ADF5610 EVB Ref Freq

Could anyone clarify and give me any advice?

Part : ADF5610

1. ADF5610 EVB Direct External Ref Freq connect
Using the ADF5610 EVB, I want to use Ref Freq=200MHz.
The ADF5610 EVB has HMC1031, so I know it is difficult to use.

So, External Ref Freq. I want to use it directly.
Is it the right way?

2. RF OUT at 12GHz
There is a VCO Register in the VCO Subsystem tap in ADF5610 EVB Software.
It is shown saturated at 12 GHz.
This is a PLL operating up to 14.6G.
Please tell me the right way to drive it.


Please kindly help.
Please. Can someone tell me?

Thanks in advance.

Top Replies

  • +1
    •  Analog Employees 
    on Mar 22, 2021 10:07 AM

    Hi,

    To address your questions: 

    So, External Ref Freq. I want to use it directly.
    Is it the right way?

    By default the eval board is set up for on-board reference. To reconfigure for external reference source, there are a number of discrete components to be removed/inserted. As documented in the eval board user guide (page 5):

    • Include 0 Ohms: R51, R47.
    • Remove: R33, C85, R100, R99, C50, C51, R52, C53.
    • Replace: L3 and C36 with a 0 Ω resistor. 
    • Set switch D0
    There is a VCO Register in the VCO Subsystem tap in ADF5610 EVB Software.
    It is shown saturated at 12 GHz.
    This is a PLL operating up to 14.6G.
    Please tell me the right way to drive it.

    When you say saturated, which value are you referring to? None of the values highlighted determine the frequency of operation. Auto-calibration is used to selected the operating frequency initially. This selects the VCO core and sub-band. This is outlined on p19 of the datasheet