LM91 - Diode Input Digital Temperature Sensor with Two-Wire Interface [Obsolete]
Datasheet Obsolete Versions Knowledge Base

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 LM91s to be connected to a single bus

Key Specification


Supply Voltage3.0V - 3.6V
Supply Current1 mA (max)
Local Temperature Accuracy±1.0°C (typ)
Remote Diode Temperature Accuracy 
+60°C to +100°C±4°C (max)
0°C to +125°C±6°C (max)

General Description


The LM91 is a remote diode temperature sensor, Delta-Sigma analog-to-digital converter, and digital over-temperature detector with an SMBus™ interface. More...


Applications


System Thermal Management
Personal Computers
Electronic Test Equipment
Office Electronics
HVAC
  Typical Application
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  Block Diagram
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Datasheet
RoHS Compliance Information Size in KbytesDate Click link below to Download
LM91 Diode Input Digital Temperature Sensor with Two-Wire Interface 184
Kbytes
27-Nov-01 Download

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Obsolete Versions

Obsolete PartAlternate Part or SupplierSourceLast Time Buy Date
LM91DIMQA
NONE
NONE
01 Dec 2004
LM91DIMQAX
NONE
NONE
01 Dec 2004

General Description


The LM91 is a remote diode temperature sensor, Delta-Sigma analog-to-digital converter, and digital over-temperature detector with an SMBus™ interface. The LM91 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 LM91 at any time to read the temperature of this diode as well as the temperature state of the LM91 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. Power up default values for T_CRIT are as shown in the ordering information table. Three state logic inputs allow two pins (ADD0, ADD1) to select up to 9 SMBus address locations for the LM91.

[Information as of 8-Nov-2009]