1°C Triple SMBus Sensor with Resistance Error Correction
Datasheet
The limits are automatically compared to the temperature measurement results (TM) and have been
exceeded if (TM ≤ TL or TM > TH). If either limit is exceeded then the appropriate bit is set high in the
status register and the ALERT/THERM2 output will respond as described in Section 4.5 on page 12.
The THERM limit (TTH) is a single byte value set by the THERM Limit register. Exceeding the THERM
limit asserts the ADDR/THERM signal as described in Section 4.6 on page 12. When the
ALERT/THERM2 pin is configured as THERM2, then exceeding the high limit asserts this pin.
4.14
4.15
THERM Hysteresis Register
The THERM hysteresis register holds a hysteresis value that impacts the de-assertion of THERM as
shown in Figure 4.5 on page 13. It defaults to 10°C and can be set by the user at any time after power
up. When the ALERT/THERM2 pin is configured as THERM2, then the output will not de-assert until the
temperature drops below the Temperature High Limit minus the THERM Hysteresis value.
Diode Fault Register
The Diode Fault register holds the status of any diode faults that may have occurred as shown in
Table 4.8.
Table 4.8 Diode Fault Register
DIODE FAULT REGISTER
BIT
NAME
FUNCTION
DEFAULT
1
EXFLT1
1 = Remote 1 is open circuit
0 = no fault
0
0
EXFLT2
1 = Remote 2 is open circuit
0 = no fault
0
4.16
One-Shot Register
Writing to the one-shot register while in standby mode initiates a conversion and comparison cycle.
The EMC1033 will execute a temperature measurement, compare the data to the limit registers and
return to the standby mode. A write to the one-shot register will be ignored if it occurs while the
EMC1033 is in run mode.
4.17
Scratchpad Registers
The scratchpad registers may be used to verify communication via the SMBus. These registers do not
have any affect on the operation of the device.
Revision 1.1 (01-19-07)
SMSC EMC1033
DATA1S8HEET
SMSC [ SMSC CORPORATION ]
