MAX6639, MAX6639F:2-Channel Temperature Monitor with Dual, Automatic, PWM Fan-Speed Controller

High-Frequency, Dual Temperature Sensor and Fan Controller with Selectable Address and Closed-Loop Operation

The MAX6639 monitors its own temperature and one external diode-connected transistor or the temperatures of two external diode-connected transistors, typically available in CPUs, FPGAs, or GPUs. The 2-wire serial interface accepts standard System Management Bus (SMBus) write byte, read byte, send byte, and receive byte commands to read the temperature data and program the alarm thresholds. Temperature data can be read at any time over the SMBus, and three programmable alarm outputs can be used to generate interrupts, throttle signals, or overtemperature shutdown signals. The temperature data is also used by the internal dual-PWM fan-speed controller to adjust the speed of up to two cooling fans, thereby minimizing noise when the system is running cool, but providing maximum cooling when power dissipation increases. Speed control is accomplished by tachometer feedback from the fan, so that the speed of the fan is controlled, not just the PWM duty cycle. Accuracy of speed measurement is ±4%. The MAX6639 is available in 16-pin QSOP and 16-pin thin QFN 5mm x 5mm packages. It operates from 3.0V to 3.6V and consumes just 500µA of supply current.

Key Features
  • Two Thermal-Diode Inputs
  • Up to 25kHz PWM Output Frequency
  • Three Selectable SMBus Addresses
  • Local Temperature Sensor
  • 1°C Remote Temperature Accuracy
  • Two PWM Outputs for Fan Drive (Open Drain; Can be Pulled Up to +13.5V)
  • Programmable Fan-Control Characteristics
  • Automatic Fan Spin-Up Ensures Fan Start
  • Controlled Rate-of-Change Ensures Unobtrusive Fan-Speed Adjustments
  • ±3% Fan-Speed Measurement Accuracy
  • Temperature Monitoring Begins at POR for Fail-Safe System Protection
  • Active-Low OT and Active-Low THERM Outputs for Throttling or Shutdown
  • Measures Temperatures Up to +150°C
  • MAX6639F is Optimized for n = 1.021 for Penryn Compatibility
MAX6639: Typical Application Circuit
MAX6639: Typical Application Circuit
Applications/Uses
  • Desktop Computers
  • Networking Equipment
  • Notebook Computers
  • Projectors
  • Servers
DataSheet
titleDownload file
MAX6639-MAX6639F Data SheetMAX6639-MAX6639F.pdf
Parametrics
Part NumberSensor TypeFan Controller FunctionsFan Cntrl.InterfaceAccuracy
(±°C)
Temp. Thresh.
(°C)
Package/PinsBudgetary
Price
See Notes
MAX6639RemoteRemote & Local SensorPWM2-Wire/I2C/SMBus1ProgrammableQSOP/16
TQFN/16
$1.67 @1k
Design kits & evaluation modules
Quality and Environmental Data
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX6639AEENo Longer AvailableMAX6639AEE+QSOP,;16 pin;30.9 mm²-40°C to +125°CNo
MAX6639AEE+ActiveQSOP,;16 pin;30.9 mm²-40°C to +125°CLead Free
MAX6639AEE+TActiveQSOP,;16 pin;30.9 mm²-40°C to +125°CLead Free
MAX6639AEE-TNo Longer AvailableMAX6639AEE+TQSOP;16 pin-40°C to +125°CSee data sheet
MAX6639ATENo Longer AvailableMAX6639ATE+TQFN,;16 pin;26 mm²-40°C to +125°CNo
MAX6639ATE+ActiveTQFN,;16 pin;26 mm²-40°C to +125°CLead Free
MAX6639ATE+TActiveTQFN,;16 pin;26 mm²-40°C to +125°CLead Free
MAX6639ATE-TNo Longer AvailableMAX6639ATE+TQFN;16 pin-40°C to +125°CSee data sheet
MAX6639FAEE+ActiveQSOP,;16 pin;30.9 mm²-40°C to +125°CLead Free
MAX6639FAEE+TActiveQSOP,;16 pin;30.9 mm²-40°C to +125°CLead Free
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX6639FATE+ActiveTQFN,;16 pin;26 mm²-40°C to +125°CLead Free
MAX6639FATE+TActiveTQFN,;16 pin;26 mm²-40°C to +125°CLead Free
MAX6639YAEE+ActiveQSOP,;16 pin;30.9 mm²-40°C to +125°CLead Free
MAX6639YAEE+TActiveQSOP,;16 pin;30.9 mm²-40°C to +125°CLead Free
MAX6639-MAX6639F.pdf MAX6639F
MAX6639-MAX6639F.pdf MAX6639F
MAX6639-MAX6639F.pdf MAX6639F
Understanding Multidrop Address Assignments for Thermal Sensors MAX7504
Introduction to Medical Instruments and Growing Trend for Point-of-Care and Near-Patient Testing MAX31820PAR
Circuit Converts PWM Fan Drive to Linear and Reduces Acoustic Noise MAX6653
MAX6639.pdf MAX6639F