Overview
The ADT7490ARQZ-REEL7, produced by onsemi, is a comprehensive thermal monitor and multiple PWM fan controller designed for systems that require active cooling and precise thermal management. This device is particularly suited for noise-sensitive or power-sensitive applications. It integrates a local temperature sensor, two remote temperature sensors with series resistance cancellation, and supports CPU temperature monitoring via the Platform Environment Control Interface (PECI).
The ADT7490 offers advanced fan control capabilities, including the ability to drive and monitor the speed of up to four fans, optimizing their operation for minimal acoustic noise. It also features automatic fan speed control based on thermal information and provides critical thermal protection through its bidirectional THERM/SMBALERT pin.
Key Specifications
| Parameter | Unit | Min | Typ | Max | Conditions |
|---|---|---|---|---|---|
| Supply Voltage (VCC) | V | 3.0 | 3.3 | 5.5 | |
| Supply Current (ICC) | mA | 0.5 | 0.8 | ||
| Standby Current (ICC) | µA | 4 | |||
| Total Unadjusted Error (TUE) for Local Temperature | % | ±2 | −40°C ≤ TA ≤ +125°C | ||
| Differential Non-linearity (DNL) for ADC | LSB | ±1 | 8 Bits | ||
| Input High Voltage (VIH) for Digital Inputs | V | 2.0 | 5.5 | ||
| Input Low Voltage (VIL) for Digital Inputs | V | −0.3 | 0.8 |
Key Features
- Temperature Measurement: Includes one local on-chip temperature sensor, two remote temperature sensors with series resistance cancellation, and supports up to four PECI inputs for CPU thermal information.
- Fan Drive and Fan Speed Control: Provides three high-frequency or low-frequency PWM outputs for 3-wire or 4-wire fans and four TACH inputs to measure fan speed. Features OS-independent automatic fan speed control and dynamic TMIN control mode to optimize system acoustics.
- Bidirectional THERM/SMBALERT Pin: Flags out-of-limit and overtemperature conditions and can be used for clock modulation purposes.
- GPIO Functionality: Supports extra features such as loadline setting for voltage regulation, LED control, or other functions.
- IMON Monitoring: Monitors CPU current and power information.
- PECI Interface: Reads CPU thermal information through the PECI interface, supporting up to four PECI addresses.
Applications
The ADT7490 is designed for various applications requiring precise thermal monitoring and active cooling, including:
- Noise-sensitive systems where minimal acoustic noise is crucial.
- Power-sensitive systems that require efficient cooling solutions.
- Server and data center environments where multiple fans need to be controlled and monitored.
- High-performance computing systems that demand advanced thermal management.
- Industrial and embedded systems requiring robust thermal monitoring and fan control.
Q & A
- What is the primary function of the ADT7490?
The ADT7490 is a thermal monitor and multiple PWM fan controller designed for systems requiring active cooling and precise thermal management.
- How many temperature sensors does the ADT7490 support?
The ADT7490 includes one local on-chip temperature sensor and two remote temperature sensors with series resistance cancellation.
- What is the PECI interface used for in the ADT7490?
The PECI interface is used to read CPU thermal information, supporting up to four PECI addresses.
- How many fans can the ADT7490 control and monitor?
The ADT7490 can control and monitor the speed of up to four fans.
- What is the purpose of the THERM/SMBALERT pin?
The THERM/SMBALERT pin flags out-of-limit and overtemperature conditions and can be used for clock modulation purposes.
- Does the ADT7490 support GPIO functionality?
- How does the ADT7490 optimize fan speed?
The ADT7490 optimizes fan speed using automatic fan speed control based on thermal information from the PECI, remote, or local temperature sensors.
- What communication interface does the ADT7490 use?
The ADT7490 communicates with the system via a serial system management bus, supporting SMBus and fast I2C specifications.
- What is the supply voltage range for the ADT7490?
The supply voltage range for the ADT7490 is from 3.0 V to 5.5 V.
- Does the ADT7490 have standby current specifications?
