LM64 1 remote and local temp sensor with fan control and 5 voltage monitors | TI.com

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1 remote and local temp sensor with fan control and 5 voltage monitors



The LM64 is a remote diode temperature sensor with PWM fan control. The LM64 accurately measures its own temperature and that of a remote diode. The LM64 remote temperature accuracy is factory trimmed for a MMBT3904 diode-connected transistor with a 16°C offset for high temperatures. TACTUAL DIODE JUNCTION = TLM64 + 16°C

The LM64 features a PWM, open-drain, fan control output, 5 GPIO (General Purpose Input/Output) and 5 GPD (General Purpose Default) pins. The 8-step Lookup Table allows for a non-linear fan speed vs. temperature transfer function often used to quiet acoustic fan noise.


  • Accurately Senses Remote and Local Diode Temperatures
  • Integrated PWM Fan Speed Control Output
  • Programmable 8-step Lookup Table for Quieting Fans
  • ALERT and T_Crit Open-drain Outputs
  • Tachometer Input for Measuring Fan RPM
  • 10 bit Plus Sign Remote Diode Temperature Data Format, with 0.125°C Resolution
  • SMBus 2.0 Compatible Interface, Supports TIMEOUT
  • 5 General Purpose Input/Output pins
  • 5 General Purpose Default input pins
  • 24-pin WQFN Package

Key Specifications

  • Remote Diode Temperature Accuracy (includes quantization error)
    • Ambient Temp30°C to 50°C0°C to 85°C
    • Diode Temp120°C to 140°C 25°C to 140°C
    • Max Error±1.0°C (max)±3.0°C (max)
  • Local Temp Accuracy (includes quantization error)
    • Ambient Temp 25°C to 125°C
    • Max Error ±3.0°C (max)
  • Power Supply Requirements
    • Supply DC Voltage 3.0 V to 3.6 V
    • Supply DC Current 1.1 mA (typ)

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