making hall sensor out of hall element

Discussion in 'The Projects Forum' started by egypte, Sep 11, 2013.

  1. egypte

    Thread Starter New Member

    Sep 4, 2013

    I'm searching for a hall sensor to measure a magnetic field up to around 1T - 1.5T.

    Does someknow know any hall effect sensor to measure this?

    If not, I think there is no other possibility to use this hall element The problem is that this is a hall element and not a 'prepared' hall IC.

    Does anyone know how I can make a stable hall effect sensor out of the hall element? I can see in the PDF (circuit 2) that I will need 2 power supplies ( to create + and - voltage) and some kind of opamp. (which one?) Do I need other things (capacitor, resistors,...) to ensure good and stable measurements of the magnetic field? The sensor will be connected to a multimeter.
    Last edited by a moderator: Sep 12, 2013
  2. Experimentonomen


    Feb 16, 2011
    Look for analog hall sensors.
  3. egypte

    Thread Starter New Member

    Sep 4, 2013
    you mean to buy or for the circuit? Because there are no 1T analog hall sensors, only hall elements.
  4. shortbus

    AAC Fanatic!

    Sep 30, 2009
    From what I read in your link, it's all in there, on how to do it. While it doesn't give an opamp part number, it tells you what to Google for. I don't know enough about opamps to advise you but, it's all in that data sheet.

    Don't quite know why you think you need two different power supplies for the hall. It just is saying which pins are wired to the positive and negative of the supply. But depending on the opamp you choose they need a negative and positive supply. But that is a simple thing to do, Google "dual rail power supply" or use the search here to find many ways of doing it.
  5. egypte

    Thread Starter New Member

    Sep 4, 2013
    In order to put the offset to 0 I need +5V and -5V. If I use +5V and 0V then there will be an offset according to the document.

    I guess I could just use something like the left circuit..(see below)
    I see in the document that B(T) = V_H/2 for Ic = 5 mA. So if I give 5mA and -5mA to the hall sensor (using a current source) and put R2/R1 = 5, the 10V on my multimeter is the same as 1T.

    How do I determine R1 or R2 and is the MC33171PG opamp good enough for this?