• AD8251, AD8253 Model Convergence


    I am attempting to use the AD825x devices as current sense and voltage sense instrumentation amplifiers in an analog control loop. I was unable to get the SPICE models for the AD825x to work with PSpice and LTSpice. While the circuit simulation was…

  • AD8251 Input Impedance

    AD8250 has differential input impedance  of 5.3Gohms/ 0.5 pf.

    I have input signal whose differential input impedance which is driving AD8250 is  10Mohms & 5pf.

    My customer is saying that i may not be able to give differential signal to AD8250 directly…

  • Spice Model of AD8251


    I simulated the AD8251 in LTspice and found strange input bias current.

    This part's specification of input bias current is 30nA max but it show a much bigger value.

    Would you tell me the reason?

  • Questions about AD8253/AD8251/AD8250 ?


    I wonder if it's enough for AD8253/AD8251/AD8250 to output ±10V when it is supplied with a power of ±12V ?


  • 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 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?

  • 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.


  • AD8251输出差分不稳定


  • AD8251 differential output voltage calculation question

    I would like to use the AD8251 in-amp in the same circuit configuration shown in figure 61 of its datasheet. I have two questions...

    1. I can calculate the in amp and the level shift output voltage equations separately but am having trouble coming up…

  • Several Issues about AD8251+AD8475+AD7982


    I use your company's typical circuit AD8251+AD8475+AD7982 applied to multi-channel acquisition.

    1.The test attachment figure. when the AD8251 input +5V, gain1, AD8475 input +5V, the AD8475 gain is connected to the IN0.4X pin, the AD7982 output…