1°C Temperature Sensor with Hardware Thermal Shutdown
Datasheet
Table 6.1 Register Set in Hexadecimal Order (continued)
REGISTER
ADDRESS
DEFAULT
VALUE
R/W
REGISTER NAME
FUNCTION
PAGE
40h
FDh
FEh
FFh
R/W
Filter Control
Controls the digital filter setting for
the External Diode channel
00h
Table 6.21
5Dh
Page 34
R
R
R
Product ID
SMSC ID
Revision
Stores a fixed value that identifies
each product
Page 35
Page 35
Page 35
Stores a fixed value that
represents SMSC
Stores a fixed value that
represents the revision number
01h
6.1
Data Read Interlock
When any temperature channel high byte register is read, the corresponding low byte is copied into
an internal ‘shadow’ register. The user is free to read the low byte at any time and be guaranteed that
it will correspond to the previously read high byte. Regardless if the low byte is read or not, reading
from the same high byte register again will automatically refresh this stored low byte data.
6.2
Temperature Data Registers
Table 6.2 Temperature Data Registers
ADDR
R/W
REGISTER
B7
B6
B5
B4
B3
B2
B1
B0
DEFAULT
00h
29h
01h
10h
R
Internal Diode
High Byte
128
64
32
16
8
4
2
1
00h
R
R
R
Internal Diode
Low Byte
0.5
128
0.5
0.25
64
0.125
32
-
16
-
-
8
-
-
4
-
-
2
-
-
1
-
00h
00h
00h
External Diode
High Byte
External Diode
Low Byte
0.25
0.125
As shown in Table 6.2, all temperatures are stored as an 11-bit value with the high byte representing
the integer value and the low byte representing the fractional value left justified to occupy the MSBits.
6.3
Status Register
Table 6.3 Status Register
ADDR
R/W
REGISTER
B7
B6
B5
B4
B3
B2
B1
B0
DEFAULT
02h
R
Status
BUSY
-
-
HIGH
LOW
FAULT
THERM
HWSD
00h
The Status Register reports general error conditions. To identify specific channels, refer to Section 6.9,
Section 6.14, Section 6.15, and Section 6.16. The individual Status Register bits are cleared when the
appropriate High Limit, Low Limit, or THERM Limit register has been read or cleared.
Revision 1.24 (02-05-08)
SMSC EMC1422
DATA2S6HEET
SMSC [ SMSC CORPORATION ]
