hmc507

Hello, I want to use HMC507 in my design, but I have the following questions:
1) Is its output a sine wave? This is very important to me;
2) What I want is the RF OUT signal. I don’t need RFOUT/2 and RFOUT/4. How to remove them? As you mentioned in the previous answer, you need to install an appropriately sized capacitor for the frequency you're working with and a shunt 50 ohm resistor, how do you connect it and which port it is? Can you draw a schematic diagram?
3) Regarding pin 6 and pin 7, the description in the data sheet is inconsistent with the reference circuit, what should I do?
4) I see that the RFOUT port does not have a series capacitor, is it unnecessary?

best wishes!

  • 0
    •  Analog Employees 
    on Apr 21, 2021 11:21 AM

    Hi,

    To answer your questions: 

    1) Is its output a sine wave?

    - Yes it is a sinewave output

    2) What I want is the RF OUT signal. I don’t need RFOUT/2 and RFOUT/4. How to remove them?

    - You can terminate the RFOut/2 signal with a 50 ohm resistor to ground to ensure that they do not appear on the output signal. 

    3) Regarding pin 6 and pin 7, the description in the data sheet is inconsistent with the reference circuit, what should I do?

    - You can follow the datasheet guidelines. They wrong schematic appears to be uploaded for this. Thanks for highlighting this. 

    4) I see that the RFOUT port does not have a series capacitor, is it unnecessary?

    - If you are able to connect a DC block on the RF output coaxial connection, then it is not necessary to connect a series capacitor. 

  • Thank you very, very, very much for your reply. I am very happy to have your help.

    Your answer confirms that what I need is HMC507. But I still have some questions to ask, please allow me to describe it in detail.

    I need a 6.8GHz signal. The reference signal is 212.5MHz, which is exactly 32 times the frequency. I choose HMC440+HMC507 to complete this design. Generally speaking, the phase noise performance of discrete devices is better. This is why I do this. The reason for doing it. Questions are as follows:

    1)The Maximum VCO Input Frequency of HMC440 is 2800MHz, so the output of HMC507 needs to be divided by four. I originally planned to use HMC433 to complete this task, but when I was looking for a suitable operational amplifier for the loop filter designed for this, I found This one,

    After all, HMC507 also has RFOUT/4 port. If I refer to this design, do I need an extra divider?

    2)If I use HMC433, I can easily complete the loop filter design, like this

    But if I don't use an additional frequency divider, how to design in ADIsimPLL, like this?

    3) In addition, what voltage should I connect to the "VCC" I marked? I really don't understand.

    4) The HMC440 product introduction page recommends several operational amplifiers, including ADA4048-1, LT6200, and ADA4625-1. The latter two have models in ADIsimPLL. I prefer LT6200, and its noise performance looks better. , But it has many models, such as LT6200/LT6200-5,LT6200-10/LT6201,

    What is the principle of selection? This question can be combined with question 3);

    5) Last time I asked about PIN6 and PIN7 of HMC507, it looks like this in the data sheet

    This is the case in the PCB board and schematic diagram below.

    Is there any benefit to the latter?

    Thank you again for your reply and wish you and your family good health and all the best!

  • 0
    •  Analog Employees 
    on Apr 29, 2021 10:34 AM in reply to 任是潇洒也多情

    Hi,

    To address your questions: 

    1. 

    After all, HMC507 also has RFOUT/4 port. If I refer to this design, do I need an extra divider?

    - The HMC507 does not have a RFOUT/4 port and can not divide by 2. Refer to the chip pinout on the datasheet to confirm this. It is a little confusing because the eval board shows an RFOUT/4 port but this is because the eval board is used for multiple different devices of the same footprint and almost the same pin compatibility. 

    2. 

    But if I don't use an additional frequency divider, how to design in ADIsimPLL, like this?

    You would need to use an external frequency divider for this in SimPLL as there is no divide by 4. 

    3. 

    In addition, what voltage should I connect to the "VCC" I marked? I really don't understand.

    For the active loop filter you would need to connect +15v to VCC. This is because of the Vtune requirements of the VCO is between 0v to 13v. 

    4. 

    What is the principle of selection?

    There are several factors in op-amp selection which are performance related. As you can see in the LT6200 datasheet the difference between each of these models is the gain BW product. SimPLL has selected LT6200 as provided optimised performance. 

    5. 

    Is there any benefit to the latter?

    As mentioned in 1. above. The circuitry included on the eval board is not necessary for the HMC507. It is only used for other parts of the same footprint that use this board.

    Regards,

    Kieran