LMX2594: LMX2594EVM Phase noise simulation and EVM calculation issue

Waldner Wu

Part Number: LMX2594
Other Parts Discussed in Thread: PLLATINUMSIM-SW, ,

Hi Team:

I used PLLatinumSIM-SW to simulate LMX2594 phase noise at 6650MHz as following pic.

Then I try to calculate the EVM due to phase noise, it's -38.49dB.(Please see below pic)

I want to improve EVM from -38.49dB to -45dB.

Please help to tell me how can I do, thank you!!

Best regards,

Waldner

0 Vibhu Vanjari over 5 years ago

Hello Waldner,

I think there is some discrepancy between your loop filter components and the components on the EVM.

Your loop filter components in pllatinum sim do not match the components in the LMX2594EVM User's Guide:

Please refer to the schematic or "4 Loop Filter Configuration" section.

If you look in the filter designer section of the image you posted the actual loop filter is at around 100 kHz.

Thanks,

Vibhu

0 Waldner Wu over 5 years ago in reply to Vibhu Vanjari

Dear Vibhu:

Very thanks for your suggestion, I follow your suggest and use PLLatinum Sim tool to simulate and export excel data file.

I can get the "Error Vector Magnitude" from excel data file. It's very good(only 0.202%).

But I have one more question that the Error Vector Magnitude value is single side band EVM or double side band EVM?

Please help to tell me, thank you very much!!

Best regards,

Waldner

0 Noel Fung over 5 years ago in reply to Waldner Wu

Hi Waldner,

All the calculations are double side band.

0 Waldner Wu over 5 years ago in reply to Noel Fung

Dear Noel:

Thank you very much!!

Best regards,

Waldner

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