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LM84 Product Folder

Diode Input Digital Temperature Sensor with Two-Wire Interface

See Also:

LM83 - LM83- Triple Remote Diode Input Temperature Sensing

Generic P/N 84

Parametric Table

Temperature Min (deg C)	0000000000.0000
Temperature Max (deg C)	125
Accuracy (+/-) (deg C)	3
Supply Min (Volt)	3
Supply Max (Volt)	3.60
Quiescent Current (mA)	1
RemoteDiode ThermalSensor ()	1
Interface Type	2-Wire Serial

Resolution (bit)	8
Resolution degCperLSB ()	1
Programmable Setpoints	Yes
Shutdown	No
Integrated FanControls ()	-
Interrupt Outputs ()	2
Fault Queue	No

Datasheet

Title	Size in Kbytes	Date	View Online	Download	Receive via Email
LM84 Diode Input Digital Temperature Sensor with Two-Wire Interface	168 Kbytes	2-Mar-01	View Online	Download	Receive via Email
LM84 Diode Input Digital Temperature Sensor with Two-Wire Interface (JAPANESE)	522 Kbytes

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Package Availability, Models, Samples & Pricing

Part Number

Package

Status

Models

Samples &
Electronic
Orders

Budgetary Pricing

Std
Pack
Size

Package
Marking

Type

Pins

MSL/Lead-Free Availability

Lead
Time

Qty

SPICE

IBIS

Qty

$US each

LM84BIMQA

SSOP

Status

Full production

N/A

1K+

$1.50

rail
of
95

NSXYTT
84BI
MQA

11-12 weeks

20000

Obsolete Parts

Obsolete Part	Alternate Part or Supplier	Source	Last Time Buy Date
LM84CIMQA		NONE	03/04/2003
LM84CIMQAX		NONE	03/04/2003

The LM84 is a remote diode temperature sensor, Delta-Sigma analog-to-digital converter, and digital over-temperature detector with an SMBus™ interface. The LM84 senses its own temperature as well as the temperature of a target IC with a diode junction, such as a Pentium® II processor or a diode connected 2N3904. A diode junction (semiconductor junction) is required on the target IC's die. A host can query the LM84 at any time to read the temperature of this diode as well as the temperature state of the LM84 itself. A T_CRIT_A# interrupt output becomes active when the temperature is greater than a programmable comparator limit, T_CRIT.

The host can program as well as read back the state of the T_CRIT register. Three state logic inputs allow two pins (ADD0, ADD1) to select up to 9 SMBus address locations for the LM84. The sensor powers up with default thresholds of 127°C for T_CRIT.

Features

Directly senses die temperature of remote ICs
Senses temperature of remote diodes
SMBus compatible interface, supports SMBus Timeout
Register readback capability
7 bit plus sign temperature data format
2 address select lines enable 9 LM84s to be connected to a single bus

Key Specification

Supply Voltage	3.0V - 3.6V
Supply Current	1 mA (max)
Local Temperature Accuracy	±1.0°C (typ)
Remote Diode Temperature Accuracy
+60°C to +100°C	±3°C (max)
0°C to +125°C	±5°C (max)

Applications

System Thermal Management
Personal Computers
Electronic Test Equipment
Office Electronics
HVAC

Reliability Metrics

Part Number	Process	Early Failure Rate - Rejects	Sample Size (EFR)	PPM *	Rel. Rejects	Device Hours	Long Term Failure Rates (FITS)	MTTF
LM84BIMQA	CS065	0	8800	0	0	600000	6	169643205

For more information on Reliablitity Metrics, please click here.

Design Tools

Title	Size in Kbytes	Date	View Online	Download	Receive via Email
LMxx - Windows 95/98 VXD drivers with stand alone application for talking to temperature sensors or hardware monitors on a mother board	1366 Kbytes	28-Jul-2003	View	Download	Receive via Email

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Application Notes

Title	Size in Kbytes	Date	View Online	Download	Receive via Email
AN-1155: Application Note 1155 A Simple Software I2C Routine for the COP8	82 Kbytes	12-May-00	View Online	Download	Receive via Email

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[Information as of 15-Jan-2004]

LM84 Product Folder