• HMC765 vs HMC767

    Hello there,

     We are thinking in migrating a current design from HMC767 to avoid excesively low tning voltages to get 8GHz output frequency. Our idea is to use HMC765 instead but phase noise floor degradation seems to be expected. My questions are:

    1.…

  • 关于hmc765的问题

    用hmc765LP6CE得到一个8GHz的信号,但是遇到了一些问题,具体如下:

         (1)根据datasheet上的调谐电压与输出频率的关系,输出8GHz的信号,只需要4V的电压,但是实际操作中发现,需要5.4V左右才能输出到8GHz的信号。

         (2)向寄存器里面写数,分别向Reg09、Reg02、Reg03寄存器写数,最后写入Reg03寄存器,有时候能够锁定,有时候不能锁定。电路参考芯片的参考电路图设计,检查无焊接问题。环路采用无源环路和正向放大的环路两种,均是有时候能锁定,有时候不能锁定。

  • Register programming sequence of the HMC765

    Dear dyoung1,

    Could you tell me what sequence do i program the registers of HMC765 and HMC820 (for example: with ADF4159: write reg R7,R6,R6,R5,R5,R4,R4,R3,R2,R1,R0)? Or Can i set registers with any sequence?

    And could you share with us  "recommended…

  • HMC765 Fractional PLL with integrated VCO

    Does this has built-in Flash Memory for registers, so that at power on it will wake up at the last programmed frequency.

    I wanted to use it as Fixed Frequency Oscillator, where Serial port programming is not feasible.

  • 关于HMC765寄存器配置问题

    谁能给一种整数分频的典型寄存器配置方案

    我现在不管寄存器配置成7.8G、8G还是8.8G,输出一直震荡在8.2G左右不受控制啊

    环路滤波器的带宽都设置成1M了,鉴相频率是10M,参考输入50M。

    目前的配置是这样的:

    4'd0:ctrl_word <= 32'b0_000000_0000_0000_0000_0000_0000_0001_0;//00h

    4'd1:ctrl_word <= 32'b0_000001_0000_0000_0000_0000_1000_0110_0;…

  • RE: Output is not getting locked in PLL hmc765 evaluation board

    Hi there,

    Not sure who Richard is...my name is Marty Relaxed

    I've attached the gerber files for the HMC765 evaluation board.For future reference, these files can sometimes be found be searching EZ or by visiting the Full Product Page for the model in question…

  • RE: What is the frequency of the ring oscilator for lock detect in the HMC765?

    We are using a 100 MHz reference and locking at a fixed frequency of 8 GHz with the HMC765.  You suggest: We recommend setting the lock window mid-way between the minimum (set by offset current) and the maximum (set by the reference period).

    We are in…

  • How to let HMC765LPCE to identify which register to write from SPI command?

    I would like to program the SPI (LE, Data and CLK) for the HMC765LPCE by using FPGA. I would like to achieve the output frequency of the PLL at 7912.5 MHz, is it correct to let R=1, Nint=158, and the Nfrac=2^22? How does HMC765 identify if I would like…

  • RE: PLL board layouts

    hmc764

    hmc765

    hmc783

    HMC807

    hmc767

    hmc769

    hmc778

    The HMC767, HMC769 and HMC778 share the same evaluation board. These can be found on the 'Discussion' section on the Full Product page for the HMC778 on the website (links back to EZ). I've attached…

  • RE: Gerber for Evaluation PCB of HMC820LP6CE and HMC765LP6CE

    I've attached the HMC820 and HMC765 gerber files.