MAX6670:Remote Temperature Switches with Integrated Fan Controller/Driver

The MAX6668/MAX6670 remote-junction thermal switches with an internal power transistor drive a cooling fan rated for supply voltages up to +12V and 250mA. These devices measure the temperature of an external P-N junction (typically a diode-connected transistor) and turn on the fan power switch when the remote temperature rises above a factory-programmed threshold. Self-contained and requiring no software development, the MAX6668/MAX6670 are simple “drop-in” fan-control solutions for a variety of systems. The MAX6670 features an open-drain active-low WARN output that goes active when the remote temperature exceeds the factory-programmed fan activation threshold by +15°C. The MAX6670 features an open-drain OT output that goes active when the remote temperature exceeds the factory-programmed threshold by +30°C. The MAX6668/MAX6670 provide a fan-control input, active-low FORCEON, that allows the fan to be driven externally, regardless of temperature. Available temperature thresholds range from +40°C to +75°C in 5°C increments. Hysteresis is preset to 8°C on the MAX6668 or pin selectable to 4°C, 8°C, or 12°C using a three-level logic input on the MAX6670. Temperature threshold accuracy is ±1°C (typ) and ±2.2°C (max) for remote-junction temperatures from +40°C to +75°C. The MAX6668/MAX6670 operate from a +3V to +3.6V power supply, and are specified over the automotive temperature range (-40°C to +125°C). The MAX6668 is offered in an 8-pin µMAX package and the MAX6670 is available in a space-saving 10-pin µMAX package.

Key Features
  • +12V, 250mA Integrated Fan Driver
  • No Calibration Required
  • Pin-Selectable 4°C, 8°C, or 12°C Hysteresis (MAX6670)
  • Factory-Programmed Temperature Thresholds from +40°C to +75°C
  • Overtemperature Warning Signals
  • 110µA (typ) Supply Current
  • Space-Saving 8-Pin and 10-Pin µMAX Packages
MAX6668, MAX6670: Typical Operating Circuit
MAX6668, MAX6670: Typical Operating Circuit
Applications/Uses
  • Card Racks
  • Fan Control
  • Laboratory Instruments
  • Network Hubs, Switches, Routers
  • Notebook and Desktop Computers
  • PC Power Supplies
  • Temperature Alarms
DataSheet
titleDownload file
MAX6668-MAX6670 Data SheetMAX6668-MAX6670.pdf
Parametrics
Part NumberSensor TypeFan Controller FunctionsFan Cntrl.InterfaceAccuracy
(±°C)
Temp. Thresh.
(°C)
Package/PinsBudgetary
Price
See Notes
MAX6670RemoteTemperature Switch/Temperature ComparatorLinearLogic2.2+40
+45
+50
+55
+60
+65
+70
+75
µMAX/10$1.41 @1k
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX6670AUB40No Longer AvailableMAX6670AUB40+µMAX,;10 pin;15.4 mm²-40°C to +125°CNo
MAX6670AUB40+ActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
MAX6670AUB40+TActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
MAX6670AUB40-TNo Longer AvailableMAX6670AUB40+TµMAX,;10 pin;15.4 mm²-40°C to +125°CNo
MAX6670AUB45No Longer AvailableMAX6670AUB45+µMAX,;10 pin;15.4 mm²-40°C to +125°CNo
MAX6670AUB45+ActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
MAX6670AUB45+TActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
MAX6670AUB45-TNo Longer AvailableMAX6670AUB45+TµMAX,;10 pin;15.4 mm²-40°C to +125°CNo
MAX6670AUB50No Longer AvailableMAX6670AUB50+µMAX,;10 pin;15.4 mm²-40°C to +125°CNo
MAX6670AUB50+ActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX6670AUB50+TActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
MAX6670AUB50-TNo Longer AvailableMAX6670AUB50+TµMAX,;10 pin;15.4 mm²-40°C to +125°CNo
MAX6670AUB55No Longer AvailableMAX6670AUB55+µMAX,;10 pin;15.4 mm²-40°C to +125°CNo
MAX6670AUB55+ActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
MAX6670AUB55+TActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
MAX6670AUB55-TNo Longer AvailableMAX6670AUB55+TµMAX,;10 pin;15.4 mm²-40°C to +125°CNo
MAX6670AUB60No Longer AvailableMAX6670AUB60+µMAX,;10 pin;15.4 mm²-40°C to +125°CNo
MAX6670AUB60+ActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
MAX6670AUB60+TActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
MAX6670AUB60-TNo Longer AvailableMAX6670AUB60+TµMAX,;10 pin;15.4 mm²-40°C to +125°CNo
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX6670AUB65No Longer AvailableMAX6670AUB65+µMAX,;10 pin;15.4 mm²-40°C to +125°CNo
MAX6670AUB65+ActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
MAX6670AUB65+TActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
MAX6670AUB65-TNo Longer AvailableMAX6670AUB65+TµMAX,;10 pin;15.4 mm²-40°C to +125°CNo
MAX6670AUB70No Longer AvailableMAX6670AUB70+µMAX,;10 pin;15.4 mm²-40°C to +125°CNo
MAX6670AUB70+ActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
MAX6670AUB70+TActiveµMAX,;10 pin;15.4 mm²-40°C to +125°CLead Free
MAX6670AUB70-TNo Longer AvailableMAX6670AUB70+TµMAX,;10 pin;15.4 mm²-40°C to +125°CNo
MAX6670AUB75No Longer Available-40°C to +125°CSee data sheet
MAX6668-MAX6670.pdf MAX6668
MAX6668-MAX6670.pdf MAX6668
MAX6668-MAX6670.pdf MAX6668