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.

Features
• Integrated Temperature Sensing and Multi-speed Fan Control
• Built-in Overtemperature Alert (TOVER)
• 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