Can op-amp be used with one terminal open?

Discussion in 'General Electronics Chat' started by Wtech, Nov 4, 2009.

  1. Wtech

    Thread Starter New Member

    Apr 27, 2009
    Greetings guys
    I have a problem with a circuit I am working on, there on the schematic the op-amp has its inverting input pin open. The non-inverting input is connected though. Can it be used this way? What can be the expected working of the op-amp in this configuration?
  2. Eduard Munteanu

    Active Member

    Sep 1, 2007
    Don't let that input unconnected. Aside from the fact you're probably not providing any negative feedback, the circuit will probably not work reliably with a floating input. You should review op-amp materials and see the basic ways of connecting them.

    Even if you have high-Z outputs that go into inputs, you need pull-up/pull-down resistors.
  3. StayatHomeElectronics

    Well-Known Member

    Sep 25, 2008
    Can you post the schematic? As Eduard has pointed out, using an op amp with an open input does not seem correct...