit
13
Bit
12
Bit
11
Bit
10
Bit
9
Bit
8
Bit
7
Bit
6
Bit
5
Bit
4
Bit
3
Bit
2
Bit
1
Bit
0
LSb
001 001
Temperature
Data
Readout
R
MSb
Sign
64˚C 32˚C 16˚C 8˚C 4˚C 2˚C 1˚C
0.5
˚C
LSb
0.25
˚C
Reserved
0 0 0 0 0 0
The LM95010’s temperature data format is two’s complement and has 10-bits of resolution with the LSb having a weight of
0.25 ˚C. The LM95010 can resolve temperature between +127.75 ˚C and -128 ˚C, inclusive. It can measure temperatures
between +127.75 ˚C and −20 ˚C with an accuracy of
± 3.0 ˚C.
Temperature Data Format
Decimal Binary Hex
+127.75 ˚C 01 1111 1111 1FFh
+100.00 ˚C 01 1001 0000 190h
+1.00 ˚C 00 0000 0100 004h
+0.25 ˚C 00 0000 0001 001h
0 ˚C 00 0000 0000 000h
-0.25 ˚C 11 1111 1111 3FFh
-1.00 ˚C 11 1111 1100 3FCh
-20.00 ˚C 11 1011 0000 3 B0h
-39.75 ˚C 11 0110 0001 361h
-40.00 ˚C 11 0110 0000 360h
-128.00 ˚C 10 0000 0000 200h
LM95010
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