HMC544A: DC blocks at ports RFC, RF1 and RF2


I am working on a high speed data aquistion system. The low power RF signal of interest is DC coupled and therefore I was thinking of using the HMC544A as a switch. The datasheet looked promising (DC - 4GHz) until I have found the section that DC blocks are required. Using DC block capacitors is not an option. Would it be worth a try to leave out the DC blocks?

Thanks and best regards,


  • Hi

    HMC544 requires DC blocking capacitors at RF port when RF lines have DC voltage of 0 V.

    Can you provide me with the following information? I will check if you can use HMC544A without DC blocking capacitor in your application. 

    - DC voltage level of RF signal

    - Minimum frequency of operation

    - Maximum RF signal power


  • Hi,

    thanks for your help!

    I checked with my system and the following conditions will apply:

    - DC voltage level of RF signal                --> up to 1.5V

    - Minimum frequency of operation           --> Down to 0Hz

    - Maximum RF signal power                   --> Max. 17dBm

    I hope this will help you.

    Thanks in advance for your help!

    Best regards,


  • Hi,

    We have no RF switches including HMC544A that will handle DC bias of 1.5 V at the RF ports.


  • 0
    •  Analog Employees 
    on Aug 2, 2018 3:20 PM
    This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

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