LM81CIMT-3/NOPB National Semiconductor, LM81CIMT-3/NOPB Datasheet - Page 11

• Manufacturer Part Number: LM81CIMT-3/NOPB
• Description: IC MONITOR SYS HARDWAR 24-TSSOP
• Manufacturer: National Semiconductor

Specifications of LM81CIMT-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
• Supply Voltage Range: 2.8V To 3.8V
• Reset Type: Active-Low
• Supply Current: 1.4mA
• Digital Ic Case Style: TSSOP
• No. Of Pins: 24
• Operating Temperature Range: -40°C To +125°C
• Rohs Compliant: Yes
• 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: *LM81CIMT-3; *LM81CIMT-3/NOPB; LM81CIMT-3

Functional Description
Interrupt source. In addition, the Configuration Register has
a control bit to enable or disable the hardware Interrupt.
Another hardware Interrupt line available T_CRIT_A (Critical
Temperature Alarm Output) is used to signal a catastrophic
overtemperature event. Having a dedicated interrupt for this
2.0 INTERFACE
(Continued)
FIGURE 4. LM81 Register Structure
11
purpose allows for the fastest possible response time to a
thermal runaway event. This output can be enabled by set-
ting bit 4 of Extended Mode Register 1.
The Chassis Intrusion input is designed to accept an active
high signal from an external circuit that latches when the
case is removed from the computer.
DS100072-7
www.national.com