LMX2820EVM: Spectrum Noise peaks

chuckm

Part Number: LMX2820EVM

Are the noise peaks I am noticing due to the on-board regulators feeding the VCO?

I do have a wide bandwidth (~160kHz)

Changing the loop bw (narrower) did not seem to have any affect their level above the floor - not able to adjusting higher though.

Any suggestions?

Thank you

Best regards

Chuck

0 Noel Fung over 2 years ago

Hi Chuck,

The noises and peak are within loop bandwidth, they are coming from the input path or power supply.

Does the reference clock also have this issue?

In addition, your configuration is not correct. MULT has turned red, this is not a valid setting. You can mouse-over it to see the reasons.

0 chuckm over 2 years ago in reply to Noel Fung

Thank you Noel for your response. It was a lab power supply issue.

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