• RE: AD8251, AD8253 Model Convergence

    Any model update on AD8251 ? I failed to run the spice simulation with AD8251 using ltspice.

  • Varying input impedance of AD8251

    I am using an AD8251 to measure the amplitude of an AC signal across a sense resistor.  The input impedance of the AD8251 is in parallel with my sense resistor.  Under normal operation, the circuit works great, but when I use large amplitude or high frequency…

  • AD8251 in CN0385 does not work when measuring the ac signal across a resistor at 1MHz

    Hi, I try to measure a AC signal across a resistor at 1MHz using reference design CN0385, where the difference signals (with relatively a large common mode voltage) are converted to single-ended using AD8251. I build this schematic using LTSpice.

  • AD8251 Input Bias Current Model

    Spec sheet for AD8251 cites nA input bias currents.

    I have a rather simple AD8251 simulation running in LTspice (wrapping the AD model) and it is modeling ~4.5uA of input bias current.

    Any suggestions?

  • RE: Dual AD620 sharing same resistor.

    Hi josiah47,

    I'm glad to help. If there is an evaluation board, it looks like it's not available on the web. There is an eval board for a pin-compatible part: the AD8251. http://www.analog.com/en/specialty-amplifiers/instrumentation-amplifiers…

  • RE: AD8251输出差分不稳定


  • Input capacitance measurement for AD8251

    Hi All,

    I am going to use programmable gain amplifier AD8251 in a data acquisition system.

    I want to know how to measure input impedance and capacitance of AD8251 when it present in circuit.

    Please anybody suggest me as soon as possible.


  • RE: AD8251 differential output voltage calculation question

    Harry, thanks for the link to the tool, however what I am looking for is how was the Vout = Vin/2+Vref formula was derived for the circuit.

    I'm trying to calculate the same formula for the AD8251 Vout given the circuit topology in figure 61 but am confused…

  • RE: Is it possible to set AD9959 eval board generate lower frequencies

    Since you are operating below 2MHz, perhaps an instrumentation amplifier would be good?  The only parts we have that might have enough bandwidth are the AD8250, AD8251, and AD8253, however these parts have fixed gains which do not include 28x.  The AD8250…

  • RE: Spice Model of AD8251


    We will look into this.

    Also, can we know what specific application you want to use AD8251?