ADT7476AARQZ-REEL7

Thermal Management Overview

The ADT7476AARQZ-REEL7 is a remote thermal controller and voltage monitor manufactured by onsemi. It operates within a supply voltage range of 3.0 V to 3.6 V with a typical supply current of 1.5 mA. The device features an internal temperature sensor and supports two remote diode sensors, providing local accuracy of ±0.5°C at 25°C and up to ±2.5°C across the extended operating temperature range of -40°C to +125°C. It monitors up to five voltages including VCC, +5VIN, +12VIN, +2.5VIN, and VCCP. The component controls and monitors up to four fans via PWM outputs and TACH inputs, communicating through an SMBus interface compliant with version 2.0 specifications.

Thermal Management Feature Summary

• Monitors system temperatures using one internal sensor and two external remote diodes for comprehensive thermal management.
• Controls up to four cooling fans with automatic speed regulation based on measured temperature data.
• Provides hardware-level thermal protection through a bidirectional THERM pin capable of signaling overtemperature conditions.
• Supports high and low frequency drive signals for fan control while maintaining compliance with SMBus 2.0 electrical standards.

Thermal Management Applications

• Noise-sensitive computer systems requiring active cooling optimization
• Power-sensitive applications utilizing automatic fan speed control loops
• Systems monitoring Intel Pentium 4 processor performance impact
• Hardware requiring critical thermal protection against component overheating

Thermal Management Procurement Notes

Verify the specific ordering suffix REEL7 corresponds to tape and reel packaging when sourcing components. Confirm that the device status remains obsolete or limited availability as indicated in distributor records. Ensure compatibility with existing SMBus master controllers regarding address selection logic and timing requirements before finalizing procurement decisions.

Thermal Management Selection Notes

Select this component for designs requiring integrated voltage monitoring alongside thermal control functions. The QSOP-24 package accommodates multiple fan tachometer and PWM connections. Consider the extended temperature measurement capabilities and acoustic enhancement features if minimizing user-perceived noise changes is a priority. Verify power supply constraints align with the specified 3.0 V to 3.6 V operating range.

Thermal Management Part Context

This part belongs to the ADT7476 series of thermal controllers produced by onsemi. It serves as a successor to earlier models like the ADT7468, offering improved temperature accuracy and simplified power-up routines. The device integrates analog-to-digital conversion and limit comparison logic to replace discrete monitoring solutions. It is designed specifically for motherboard implementations where space efficiency and multi-channel monitoring are required.

Thermal Management Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. The ADT7476A is listed as obsolete; verify current stock levels or alternative discontinued parts with similar pinouts and functionality through official manufacturer channels.