stops working when its soldered

Discussion in 'The Projects Forum' started by circuitBoy818, May 14, 2014.

  1. circuitBoy818

    Thread Starter New Member

    Dec 13, 2013
    8
    1
    I've been working on a discrete op - amp for my project. It works fine when its on a breadboard, but when i solder it, it stops working. I've built the same thing three items now, and same thing happens. I know that the connections can't be wrong. Does this have to do with the extra capacitance that the breadboard has that the perf board doesn't? which is helping the op amp work better. I can't seem to figure out what the problem is. Any suggestion would be helpful.
     
  2. shortbus

    AAC Fanatic!

    Sep 30, 2009
    4,000
    1,512
    Solder bridges on your board?
     
  3. wayneh

    Expert

    Sep 9, 2010
    12,087
    3,027
    An extra set of eyeballs might see something you're missing. In my experience the thing you "know" is right is usually where the error is.

    Anyway, how about a schematic and a photo?
     
  4. kubeek

    AAC Fanatic!

    Sep 20, 2005
    4,669
    804
    Could be ESD, could be too much heat, could be bad solder joints or bad board design. Like wayneh said, post a schematic and clear photos of the board.
     
  5. w2aew

    Member

    Jan 3, 2012
    219
    64
    ...or it could be oscillating. We need a schematic, photos, and a description of what it is supposed to do...
     
  6. Experimentonomen

    Member

    Feb 16, 2011
    331
    46
    My bet is on you overheating the ic when soldering. Assuming "doesent work" = dead
     
  7. #12

    Expert

    Nov 30, 2010
    16,248
    6,745
    That was my first thought. Capacitance in the right place can stop it from oscillating. Capacitance in the wrong place can make it oscillate. Even some tiny little pfs of capacitance can make all the difference in certain critical positions.

    Schematic and photo, please.
     
  8. DC_Kid

    Distinguished Member

    Feb 25, 2008
    638
    9
    solder in a IC socket, then plug the IC in.
     
  9. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    5,435
    1,305
    90% chance there's a mistake in your soldered version. :)
     
  10. Ramussons

    Active Member

    May 3, 2013
    557
    92
    incorrect counting IC pin numbers.

    Ramesh
     
  11. DC_Kid

    Distinguished Member

    Feb 25, 2008
    638
    9
    its a 8pin DIP package? soldering each pin just once?
    1) what type and wattage iron?
    2) how long does it take for iron on pin to make the solder flow?
    3) what type of board is it?
     
  12. Ramussons

    Active Member

    May 3, 2013
    557
    92
    Start here!



    Ramesh
     
  13. Blackbull

    Well-Known Member

    Jul 26, 2008
    70
    6
    I was hoping the OP would come back on this one, I had the same problem and never did find a solution in spite of successfully making several of the same circuit some years before.
     
Loading...