LM81BIMTX-3/NOPB National Semiconductor, LM81BIMTX-3/NOPB Datasheet - Page 12

• Manufacturer Part Number: LM81BIMTX-3/NOPB
• Description: IC MPU SYSTEM HDWR MON 24-TSSOP
• Manufacturer: National Semiconductor

Specifications of LM81BIMTX-3/NOPB

• Function: Hardware Monitor
• Topology: ADC (Sigma Delta), Comparator, Fan Speed Control, Register Bank
• Sensor Type: External & Internal
• Sensing Temperature: -40°C ~ 125°C, External Sensor
• Output Type: SMBus™
• Output Alarm: No
• Output Fan: No
• Voltage - Supply: 2.8 V ~ 3.8 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 24-TSSOP
• Monitored Voltage: 2.5 V , 3.3 V , 5 V , 12 V
• Manual Reset: Not Resettable
• Watchdog: Watchdog
• Battery Backup Switching: No
• Supply Voltage (max): 3.8 V
• Supply Voltage (min): 2.8 V
• Supply Current (typ): 400 uA (Typ)
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 40 C
• Power Fail Detection: No
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: LM81BIMTX-3

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Configuration Register
Interrupt Status Register 1
Interrupt Status Register 2
Interrupt Mask Register 1
Interrupt Mask Register 2
CI Clear Register
VID/Fan Divisor Register
Serial Bus Address Register
VID4 Register
Temperature Configuration
Register
Extended Mode Register 1
Extended Mode Register 2
Value RAM DAC Data
Register
Value RAM
Functional Description
2.1 Internal Registers of the LM81
Register
TABLE 1. The internal registers and their corresponding internal LM81 addresses are as follows:
LM81 Internal Hex
Address
20h-3Fh
(Continued)
4Ch
4Dh
40h
41h
42h
43h
44h
46h
47h
48h
49h
4Bh
19h
0101 XXXX
0010 11XX
0000 1000
0000 0000
0000 0000
0000 0000
0000 0000
0000 0000
1000 000X
0000 0001
0100 0100
0000 0000
1111 1111
Power on
Value
12
The upper four bits set the divisor for Fan Counters 1
and 2. The lower four bits reflect the state of the
VID0-VID3 inputs.
The lower 2 bits reflect the state of A1 and A0, the
Serial Bus address input pins.
The lower bit reflects the state of VID4 input.
Contains: monitoring results (temperature, voltages,
fan counts), WATCHDOG limits, and
Company/Stepping IDs
Notes