 2001-2012 Microchip Technology Inc.

DS21450D-page 1

TC650/TC651

Features

• Integrated Temperature Sensing and Multi-speed

Fan Control

• Temperature-proportional Fan Speed Control for

Acoustic Noise Reduction and Longer Fan Life

• Pulse Width Modulation (PWM) Output Drive for

Cost and Power Savings

• Solid-state Temperature Sensing

•±1

C (typ.) Accuracy from 25C to +70C

• Operating Range: 2.8V – 5.5V

• TC651 includes Automatic Fan Shutdown

• Low Operating Current: 50 µA (typ.)

Applications

• Thermal Protection For Personal Computers

• Digital Set-Top Boxes

• Notebook Computers

• Data Communications

• Power Supplies

•Projectors

Related Literature

• Application Note 771 (DS00771)

General Description

The TC650/TC651 are integrated temperature sensors

and brushless DC fan speed controllers. The TC650/

TC651 measure the junction temperature and control

the speed of the fan based on that temperature, making

them especially suited for applications in modern

electronic equipment.

Temperature data is converted from the on-chip

thermal sensing element and translated into a

fractional fan speed from 40% to 100%. A temperature

selection guide in the data sheet is used to choose the

low and high temperature limits to control the fan. The

TC650/TC651 also include a single trip point over-

additional temperature sensors. In addition, the TC651

features an auto fan shutdown function for additional

power savings.

The TC650/TC651 are easy to use, require no software

overhead and are, therefore, the ideal choice for

implementing thermal management in a variety of

systems.

Package Type

1

8

27

3

6

4

5

NC

PWM

NC

GND

8-Pin MSOP

SHDN

GND

TC650

TC651

Tiny Integrated Temperature Sensor & Brushless DC Fan

Controller with Overtemperature Alert