• AD9027:  Do you have the detail circuit of dither generator using OP27 shown in AD9042 datasheet?

    The following figure is from AD9042 datasheet. Do you have the detail circuit
    of OP27?


    The OP27 circuit we used is just as shown below except the resistor values are
    200 Ohms between pin 11 of the AD600 and pin 2 of the OP27.  The…
  • OP27: Power-supply


    I have a question about the power-supply voltage of OP27.

    Can the OP27 be used in +5V single power supply?

    Best Regards,


  • RE: ADIsimPLL

    Switching the Op-Amp from OP27 to ideal removes the frequency error.

    This is basically the bias current of the op-amp. Lower bias currents give lower frequency error.

  • RE: 关于OP27的供电问题



  • RE: OP27 single supply issues in the use


    I have not been able to replicate what you have described below. Could I please clarify that the situation you are describing when pin 3 is grounded and pin 6 is 14V is the same as the schematic attached "OP27 schematic.jpg".

    One side…

  • Questions about PLL design with HMC698LP5


    My customer are designing PLL circuit  with HMC698LP5 (PLL), HMC391LP4(VCO) and OP27 (OPAMP).

    And the ouput frequency are 3.9GHz or 4.05Ghz and the reference frequency is 50MHz.

    Q1) when they implement a charge pump  of HMC698, can they implement…

  • OP07 Replacement

    Can I use OP27 instead of OP07 in my new application.

  • RE: OP27 Spice model


      I don't know of any spice models from any manufacturer that model temp co of Vos.

    Looking at the OP27 model, it appears it does include noise modeling.


  • RE: Noise reduction for negative reference

    The OP27 should drive that, but I would increase both, say 2.2k and put 10nF-100nF across RF.


  • RE: OP37


      The title is OP37, but your schematic shows OP27.  The pc board photo looks like an OP37.

    You are onlly running a noise gain 3-4 so you really need an OP27.  The OP37 should oscillate.

    If your board is not oscillating with an OP37, you got…