• AD8221

    How can I implement an RFI input filter and an DC return path together for the AD8221? The IA is used to amplify an very small signal (tens of uV) provided from a electromagnetic flowmeter. This voltage is generated from the ions in the liquid.Thanks

  • AD8221 output impedance

    Could you please provide me data on the resistance of the output path of the


    The output resistance is quite low at dc and low frequencies. Approximately 0.1
    ohms until the short circuit current limit kicks in above about 18mA…
  • AD8221和AD8429


  • AD8221 Problem


    I am using an AD8221 to amplify a wheatstone bridge.  I believe I have the circuit configured correctly (nothing fancy), I even added a couple of resistors between -IN and +IN to Ground.

    For some reason my output reads 635 mV when it should…

  • AD8221: Driving capacitive loads

    Can you say advise about stability of the AD8221 at capacitive loads. Which
    capacitive load is acceptable?


    The settling time plots in the datasheet are all done with a 100pF load, and
    the part is very stable with this much capacitance…
  • AD8221 Input Bias Current

    How did you come up with the 100GOhm specification for input bias current for


    Essentially, it is the change in voltage at the input divided by the change in
    input bias current.

    Delta Vcm/ Delta Ib = Input Impedance.

    See Figure 9…

  • AD8221 spurious DC offset

    I am using the AD8221 with +/- 15V supply. I recently put new amplifiers on my board and on power up with no applied input signal the output of one of the amplifiers is ~2.5VDC. Another amplifier has a similar problem with a different output voltage,…

  • AD8221 at 3.3V

    Hi everyone, I'm choosing a low noise in-amp for an EEG project. I've found that AD8221 has the best noise characteristics for my set up.

    Unfortunately it requires at least +-2.3V, I am running at 3.3V.

    I've tested an AD620 which is very similar…

  • AD8221 oscillation problem


    I have oscillation problem in ADD8221 circuit, here is the circuit info:

    1 Supply : +15V, -15 V

    2 Input signal, for test: 1.5KHZ, 5 Vp-p

    3 AD8221 gain set to 1

    4 This will work in a circuit range from 10V to -10V in put signal, to get the…