关于hmc1033 的问题,求帮忙,谢谢,弄了一个月了

自己做了hmc1033的PCB板,用来产生500MHZ的时钟信号,写寄存器的代码如下:

HMC1033_Write(0x0A,0x2006); //reg A
HMC1033_Write(0x08,0xC1BEfF);//reg8
HMC1033_Write(0x0F,0x81); //reg f
HMC1033_Write(0x07,0x14d); // reg7

HMC1033_Write(0x0B,0xF8061);//reg b
HMC1033_Write(0x0C,0x0); //reg c


HMC1033_Write(0x02,0x02); //XTAL R,Step1 reg 2
HMC1033_Write(0x06,0x2003CA);//A/B Mode,Step2 reg6
HMC1033_Write(0x09,0x10F264);//Charge Pump,Step3 reg 9

HMC1033_Write(0x05,0xFf88); // vco 01
HMC1033_Write(0x05,0xF98); // vco 3
HMC1033_Write(0x05,0x48B8); // vco 7
HMC1033_Write(0x05,0x0); //vco 0


HMC1033_Write(0x03,0x50); //reg 3
HMC1033_Write(0x04,0x0); //reg 4
HMC1033_Write(0x05,0x210); //VCO Subsystem,Step4 vco2

写完之后能产生500M的时钟,且信号质量也很好,但锁定指示引脚为低电平。重要的是,过几分钟后,产生的时钟就会严重抖动。结果如下图所示。我觉得hmc1033一直都没有锁定才产生此情况。

但也找不出什么问题,也不懂怎么解决,请问是我写寄存器顺序或是方法错误 吗?真心求帮忙,十分感谢

Parents
  • 0
    •  Analog Employees 
    on Jan 23, 2017 11:49 AM

    请参考下面evb的寄存器:hmc1033_fracfb_LVPECL_Low_Noise

    REVISION 1.0.1.0

    REG 0 A7975

    REG 1 2

    REG 2 1

    REG 3 2C

    REG 5 210

    REG 5 F98

    REG 5 4B38

    REG 5 0

    REG 6 200B4A

    REG 7 14D

    REG 8 C1BEFF

    REG 9 30ED5A

    REG A 2006

    REG B F8061

    REG C 0

    REG D 0

    REG E 0

    REG F 1

    REG 10 A2

    REG 11 19

    REG 12 3

    REG 13 1259

    REG 14 0

    REG 15 0

    REG 16 0

    REG 17 0

    REG 18 0

    REG 19 0

    REG 1A 0

    REG 1B 0

    REG 1C 0

    REG 1D 0

    REG 1E 0

    REG 1F 0

    REG 4 147AE1

    XTAL 50

    DIVIDER_MANUAL_MODE 0

    VCO_TO_SYNTH_DIV 1

    VCO_TO_OUT_DIV 4

Reply
  • 0
    •  Analog Employees 
    on Jan 23, 2017 11:49 AM

    请参考下面evb的寄存器:hmc1033_fracfb_LVPECL_Low_Noise

    REVISION 1.0.1.0

    REG 0 A7975

    REG 1 2

    REG 2 1

    REG 3 2C

    REG 5 210

    REG 5 F98

    REG 5 4B38

    REG 5 0

    REG 6 200B4A

    REG 7 14D

    REG 8 C1BEFF

    REG 9 30ED5A

    REG A 2006

    REG B F8061

    REG C 0

    REG D 0

    REG E 0

    REG F 1

    REG 10 A2

    REG 11 19

    REG 12 3

    REG 13 1259

    REG 14 0

    REG 15 0

    REG 16 0

    REG 17 0

    REG 18 0

    REG 19 0

    REG 1A 0

    REG 1B 0

    REG 1C 0

    REG 1D 0

    REG 1E 0

    REG 1F 0

    REG 4 147AE1

    XTAL 50

    DIVIDER_MANUAL_MODE 0

    VCO_TO_SYNTH_DIV 1

    VCO_TO_OUT_DIV 4

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