Analog Devices Inc./Maxim Integrated MAX6664AEE

Overview

The MAX6664AEE from Maxim Integrated is an ACPI-compliant local/remote temperature sensor and PWM fan controller IC designed for thermal management in microprocessor-based systems. It measures its own die temperature (±2°C accuracy, -40°C to +125°C) and remote-PN junction temperature (±1°C from +60°C to +100°C), provides 0.125°C resolution for both channels, drives a PWM fan output with programmable frequency (11.7–93.5 Hz), and asserts THERM on overtemperature events. It is used in server CPU cooling subsystems where autonomous thermal throttling and fan speed regulation are required.

For engineers reviewing the MAX6664AEE datasheet, MAX6664AEE pinout, MAX6664AEE application, or MAX6664AEE equivalent, key selection considerations include remote diode measurement accuracy across +60°C–+100°C, SMBus 2-wire interface timing compliance (10–100 kHz clock, 29–45 ms timeout), open-drain THERM/INT outputs with external pullup requirements, PWM rise/fall time control, and absence of shutdown outputs (SDL/SDR) - distinguishing it from MAX6653AEE.

Technical Context

The MAX6664AEE implements dual-channel delta-sigma ADC architecture for simultaneous local die and remote PN-junction temperature acquisition, with internal biasing of DXP/DXN for differential remote sensing. Its SMBus interface supports Write Byte, Read Byte, Send Byte, and Receive Byte protocols, includes alert response address (0x19) handling, and enforces hardware timeout to prevent bus lockup.

Fan control operates in automatic mode (default), RPM-select mode, or PWM duty-cycle mode - with automatic mode using remote temperature only (unlike MAX6663's dual-temperature option). The THERM output functions as both overtemperature interrupt and external fan-speed override input when pulled low, while INT serves as configurable status interrupt for temperature/fan fault conditions.

Key Specifications

Pinout & Package

MAX6664AEE is housed in a 16-pin QSOP package (5.0 mm × 6.2 mm, 0.65 mm pitch), RoHS-compliant and moisture-sensitive level 1. Pin functions are electrically and functionally identical to MAX6663AEE, differing only from MAX6653AEE by omission of SDL/SDR pins.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar temperature monitor and PWM fan controller applications.

Compared with MAX6663AEE, MAX6664AEE simplifies thermal policy by removing local-temperature influence on automatic fan control - reducing configuration registers and eliminating potential interaction between local sensor drift and fan behavior. Against LM96163CIMTX/NOPB, MAX6664AEE delivers tighter remote accuracy in the critical +60°C–+100°C range and robust SMBus timeout protection essential for server reliability.

Availability

MAX6664AEE is available at Aetrix Electronics and suitable for server thermal management, telecom baseband unit cooling, industrial PLC processor modules, and workstation GPU subsystems requiring stable component supply across extended product lifecycles.

Supply support for MAX6664AEE includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated (now part of Analog Devices) is a semiconductor company specializing in precision analog, mixed-signal, and power management ICs for industrial, computing, and communications markets.

The MAX6664AEE belongs to Maxim's thermal management product line, designed specifically for ACPI-compliant, SMBus-based temperature monitoring and PWM fan control in high-reliability computing platforms.

FAQ

What is the remote temperature measurement accuracy of the MAX6664AEE?

The MAX6664AEE achieves ±1°C remote temperature measurement accuracy over the +60°C to +100°C range when measuring a properly biased remote PN junction. Outside this range - from -25°C to +125°C - accuracy degrades to ±4°C. This specification is validated per Maxim's electrical characteristics table and applies specifically to the MAX6664AEE variant, not the MAX6653AEE or MAX6663AEE.

Does the MAX6664AEE support shutdown outputs like SDL and SDR?

No, the MAX6664AEE does not include SDL or SDR shutdown outputs. These pins are exclusive to the MAX6653AEE. The MAX6664AEE retains only THERM and INT outputs for thermal alerts and interrupts. If hardware-initiated system shutdown based on local or remote overtemperature is required, the MAX6653AEE or MAX6663AEE must be selected instead.

Can the MAX6664AEE's THERM pin be used as an input to force full-speed fan operation?

Yes, the THERM pin on the MAX6664AEE functions as a dual-role I/O: it asserts active-low on overtemperature, and when externally pulled low, it forces the fan to full speed and sets status bit 7 in register 2. This override remains active until status register 2 is read. This behavior is identical across MAX6653AEE, MAX6663AEE, and MAX6664AEE - confirmed in the Functional Description section of the MAX6664AEE datasheet.

What SMBus protocols does the MAX6664AEE support?

The MAX6664AEE supports four standard SMBus protocols: Write Byte, Read Byte, Send Byte, and Receive Byte. It also responds to the SMBus Alert Response Address (0x19) for multimaster arbitration. All timing parameters - including clock frequency (10–100 kHz), setup/hold times, and 29–45 ms timeout - are fully compliant with SMBus 2.0 specifications and verified in the MAX6664AEE Electrical Characteristics table.

How does the MAX6664AEE differ from the MAX6663AEE in automatic fan-control mode?

In automatic fan-control mode, the MAX6664AEE responds solely to remote temperature, while the MAX6663AEE supports dual-input mode - adjusting PWM duty cycle based on the higher of local or remote temperature. This difference is defined in the Fan-Control Mode table (Table 8) and affects configuration register bit [7:5] behavior. MAX6664AEE's simplified single-input algorithm reduces configuration overhead and eliminates cross-channel interaction risks.