AD9122 : Output power

Hello,

On my board, I have two AD9122 components.

I program the component with the below registers:

0x0D = 0xD6

0x0A = 0xF8

0x08 = 0xFF

0x1C = 0x04

0x1D = 0x24

0x1E = 0x12

All the others registers are the default value.

The ouput power is different on each AD9122 components. And if I use another baord, I have other ouput power.

Thanks for your help

Best Regards

Nicolas Delabie

Parents
  • Hi Biao Huang,

    You can find below my test process on AD9122 component. On my board, I have two AD9122 components.

    1/ AD9122 components are connected to Xilinx FPGA (xc5vsx95t).

    All the data pins are always level high.

    FRAMEP = ‘0’ and FRAMEN = ‘1’

    RESET = ‘1’

    DCIP and DCIN differential clock = 130MHz

    REFCLKP and REFCLKN differential clock = 130MHz

    DACCLKP and DACCLKN differential clock = 1040MHz

    2/ I program the registers with the below values

    0x0D = 0xD6
    0x0A = 0xF8
    0x08 = 0xFF
    0x1C = 0x04
    0x1D = 0x24
    0x1E = 0x12
    All the others registers have the default values.

    3/ I measure the frequency and the output power on IOUT1P output pin. The frequency is equal to 130MHz. However, the output power changes when I measure the signal on the others components or others boards.

    1st board – 1st AD9122 – Power = - 43 dBm

    1st board – 2nd AD9122 – Power = - 17 dBm

    2nd board – 1st AD9122 – Power = - 15 dBm

    2nd board – 2nd AD9122 – Power = - 8 dBm

    My question is why the output power changes strongly and it is not the same.

    Thanks for your support.

    Nicolas Delabie

Reply
  • Hi Biao Huang,

    You can find below my test process on AD9122 component. On my board, I have two AD9122 components.

    1/ AD9122 components are connected to Xilinx FPGA (xc5vsx95t).

    All the data pins are always level high.

    FRAMEP = ‘0’ and FRAMEN = ‘1’

    RESET = ‘1’

    DCIP and DCIN differential clock = 130MHz

    REFCLKP and REFCLKN differential clock = 130MHz

    DACCLKP and DACCLKN differential clock = 1040MHz

    2/ I program the registers with the below values

    0x0D = 0xD6
    0x0A = 0xF8
    0x08 = 0xFF
    0x1C = 0x04
    0x1D = 0x24
    0x1E = 0x12
    All the others registers have the default values.

    3/ I measure the frequency and the output power on IOUT1P output pin. The frequency is equal to 130MHz. However, the output power changes when I measure the signal on the others components or others boards.

    1st board – 1st AD9122 – Power = - 43 dBm

    1st board – 2nd AD9122 – Power = - 17 dBm

    2nd board – 1st AD9122 – Power = - 15 dBm

    2nd board – 2nd AD9122 – Power = - 8 dBm

    My question is why the output power changes strongly and it is not the same.

    Thanks for your support.

    Nicolas Delabie

Children
No Data