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TCM1617

TCM1617-1 2/5/99

 2001 Microchip Technology Inc.

DS21485A

SMBus Thermal Sensor with External Diode Input

FEATURES

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Includes Internal External Sensing Capability

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Outputs Temperature as 8-Bit Digital Word

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Solid State Temperature Sensing; 1

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3.0 – 5.5V Operating Range

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Independent Internal and External Threshold

Set-Points With ALERT# Interrupt Output

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SMBus 2-Wire Serial Interface

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Up To Nine TCM1617s May Share the Same Bus

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Standby Mode for Low Standby Power

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Low Power ............................ 70

...................................... 10

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16-Pin Plastic QSOP Package

TYPICAL APPLICATIONS

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Thermal Protection For Intel “Deschutes”

Pentium II™ and Other High Performance CPUs

with Integrated On-Board Diode — No Sensor

Mounting Problems!

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Accurate Thermal Sensing From Any Si Junction

Diode

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Thermal Management in Electronic Systems:

Computers, Network Equipment, Power Supplies

GENERAL DESCRIPTION

The TCM1617 is a serially programmable temperature

sensor optimized for monitoring modern high performance

CPUs with on-board integrated thermal diodes. Tempera-

ture data is converted from the CPU’s thermal diode outputs

and made available as an 8-Bit digital word.

Communication with the TCM1617 is accomplished via

the standard System Management Bus (SMBus) commonly

used in modern computer systems. This permits reading the

current internal/external temperature, programming the

threshold setpoints, and configuring the device. Addition-

ally, an interrupt is generated on the ALERT# pin when

temperature moves outside the preset threshold windows in

either direction.

A Standby command may be sent via the SMBus by

signaling the STBY# input to activate the low-power Standby

mode. Registers can be accessed while in Standby mode.

Address selection inputs allow up to nine TCM1617s to

share the same 2-wire SMBus for multi-zone monitoring.

All registers can be read by the host, and both polled and

interrupt driven systems are easily accommodated. Small

size, low installed cost, and ease of use make the TCM1617

an ideal choice for implementing sophisticated system man-

agement schemes, such as ACPI.

ORDERING INFORMATION

Part No.

Package

Temp. Range

TCM1617MQR

QSOP-16

–55

°C to +125°C

TCM1617EV

Evaluation Kit for TCM1617

BLOCK DIAGRAM

PIN CONFIGURATION

EVALUATION

KIT

AVAILABLE

Register Set

∆∑

Modulator

Control

Logic

SMBus

Interface

ALERT#

STBY#

SCL

SDA

ADD 0

ADD 1

Ext. Temp

Status Byte

Config. Byte

Conv. Rate

Ext. Hi Limit

Ext. Lo Limit

Int. Hi Limit

Int. Lo Limit

Int. Temp

Internal

Sensor

(Diode)

16-Pin Plastic QSOP

1

16

215

314

413

512

611

710

NC

D–

89

NC

GND

GND

SCL

STBY#

NC

SDA

ALERT#

ADD0

NC

D+

TCM1617

NC

ADD 1