LM96194CISQ/NOPB National Semiconductor, LM96194CISQ/NOPB Datasheet - Page 65

• Manufacturer Part Number: LM96194CISQ/NOPB
• Description: IC TRUTHERM HDWR MONITOR 48-LLP
• Manufacturer: National Semiconductor
• Series: PowerWise®, TruTherm®r

Specifications of LM96194CISQ/NOPB

• Function: Fan Control, Temp Monitor
• Topology: ADC (Sigma Delta), Comparator, Fan Control, Multiplexer, Register Bank
• Sensor Type: External & Internal
• Sensing Temperature: -40°C ~ 85°C, External Sensor
• Output Type: SMBus™
• Output Alarm: No
• Output Fan: Yes
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 48-LLP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: LM96194CISQTR

Register
Address
Register
Address
16.12 LIMIT REGISTERS
16.12.1 Registers 78–7Fh Temperature Limit Registers
If an external temperature input or the internal temperature sensor either exceeds the value set in the high limit register or falls
below the value set in the low limit register, the corresponding bit in the B_ and H_Error Status 1 register is set automatically by
the LM96194. For example, if the temperature read from the Remote1− and Remote1+ inputs exceeds the Processor (Zone1) High
Temp register limit setting, the ZN1_ERR bit in both B_Error Status 1 and H_Error Status 1 registers is set. The temperature limits
in these registers is represented as 8 bit, 2’s complement, signed numbers in Celsius.
If any high temp limit register is set to 80h then the B_ and H_Error Status register bit for that temperature channel is masked.
16.12.2 Registers 80–83h Fan Boost Temperature Registers
If any thermal zone exceeds the temperature set in the Fan Boost Limit register, both of the PWM outputs are set to 100%. The
fan boost function takes precedence over low-resolution manual override. High-resolution manual overide takes priority over the
fan boost function. This is a safety feature that attempts to cool the system if there is a potentially catastrophic thermal event. If
set to 7Fh and the fan control temperature resolution is 1°C, the feature is disabled.
Default = 60°C = 3Ch for zones 1 and 2
Default = 35°C = 23h for zones 3 and 4
The temperature has to fall the number of degrees specified in the Fan Boost Hysteresis registers, below this temperature to cause
the PWM outputs to return to normal operation. The fan boost function can be disabled by setting the associated register to 80h.
7Ah
7Bh
7Ch
7Dh
7Eh
7Fh
78h
79h
80h
81h
82h
83h
Read/
Write
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Read/
Write
R/W
R/W
R/W
R/W
External Digital (Zone4)
External Digital (Zone4)
Processor 1 (Zone1)
Processor 1 (Zone1)
Fan Boost Temp
Fan Boost Temp
Fan Boost Temp
Fan Boost Temp
MMBT3904 (Zone2)
MMBT3904 (Zone2)
Internal (Zone3)
Internal (Zone3)
Register
High Temp
High Temp
High Temp
High Temp
Zone 1
Zone 2
Zone 3
Zone 4
Low Temp
Low Temp
Low Temp
Low Temp
Name
Register
Name
Bit 7
7
7
7
7
Bit 7
7
7
7
7
7
7
7
7
Bit 6
6
6
6
6
65
Bit 6
6
6
6
6
6
6
6
6
Bit 5
5
5
5
5
Bit 5
5
5
5
5
5
5
5
5
Bit 4
4
4
4
4
Bit 4
4
4
4
4
4
4
4
4
Bit 3
3
3
3
3
Bit 3
3
3
3
3
3
3
3
3
Bit 2
2
2
2
2
Bit 2
2
2
2
2
2
2
2
2
Bit 1
Bit 1
1
1
1
1
1
1
1
1
1
1
1
1
Bit 0
Bit 0
0
0
0
0
0
0
0
0
0
0
0
0
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Default
Default
Value
Value
3Ch
3Ch
23h
23h
80h
80h
80h
80h
80h
80h
80h
80h