Please, can you guys help?

Discussion in 'The Projects Forum' started by gutkedu, Oct 10, 2014.

  1. gutkedu

    Thread Starter New Member

    Oct 10, 2014
    Hello guys, I'm having some trouble with a electronic project that my professor gave to me.
    The objective of the project is to create a circuit to turn on a cooler (fan 80mm).
    The especifications are that we need to use a bipolar junction transistor as a temperature sensor, when a warm object ( ex: soldering iron) is approached, the circuit must trigger the cooler. The ideia is to vary the hfe of the transistor to use him in the cut reagion.

    I was trying to make this with a relay, and using the BJT saturation region.

    Sorry for bad english, isnt my native language.
    Hope you guys can help me.
  2. shteii01

    AAC Fanatic!

    Feb 19, 2010
    Lets see schematic.
  3. ronv

    AAC Fanatic!

    Nov 12, 2008

    Vbe also goes down with temperature.
  4. MrChips


    Oct 2, 2009
    Firstly, here are some guidelines to posting on forums.

    Use a subject title that is more useful than "Please, can you guys help?"
    Something like "Temperature controller circuit" would be better.

    Show a schematic of what you are attempting to create.

    All school assignments should begin by showing your efforts.