LM81BIMT-3/NOPB National Semiconductor, LM81BIMT-3/NOPB Datasheet - Page 3

• Manufacturer Part Number: LM81BIMT-3/NOPB
• Description: IC MONITOR SYS HARDWARE 24TSSOP
• Manufacturer: National Semiconductor

Specifications of LM81BIMT-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: *LM81BIMT-3; *LM81BIMT-3/NOPB; LM81BIMT-3

A0/NTEST_OUT
A1
SMBData
SMBCLK
FAN1-FAN2
CI
T_CRIT_A
V
+3.8V)
+
Block Diagram
Pin Description
(+2.8V to
Name(s)
Pin
Number
Pin
5-6
1
2
3
4
7
8
9
Number
of Pins
1
1
1
1
2
1
1
1
Digital I/0
Digital Input
Digital I/O
Digital Input
Digital Inputs
Digital I/O
Digital Output
POWER
Type
The lowest order programmable bit of the serial bus address. This
pin functions as an output during NAND Tree tests (board-level
connectivity testing). Refer to SECTION 11 on NAND Tree testing.
The highest order programmable bit of the serial bus address.
Serial Bus bidirectional Data. Open-drain output.
Serial Bus Clock.
Schmitt Trigger fan tachometer inputs.
An active high input from an external circuit which latches a
Chassis Intrusion event. This line can go high without any
clamping action regardless of the powered state of the LM81.
There is also an internal open-drain output on this line, controlled
by Bit 6 of the Configuration Register (40h) or Bit 7 CI Clear
Register (46h), to provide a minimum 20 ms reset pulse. See
Section 3.3 and Section 9.0 .
Critical Temperature Alarm active low open-drain output. This pin
can be grounded when not used.
+3.3V V
(electrolytic or tantalum) and 0.1 µF (ceramic) bypass capacitors.
3
+
power. Bypass with the parallel combination of 10 µF
Description
DS100072-2
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