Circuit board NOOB, What is this part and where can I find a replacement

Discussion in 'General Electronics Chat' started by Sgt_Strife, Oct 8, 2013.

  1. Sgt_Strife

    Thread Starter New Member

    Oct 8, 2013
    I took apart my Lacie 500 GB d2 Quadra external hard drive and I found that one of the parts fried.

    I don't know what the part is called, nor if I did, I don't know where to order a new one.

    It's a very small black rectangle with "218A" printed on it. It also has 3 pins.
    I have other random circuit boards laying around, but I can't find the same "218A" in them, they look the same. But I am so unfamiliar with circuit boards I'd be guessing by soldering it in there.

    Again my questions are: 1) What is the part called and 2) where can I find a replacement?
  2. PackratKing

    Well-Known Member

    Jul 13, 2008
    Appears to be a SMD transistor... prpriertary to the device the PCB is in...
  3. Sgt_Strife

    Thread Starter New Member

    Oct 8, 2013
    Any way to find a replacement?
  4. paulktreg

    Distinguished Member

    Jun 2, 2008
    If there's important data on the HDD that you need I'd be looking for an identical HDD and swapping out the boards?
  5. Meixner


    Sep 26, 2011
    use an ohmmeter to check one of the good transistors with the same marking. try to determine if it is a NPN or PNP transistor. Then replace it with a switching transistor with the same pinout. Possibly MMBT3904 or MMBT3906 would work.
  6. #12


    Nov 30, 2010
    Don't rule out the idea that it might be a mosfet.
    It would be good luck if it turned out to be a simple bipolar transistor.