• HMC699 spurs


    I have a design based on the HMC699 PLL and HMC584 VCO with a CW output of 13.6GHz. Everything works just fine and the phase noise measurements match the simulation very good. However I have several high spurs close to the F0. The ref oscillator…

  • RE: HMC699 Programming Registers

    Hi Marty,

    I have news about this design, sorry for being offline too much time.

    Regarding the VCO we used you are right, we are working very close to the AD797 limits but we could not afford +15V power supply.

    The VCOs are working outside the datasheet…

  • RE: HMC699 Differential active loop filter help

    Hi Dan,

    We are starting a new design based on HMC699, we wonder if you could tell us the operational amplifier you used. We pretend to use the AD797 operational but its recommended power supplies are dual +-15 / +-5 (We have asked for some information…

  • Simulation models for HMC699 (PLL) with HMC583 (VCO)

    I need to design a 12-13 GHz low-noise frequency synthesizer based on the HMC699# PLL# and the HMC583# VCO#.

    Is it possible to have their models to simulate this system with Hittite's design tool v1.15 that I have downloaded from your site?

    By the…

  • Re: Simulation models for HMC699 (PLL) with HMC583 (VCO)

    Hi Huangzeyan,

    Thank you very much for your useful answer.

    I have still a couple of questions:

    1) Which is the best opamp you may suggest to keep the phase noise as low as possible?

    2) I am missing the reason why the phase detector gain is set to…

  • ADI SIM PLL - How to use the RFOUT/2 pin on an ADI VCO in a simulation?

    Hi all,

    I'm trying to recreate the PLL design that is in the HMC699 datasheet on page 11 (https://www.analog.com/media/en/technical-documentation/data-sheets/hmc699.pdf).

    First I would like to simulate it exactly in ADI SIM PLL.

    So far this is the…

  • RE: HMC3716 PFD in adiSimPLL

    Hi there,

    Please reference the EZ post below. The documents referred apply to all HMC PFD / INT PLL products including the HMC439, HMC440, HMC3716, HMC4069, HMC698 and HMC699.


    Best Regards,


  • RE: What is the phase noise of HMC439 at 10Hz offset for 10 MHz pdf?

    Hi Mustafa,

    The alternatives to the HMC440, which include LD, INV, and internal 200 ohm pull ups would be the HMC4069, HMC698, HMC699.  Each one has similar performance, just different divide ratios, so pick the one that suits your application.


  • RE: AD797 supply voltage limits

    Hi Harry, 

    I am designing a new PLL system based on HMC699 PLL which needs to use an active filter topology. From the ADISim PLL simulator I have used AD797 as operational amplifier and the simulations went ok with power supply from +12VDC to GND.


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