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LMH6553: EMIRR data requirement

Part Number: LMH6553

Hello there,

Is EMIRR data available for LMH6553, like the data curve shown below.

Customer met EMI issue with LMH6553, its output noise becomes larger due to RF interference, therefore, we need EMIRR data for analysis.

 

 

Best regards,

Shubiao Wang

  • Hello Shubiao,

    High speed amplifiers do not typically have EMI information in the datasheet.  Due to the high bandwidths of the amplifiers, the amplifiers usually pick up considerable RF during an EMI test.  For this reason, EMI testing is not typically performed for high speed products, including the LMH6553. 

    There is no EMIRR data available for the LMH6553.

    Best,

    Alec

  • Hello Alec,

    my LMH6553 output noise becomes worse @10Mhz. that is because the modulation signal is 10Mhz, Carrier wave is RF signal (2.4Ghz). the interference mainly comes from conduction interference @ input pins.

    my questions are:

    does it mean the LMH6553 act as a lower pass filter?

    how to avoid the 10Mhz output noise ?

    BRs,

    Shubiao

  • Hi Shubiao,

    where is the 2.4GHz coming from? Is it a regular signal, superimposed to your 10MHz? Then, low pass filtering in the signal chain could help.

    Or is it unwantedly injected into the signal chain by capacitive stray coupling? Then, shielding and the use of shielded cables (coax cables) can help.

    Eventually, the unwanted 2.4GHz is common mode intereference and can be suppressed by a suited clamp-on ferrite on a coax cable? In this case you would not need to change anything in the signal chain.

    Kai

  • Hello Shubiao,

    I also would like additional details regarding your setup and the RF signal.  Without knowing more about the circuit, connectors, and overall setup, it is difficult to provide a recommendation or idea.  

    Best,

    Alec