ADT7490ARQZ-REEL

Thermal Management Overview

The ADT7490ARQZ-REEL is a remote thermal monitor and fan controller manufactured by onsemi, housed in a 24-lead QSOP package. It operates within a supply voltage range of 3.0 V to 3.6 V with a typical supply current of 5.0 mA. The device features one local temperature sensor, two remote diode sensors, and supports up to three external sensors with series resistance cancellation. It includes a PECI interface for CPU thermal monitoring and provides three PWM outputs for driving fans while measuring speeds via four TACH inputs.

Thermal Management Feature Summary

• Integrates a Platform Environment Control Interface (PECI) for direct CPU thermal data acquisition and automatic fan speed control based on processor temperature.
• Supports dynamic minimum temperature control to optimize system acoustics and minimize acoustic noise during operation.
• Features bidirectional THERM/SMBALERT pin functionality to signal out-of-limit conditions and prevent component overheating.
• Includes GPIO pins configurable for loadline setting, LED control, or other system-specific functions.

Thermal Management Applications

• Personal computers requiring active cooling
• Server systems needing precise thermal management
• Noise-sensitive electronic environments

Thermal Management Procurement Notes

Verify the specific REEL suffix against the manufacturer's official documentation to confirm packaging specifications. Confirm that the QSOP-24 footprint matches the target PCB design. Ensure compatibility with the system's SMBus addressing requirements before integration.

Thermal Management Selection Notes

Select this component when PECI-based CPU thermal monitoring is required alongside multi-fan control. It serves as a pin-compatible alternative to the ADT7473/ADT7475/ADT7476/ADT7476A family. Verify that the operating temperature range meets the application's environmental constraints.

Thermal Management Part Context

This part belongs to the ADT7490 family of thermal monitors and fan controllers. It is designed for applications where active cooling is necessary but acoustic performance is critical. The device integrates multiple sensing capabilities and control loops into a single IC.

Thermal Management Replacement Considerations

The ADT7490 is footprint and register compatible with the ADT7473, ADT7475, ADT7476, and ADT7476A families. These parts may serve as functional substitutes if PECI support is not required.

Thermal Management FAQ

How does the ADT7490 handle CPU thermal information?

It utilizes a PECI interface to read CPU thermal data, which can then be used in automatic fan speed control algorithms to adjust cooling based on processor temperature.

What is the function of the THERM/SMBALERT pin?

This bidirectional pin can be configured to signal out-of-limit conditions or overtemperature events, providing critical thermal protection for the system.