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fanTempController.jpg

How to create a temperature controller for a CPU cooling fan (or similar cooling fan for other electronics) only a few bucks and a handful of parts.

Build yourself a fan temperature control [via]

Gareth Branwyn

Gareth Branwyn

Gareth Branwyn is a freelancer writer and the former Editorial Director of Maker Media. He is the author or editor of over a dozen books on technology, DIY, and geek culture. He is currently a contributor for Boing Boing and WINK Books. And he has a new best-of writing collection and “lazy man’s memoir,” called Borg Like Me.


  • Michael Covington

    The MOSFET dissipates no heat when it is fully “off” or “on.” However, in theory, there is a temperature at which the MOSFET will be “half on” and will dissipate heat. How much current does the fan draw under that condition? Is a heat sink needed?

  • Don Hersey

    Yup, Michael C, you are correctly alluding to a weakness in this design. Properly realized, this circuit would include a comparator (w/hysteresis) to make sure the mosfet is truly switched. mosfets have a great deal of process spread, so this is not a ‘good circuit.’
    Without wanting to come off as a latent jerk, it wouldn’t kill a person to read a few books on electronic design. Fairchild’s op amp hand book, the Art of Electronics, ARRL pubs, something!