LM80CIMT-3/NOPB National Semiconductor, LM80CIMT-3/NOPB Datasheet - Page 19

• Manufacturer Part Number: LM80CIMT-3/NOPB
• Description: IC MONITOR SYS HARDWAR 24-TSSOP
• Manufacturer: National Semiconductor
• Series: PowerWise®r

Specifications of LM80CIMT-3/NOPB

• Function: Hardware Monitor
• Topology: ADC, Comparator, Fan Speed Counter, Register Bank
• Sensor Type: External & Internal
• Sensing Temperature: -25°C ~ 125°C, External Sensor
• Output Type: I²C™
• Output Alarm: No
• Output Fan: No
• Voltage - Supply: 2.8 V ~ 5.75 V
• Operating Temperature: -25°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 24-TSSOP
• Number Of Voltages Monitored: 7
• Manual Reset: Not Resettable
• Watchdog: Watchdog
• Battery Backup Switching: No
• Power-up Reset Delay (typ): 500 ns
• Supply Voltage (max): 5.75 V
• Supply Voltage (min): 2.8 V
• Supply Current (typ): 200 uA (Typ)
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 25 C
• Power Fail Detection: No
• Ic Output Type: Digital
• Sensing Accuracy Range: ± 3°C
• Supply Current: 200µA
• Supply Voltage Range: 2.8V To 5.75V
• Resolution (bits): 8bit
• Sensor Case Style: TSSOP
• No. Of Pins: 24
• Accuracy %: 3°C
• Rohs Compliant: Yes
• For Use With: LM80EVAL - EVALUATION BOARD FOR LM80
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: *LM80CIMT-3; *LM80CIMT-3/NOPB; LM80CIMT-3

8.0 THE LM80 INTERRUPT STRUCTURE
Figure 10
LM80 can generate Interrupts as a result of each of its internal
WATCHDOG registers on the analog, temperature, and fan
inputs.
8.1 Interrupt Inputs
External Interrupts can come from the following sources.
While the label suggests a specific type or source of Interrupt,
this label is not a restriction of its usage, and it could come
from any desired source:
•
BTI - This is an active low Interrupt intended to come
from the O.S. output of LM75 temperature sensors. The
LM75 O.S. output goes active when its temperature
exceeds a programmed threshold. Up to 8 LM75's can be
connected to a single Serial Bus bus with their O.S.
output's wire or'd to the BTI input of the LM80. If the
temperature of any LM75 exceeds its programmed limit, it
drives BTI low. This generates an Interrupt to notify the
depicts the Interrupt Structure of the LM80. The
FIGURE 10. Interrupt Structure
19
•
•
host of a possible overtemperature condition. Provides an
internal pull-up of 10 kΩ.
CI (Chassis Intrusion) -
from any type of device that detects and captures chassis
intrusion violations. This could be accomplished
mechanically, optically, or electrically, and circuitry
external to the LM80 is expected to latch the event. The
design of the LM80 allows this input to go high even with
no power applied to the LM80, and no clamping or other
interference with the line will occur. This line can also be
pulled low for at least 10 ms by the LM80 to reset a typical
Chassis Intrusion circuit. Accomplish this reset by setting
Bit 5 of Configuration Register high. The bit in the Register
is self-clearing.
INT_IN -
to chain the INT (Interrupt) from other devices through the
LM80 to the processor.
This active low Interrupt merely provides a way
This is an active high interrupt
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