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LM90 Product Folder

±3°C Accurate, Remote Diode and Local Digital Temperature Sensor with Two-Wire Interface

Generic P/N 90

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)	1.70
RemoteDiode ThermalSensor ()	1
Interface Type	2-Wire Serial

Resolution (bit)	11
Resolution degCperLSB ()	.1250
Programmable Setpoints	Yes
Shutdown	Yes
Integrated FanControls ()	-
Interrupt Outputs ()	2
Fault Queue	Yes

Datasheet

Title	Size in Kbytes	Date	View Online	Download	Receive via Email
LM90 ±3°C Accurate, Remote Diode and Local Digital Temperature Sensor with Two-Wire Interface	384 Kbytes	19-Feb-02	View Online	Download	Receive via Email
LM90 ±3°C Accurate, Remote Diode and Local Digital Temperature Sensor with Two-Wire Interface (JAPANESE)	285 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

LM90EVAL

evaluation board

Full production

N/A

6 weeks

LM90CIMM

MINI SOIC

Status

Full production

N/A

1K+

$1.20

reel
of
1000

ZXTT
T11C

10-12 weeks

The LM90 is an 11-bit digital temperature sensor with a 2-wire System Management Bus (SMBus) serial interface. The LM90 accurately measures its own temperature as well as the temperature of an external device, such as processor thermal diode or diode connected transistor such as the 2N3904. The temperature of any ASIC can be accurately determined using the LM90 as long as a dedicated diode (semiconductor junction) is available on the target die. The LM90 remote sensor accuracy of ±3°C is factory trimmed for the 1.008 typical non-ideality factor of the mobile Pentium™ III thermal diode. The LM90 has an Offset register to allow measuring other diodes without requiring continuous software management. Contact hardware.monitor.team@nsc.com to obtain the latest data for new processors.

Activation of the ALERT# output occurs when any temperature goes outside a preprogrammed window set by the HIGH and LOW temperature limit registers or exceeds the T_CRIT temperature limit. Activation of the T_CRIT_A# occurs when any temperature exceeds the T_CRIT programmed limit. The LM90 is pin and register compatible with the LM86, Analog Devices ADM1032 and Maxim MAX6657/8.

Features

Accurately senses die temperature of remote ICs or diode junctions
Offset register allows sensing a variety of thermal diodes accurately
On-board local temperature sensing
10 bit plus sign remote diode temperature data format, 0.125 °C resolution
Diode fault detection circuitry
T_CRIT_A# output useful for system shutdown (open diode does not activate T_CRIT_A#)
ALERT# output supports SMBus 2.0 protocol
SMBus 2.0 compatible interface, supports TIMEOUT
8-pin MSOP packages

Key Specification

Supply Voltage	3.0V to 3.6V
Supply Current	0.8mA (typ)
Local Temp Accuracy (includes quantization error)
T_A=25°C to 125°C	±4.0°C (max)
Remote Diode Temp Accuracy (includes quantization error)
T_A=30°C to 50°C, T_D=60°C to 100°C	±3.0°C (max)
T_A=0°C to 85°C, T_D=25°C to 125°C	±4.0°C (max)

Applications

System Thermal Management (e.g. Laptop, Desktop, Workstations, Server)
Electronic Test Equipment
Office Electronics

Reliability Metrics

Part Number	Process	Early Failure Rate - Rejects	Sample Size (EFR)	PPM *	Rel. Rejects	Device Hours	Long Term Failure Rates (FITS)	MTTF
LM90CIMM	CMOS7	2	14200	141	0	800000	5	226190940

For more information on Reliablitity Metrics, please click here.

[Information as of 15-Jan-2004]

LM90 Product Folder

Datasheet

Package Availability, Models, Samples & Pricing

General Description

Features

Key Specification

Applications

Reliability Metrics