
ON Semiconductor
Remote Thermal Monitor and Fan Controller
The ADT7475 controller is a thermal monitor and multiple PWM fan controller for noise-sensitive or power-sensitive applications requiring active system cooling. The ADT7475 can drive a fan using either a low or high frequency drive signal, monitor the temperature of up to two remote sensor diodes plus its own internal temperature, and measure and control the speed of up to four fans so that they operate at the lowest possible speed for minimum acoustic noise.
FEATUREs
• Controls and Monitors Up to 4 Fans
• High and Low Frequency Fan Drive Signal
• 1 On-Chip and 2 Remote Temperature Sensors
• Extended Temperature Measurement Range, Up to 191°C
• Automatic Fan Speed Control Mode Controls System Cooling Based on Measured Temperature
• Enhanced Acoustic Mode Dramatically Reduces User Perception of Changing Fan Speeds
• Thermal Protection Feature via THERM Output
• Monitors Performance Impact of Intel® Pentium® 4 Processor
• Thermal Control Circuit via THERM Input
• 3-wire and 4-wire Fan Speed Measurement
• Limit Comparison of All Monitored Values
• Meets SMBus 2.0 Electrical Specifications (Fully SMBus 1.1 Compliant)
• These Devices are Pb-Free, Halogen Free/BFR Free and are RoHS Compliant