Thermistors

• Thermistor


  A type of resistor whose resistance decreases as temperature increases
• As temperature increases


  Resistance of a thermistor decreases
• Applications of thermistors

  • Thermostats
  • Computers (to control fan speed)
• How thermistors work in computers

  1. Under cool conditions, high resistance of thermistor means low current and low potential difference across fan, so fan runs at low speed

  2. Under hot conditions, low resistance of thermistor means high current and high potential difference across fan, so fan runs at high speed to cool computer
• Other applications of thermistors

  • Incubators for premature babies (to detect temperature drops and turn on heating lamp)