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Fan controller circuit

  1. Apr 1, 2013 #1
    Last edited by a moderator: Apr 1, 2013
  2. jcsd
  3. Apr 1, 2013 #2
    Your IC1 op amp thing is probably part of a package... look at your chip and most likely it is an 8-pin package.
    Typically the pins count down on the left side and up on the right side if you have it the right way up.

    1 5
    2 6
    3 7
    4 8

    So look at the numbers on the pins.. and put the components in around them.
    R4 runs from pin 2 to ground.
    R3 should be connected at one point to where R4 is connected to the pin.

    is R1 your thermistor?
  4. Apr 1, 2013 #3
    thank you for replying R1 is the thermistor yeah but actually the 741 op amp is


    everything is quite clear except for R4 and the thermistor..there's only 3 holes in the ground area in the layout 1 for the fan 2 for the capacitor and the 3rd should be for either the thermistor or R4 while both of them should be connected..should i dig another hole or something ?!!
    Last edited by a moderator: Apr 1, 2013
  5. Apr 5, 2013 #4
    It is not clear exactly from what you've said. A good idea is probably to take a non-blurry, well lit photo of the circuit as it is at the moment. I should be able to see clearly on that and help you further :)
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