DESCRIPTION

· The ADT7476A is a thermal monitor and multiple PWM fan controller designed for noise-sensitive or power-sensitive applications requiring active system cooling.
· It can drive a fan using either a low or high frequency drive signal and monitor the temperature of up to two remote sensor diodes plus its own internal temperature.
· The device measures and controls the speed of up to four fans, optimizing fan speed for minimal acoustic noise.
· The automatic fan speed control loop adjusts fan speed based on temperature, and the THERM input monitors the system’s thermal solution effectiveness.
· The bidirectional THERM pin provides critical thermal protection to prevent system or component overheating.

FEATURES

· Monitors up to five voltages.
· Improved TACH and PWM performance.
· Controls and monitors up to four fans.
· High and low frequency fan drive signal.
· One on-chip and two remote temperature sensors.
· Extended temperature measurement range up to 191°C.
· Automatic fan speed control mode.
· Enhanced acoustic mode 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.
· 5.0 V support on all TACH and PWM channels.
· Meets SMBus 2.0 electrical specifications.
· Pb-Free, halogen-free, and RoHS compliant.

APPLICATIONS

· Active system cooling in noise-sensitive or power-sensitive environments.
· Thermal management in systems requiring precise fan speed control.
· Overheating prevention in electronic systems.
· Performance monitoring in Intel® Pentium® 4 processor-based systems.