EMC1424 SMSC Corporation, EMC1424 Datasheet - Page 36

• Manufacturer Part Number: EMC1424
• Description: (EMC1423 / EMC1424) Temperature Sensor
• Manufacturer: SMSC Corporation

Revision 1.16 (03-15-07)
6.11
ADDR.
1Eh
Hardware Thermal Shutdown Limit Register
R/W
R
The Software Thermal Shutdown Configuration Register controls whether any of the software channels
will assert the SYS_SHDN pin. If a channel is enabled, the temperature is compared against the
corresponding THERM Limit. If the measured temperature exceeds the THERM Limit, then the
SYS_SHDN pin is asserted. This functionality is in addition to the Hardware Shutdown circuitry.
Bit 3 - E3SYS - configures the External Diode 3 channel to assert the SYS_SHDN pin based on it’s
respective THERM Limit.
Bit 2 - E2SYS - configures the External Diode 2 channel to assert the SYS_SHDN pin based on it’s
respective THERM Limit.
Bit 1 - E1SYS - configures the External Diode 1 channel to assert the SYS_SHDN pin based on the
THERM Limit.
Bit 0 - INTSYS - configures the Internal Diode channel to assert the SYS_SHDN pin based on it’s
respective THERM Limit.
This read only register returns the Hardware Thermal Shutdown Limit selected by the value of the pull-
up resistors on the ALERT and SYS_SHDN pins. The data represents the hardware set temperature
in °C using the active temperature setting set by the RANGE bit in the Configuration Register. See
Table 5.4
When the External Diode 1 Temperature exceeds this limit, the SYS_SHDN pin is asserted and will
remain asserted until the External Diode 1 Temperature drops below this limit minus 10°C.
‘0’ (default) - the External Diode 3 channel is not linked to the SYS_SHDN pin. If the temperature
exceeds it’s THERM Limit, the E3THERM status bit is set but the SYS_SHDN pin is not asserted.
‘1’ - the External Diode 3 channel is linked to the SYS_SHDN pin. If the temperature exceeds it’s
THERM Limit, the E3THERM status bit is set and the SYS_SHDN pin is asserted. It will remain
asserted until the temperature drops below it’s THERM Limit minus the THERM Hysteresis.
‘0’ (default) - the External Diode 2 channel is not linked to the SYS_SHDN pin. If the temperature
exceeds it’s THERM Limit, the E2THERM status bit is set but the SYS_SHDN pin is not asserted.
‘1’ - the External Diode 2 channel is linked to the SYS_SHDN pin. If the temperature exceeds it’s
THERM Limit, the E2THERM status bit is set and the SYS_SHDN pin is asserted. It will remain
asserted until the temperature drops below it’s THERM Limit minus the THERM Hysteresis.
‘0’ (default) - the External Diode 1 channel is not linked to the SYS_SHDN pin. If the temperature
exceeds the THERM Limit, the E1THERM status bit is set but the SYS_SHDN pin is not asserted.
‘1’ - the External Diode 1 channel is linked to the SYS_SHDN pin. If the temperature exceeds the
THERM Limit, the E1THERM status bit is set and the SYS_SHDN pin is asserted. It will remain
asserted until the temperature drops below the THERM Limit minus the THERM Hysteresis.
‘0’ (default) - the Internal Diode channel is not linked to the SYS_SHDN pin. If the temperature
exceeds it’s THERM Limit, the ITHERM status bit is set but the SYS_SHDN pin is not asserted.
‘1’ - the Internal Diode channel is linked to the SYS_SHDN pin. If the temperature exceeds it’s
THERM Limit, the ITHERM status bit is set and the SYS_SHDN pin is asserted. It will remain
asserted until the temperature drops below it’s THERM Limit minus the THERM Hysteresis.
Hardware Thermal
Shutdown Limit
for the data format.
REGISTER
Table 6.12 Hardware Thermal Shutdown Limit Register
128
B7
DATASHEET
B6
64
36
B5
32
1°C Temperature Sensor with Hardware Thermal Shutdown
B4
16
B3
8
B2
4
B1
2
SMSC EMC1423/EMC1424
B0
1
DEFAULT
Datasheet
N/A