1°C Triple SMBus Sensor with Resistance Error Correction
Datasheet
is a function of temperature. The higher the temperature measured, the greater the error introduced.
To provide maximum flexibility to the user, the EMC1033 provides a 6-bit ideality factor register for
each remote diode. The ideality factor of the remote diode is programmed in these registers to
eliminate errors across all temperatures. See section Section 4.18, "Ideality Factor Register," on
page 19 for details on programming these registers.
4.4
Temperature Measurement Results and Data
The 11-bit temperature measurement results are stored in temperature value registers. The EMC1033
has two temperature ranges and the default range is from 0 to 127°C. This range uses binary number
format, and the most significant bit is not used. The extended range is from –64°C to +191°C and is
binary offset by 64°C. Table 4.1 shows the two temperature data formats with an LSB equivalent to
0.125°C. The format is selected as described in Section 4.11, "Configuration Register," on page 16
Table 4.1 Temperature Data Format
ACTUAL TEMP.
DEFAULT RANGE
BINARY
EXTENDED RANGE
OFFSET BINARY
(°C)
-63
0000 0000 000 Note 4.1
0000 0001 000 Note 4.2
-0.125
0
0000 0000 000 Note 4.1
0000 0000 000 Note 4.1
0000 0000 001
0011 1111 111
0100 0000 000
0100 0000 001
0100 0000 010
+0.125
+0.250
0000 0000 010
+1
0000 0001 000
0100 0001 000
+127
+128
0111 1111 000 Note 4.3
0111 1111 000 Note 4.3
1011 1110 000
1011 1111 000
+190
+191
0111 1111 000 Note 4.3
0111 1111 000 Note 4.3
1111 1110 000
1111 1111 000 Note 4.4
Note 4.1 Data in Binary Format reads 0000 0000 000 for all temperatures ≤ 0.00°C
Note 4.2 Data in Offset Binary Format reads 0000 0000 000 for all temperatures ≤ -64°C
Note 4.3 Data in Binary Format reads 0111 1111 000 for all temperatures ≥ +127°C
Note 4.4 Data in Offset Binary Format reads 1111 1111 000 for all temperatures ≥ +191°C
The 11-bit temperature data is stored with the 8 most significant bits stored in the High Byte register
and the 3 least significant bits in the Low Byte register. The Low Byte register contains the three least
significant bits as outlined in Table 4.2. These bits are stored in the upper three bits of the register,
and the five LSB positions of this register always read zero. In Table 4.2, the upper case “B” shows
the bit position of a 16-bit word created by concatenating the High Byte and Low Byte, and the lower
case “b” shows the bit position in the 11-bit temperature data. The resolution of the internal temperature
is 0.5°C and the b1 and b0 bits of the Internal Temperature Value Low Byte register will always read 0.
Table 4.2 Bit Position of Two Byte Values
HIGH BYTE
B15 B14 B13 B12 B11
b10 b9 b8 b7 b6
LOW BYTE
B10 B9
b5 b4
B8
b3
B7
b2
B6
b1
B5
b0
B4
B3
0
B2
0
B1
0
B0
0
0
SMSC EMC1033
11
Revision 1.1 (01-19-07)
DATASHEET
SMSC [ SMSC CORPORATION ]
