emc1403 Standard Microsystems Corp., emc1403 Datasheet - Page 37

• Manufacturer Part Number: emc1403
• Description: 1 Degree C Temperature Sensor With Beta Compensation
• Manufacturer: Standard Microsystems Corp.

1°C Temperature Sensor with Beta Compensation
Datasheet
SMSC EMC1403/EMC1404
6.13
ADDR.
25h
26h
2
0
0
0
1
R/W
R/W
R/W
value to set the respective counters. The consecutive THERM counter is incremented whenever any
measurement exceed the corresponding THERM Limit.
If the temperature drops below the THERM limit, then the counter is reset. If a number of consecutive
measurements above the THERM limit occurs, then the THERM pin is asserted low.
Once the THERM pin has been asserted, the consecutive therm counter will not reset until the
corresponding temperature drops below the THERM Limit minus the THERM Hysteresis value.
The bits are decoded as shown in
conversions.
Bits 3-1 - CALRT[2:0] - Determine the number of consecutive measurements that must have an out of
limit condition or diode fault before the ALERT pin is asserted. All temperature channels use this value
to set the respective counters. The bits are decoded as shown in
consecutive out of limit conversion.
This register is used to set the Beta Compensation factor that is used for the external diode channels.
Bit 3 - ENABLEx - Enables the Beta Compensation factor autodetection function. This function shall
be disabled for External Diode 2.
Bit 2-0 - BETAx[2:0] - These bits always reflect the current beta configuration settings. If autodetection
circuitry is enabled, then these bits will be updated automatically and writing to these bits will have no
effect. If the autodetection circuitry is disabled, then these bits will determine the beta configuration
setting that is used for their respective channels.
Beta Configuration Registers
‘0’ - The Beta Compensation Factor autodetection circuitry is disabled. The External Diode will
always use the Beta Compensation factor set by the BETAx[2:0] bits.
‘1’ (default) - The Beta Compensation factor autodetection circuitry is enabled. At the beginning of
every conversion, the optimal Beta Compensation factor setting will be determined and applied.
The BETAx[2:0] bits will be automatically updated to indicate the current setting.
Diode 1 Beta
Configuration
Diode 2 Beta
Configuration
REGISTER
External
External
1
0
0
1
1
Table 6.14 Consecutive Alert / THERM Settings
Table 6.15 Beta Configuration Registers
B7
-
-
0
0
1
1
1
B6
-
-
DATASHEET
Table
B5
-
-
37
6.14. The default setting is 4 consecutive out of limit
NUMBER OF CONSECUTIVE OUT OF LIMIT
B4
-
-
ENABLE1
ENABLE2
(default for CTHRM[2:0])
(default for CALRT[2:0])
B3
MEASUREMENTS
Table
1
2
3
4
B2
BETA1[2:0]
BETA2[2:0]
6.14. The default setting is 1
B1
Revision 1.30 (05-06-08)
B0
EMC1403
or 07h for
EMC1404
DEFAULT
08h for
08h