TC650/TC651 Tiny Integrated Temperature Sensor & Brushless DC Fan Controller with Overtemperature Alert Features General Description Integrated Temperature Sensing and Multi-speed The TC650/TC651 are integrated temperature sensors Fan Control and brushless DC fan speed controllers. The TC650/ TC651 measure the junction temperature and control Built-in Overtemperature Alert (T ) OVER the speed of the fan based on that temperature, making Temperature-proportional Fan Speed Control for them especially suited for applications in modern Acoustic Noise Reduction and Longer Fan Life electronic equipment. Pulse Width Modulation (PWM) Output Drive for Temperature data is converted from the on-chip Cost and Power Savings thermal sensing element and translated into a Solid-state Temperature Sensing fractional fan speed from 40% to 100%. A temperature 1 C (typ.) Accuracy from 25 C to +70 C selection guide in the data sheet is used to choose the Operating Range: 2.8V 5.5V low and high temperature limits to control the fan. The TC651 includes Automatic Fan Shutdown TC650/TC651 also include a single trip point over- temperature alert (T ) that eliminates the need for Low Operating Current: 50 A (typ.) OVER additional temperature sensors. In addition, the TC651 features an auto fan shutdown function for additional Applications power savings. Thermal Protection For Personal Computers The TC650/TC651 are easy to use, require no software Digital Set-Top Boxes overhead and are, therefore, the ideal choice for Notebook Computers implementing thermal management in a variety of systems. Data Communications Power Supplies Package Type Projectors 8-Pin MSOP Related Literature V 8 PWM Application Note 771 (DS00771) DD 1 NC27 GND TC650 TC651 3 6 SHDN T OVER 4 5 NC GND 2001-2012 Microchip Technology Inc. DS21450D-page 1TC650/TC651 Typical Application Circuit +12V PIC Microcontroller +5V V DD DC Fan TC650 500 mA TC651 V 1 PWM 8 DD C SLOW 27NC GND SHDN T 3 6 SHDN OVER Control NC 4 GND 5 GND GND Overtemperature Alert DS21450D-page 2 2001-2012 Microchip Technology Inc.